NORD BU0050 User Manual

SK TU1-DEV
SK TU2-DEV
SK TU3-DEV

GB

BU 0050

USS Bus modules and MODBUS RTU

Supplementary manual for NORD frequency inverters

NORD USS and Modbus RTU Manual Safety information

N O R D Frequency inverters

Safety and operating instructions for

drive power converters

(as per: Low Voltage Directive 2006/95/EEC )

1. General
During operation, drive power converters may, depending on their

protection class, have live, bare, moving or rotating parts or hot
surfaces.

Unauthorised removal of covers, improper use, incorrect installation
or operation causes a risk of serious personal injury or material
damage.

Further information can be found in this documentation.
All transportation, installation, initialisation and maintenance work

must be carried out by qualified personnel (compliant with
IEC 364, CENELEC HD 384, DIN VDE 0100, IEC 664 or
DIN VDE 0110, and national accident prevention regulations).

For the purposes of these basic safety instructions, qualified
personnel are persons who are familiar with the assembly,
installation, commissioning and operation of this product and who
have the relevant qualifications for their work.

2. Proper use in Europe

Drive power converters are components intended for installation in
electrical systems or machines.

When installed in machines, the drive power converter cannot be
commissioned (i.e. commencement of the proper use) until it has
been ensured that the machine meets the provisions of the EC
Directive 2006/42/EEC (Machine Directive); EN 60204 must also be
complied with.

Commissioning (i.e. implementation of the proper use) is only
permitted if the EMC Directive (2004/108/EEC) is complied with.

Drive power converters with the CE mark meet the requirements of
the Low Voltage Directive 2006/95/EEC. The harmonized standards
stated in the Declaration of Conformity are used for the drive power
converters.

Technical data and information for connection conditions can be
found on the name plate and in the documentation, and must be
complied with.

The drive power converters may only be used for the safety
functions which are described and for which they have been
explicitly approved.

3. Transport, storage

Information regarding transport, storage and correct handling must
be complied with.

4. Installation

The installation and cooling of the equipment must be implemented
according to the regulations in the corresponding documentation.

The drive power converters must be protected against
impermissible loads. Especially during transport and
handling, components must not be deformed and/or
insulation distances must not be changed. Touching of
electronic components and contacts must be avoided.

Drive power converters have electrostatically sensitive
components, which can be easily damaged by incorrect
handling. Electrical components must not be mechanically
damaged or destroyed (this may cause a health hazard!).

5. Electrical connections

When working on live drive power converters, the applicable
national accident prevention regulations must be complied
with (e.g. VBG A3, formerly VBG 4).

The electrical installation must be implemented according to
the applicable regulations (e.g. cable cross-section, fuses,
ground lead connections). Further information is contained
in the documentation.

Information about EMC-compliant installation – such as
shielding, earthing, location of filters and installation of
cables can be found in the drive power converter
documentation. These instructions must be complied with
even with CE marked drive power converters. Compliance
with the limiting values specified in the EMC regulations is
the responsibility of the manufacturer of the system or
machine.

6. Operation

Where necessary, systems where drive power converters
are installed must be equipped with additional monitoring
and protective equipment according to the applicable safety
requirements, e.g. legislation concerning technical
equipment, accident prevention regulations, etc.

The parameterisation and configuration of the drive power
converter must be selected so that no hazards can occur.

All covers must be kept closed during operation.

7. Maintenance and repairs

After the drive power converter is disconnected from the
power supply, live equipment components and power
connections should not be touched immediately, because of
possible charged capacitors. Observe the relevant
information signs located on the drive power converter.

Further information can be found in this documentation.

These safety instructions must be kept in a safe place!

2 Subject to technical amendments BU 0050 GB-3111

NORD USS and Modbus RTU Manual Concerning this document

Designation of
previous issues

Software
Version

Comments

BU 0500 GB, December 2004
Part No. 607 0502 / 5204

Latest version

BU 0050 GB, August 2011
Part No. 607 0502 / 3111

 Deletion of option "DevicenNet mc" for FI series

"vector mc"

 Inclusion of SK 500E series frequency inverters
 Implementation of Modbus RTU (for SK 500E)

NOTE

This supplementary operating manual is only valid in conjunction with the operating manual
supplied for the respective frequency inverter.

Documentation

Designation: BU 0050 GB
Part No.: 607 05 01
Device series: USS for SK 300E, SK 500E (entire series), SK 700E, SK 750E
Modbus RTU for SK 540E and SK 545E

Version list

Publisher

Getriebebau NORD GmbH & Co. KG

Rudolf-Diesel-Str. 1  D-22941 Bargteheide  http://www.nord.com/
Tel.: [phone] / 401-0  Fax [phone] / 401-555

BU 0050 GB-3111 Subject to technical amendments 3

NORD DeviceNet Manual Concerning this document

Intended use of the frequency inverter

Compliance with the operating instructions is necessary for fault-free operation and the

acceptance of any warranty claims. These operating instructions must be read before
working with the device!

These operating instructions contain important information about servicing. They must
therefore be kept close to the device.

The described optional modules can only be used for the specifically defined frequency
inverter series, use across series is only possible with the SK TU2-… module with SK 300E
and SK 750E. The use of these modules with other devices is not permitted and can lead to
their destruction.

The described optional modules and the corresponding frequency inverters are devices for
stationary installation in control cabinets or decentralised structures. All details
regarding technical data and permissible conditions at the installation site must be
complied with.

Commissioning (commencement of the intended use) is not permitted until it has been ensured
that the machine complies with the EMC Directive 204/108/EEC and that the conformity of
the end product meets the Machinery Directive 2006/42/EEC (observe EN 60204).

 Getriebebau NORD GmbH & Co. KG, 2011

4 Subject to technical amendments BU 0050 GB-3111

Contents

FOREWORD ................................................................................................................................ 7

1 USS ........................................................................................................................................... 7

1.1 General information .............................................................................................. 7

1.1.1 The USS Protocol ..................................................................................................... 7

1.1.2 Features .................................................................................................................... 7

1.1.3 Delivery ..................................................................................................................... 7

1.1.4 Scope of supply ......................................................................................................... 8

1.1.5 Certifications ............................................................................................................. 8

1.1.6 Identification System ................................................................................................. 8

1.2 Modules ................................................................................................................ 9

1.2.1 SK 500E .................................................................................................................... 9

1.2.2 SK 700E .................................................................................................................. 12

1.2.3 SK 300E .................................................................................................................. 18

1.3 USS Protocol Specification ................................................................................ 19

1.3.1 General information................................................................................................. 19

1.3.2 Telegram Structure ................................................................................................. 19

1.3.3 Data Coding ............................................................................................................ 20

1.3.4 Character Frame ..................................................................................................... 20

1.3.5 Transfer Procedure ................................................................................................. 21

1.3.6 Start Pause Time .................................................................................................... 21

1.3.7 Response Delay Time ............................................................................................. 22

1.4 Bus Configuration ............................................................................................... 23

1.4.1 General information................................................................................................. 23

1.4.2 Topology ................................................................................................................. 23

1.4.3 Transfer Method ...................................................................................................... 23

1.4.4 Installation of the Bus System ................................................................................. 24

1.5 Data transmission ............................................................................................... 26

1.5.1 Structure of reference data ..................................................................................... 26

1.5.2 PPO types ................................................................................................ ............... 27

1.5.3 Process data (PZD)................................................................................................. 29

1.5.4 Parameter range (PKW) .......................................................................................... 39

1.6 Telegram examples ............................................................................................ 43

1.6.1 The Macro Generator .............................................................................................. 43

1.6.2 Switch-on block  Standby .................................................................................... 44

1.6.3 Enable with 50% setpoint ........................................................................................ 46

1.6.4 Writing a parameter................................................................................................. 47

1.6.5 Reading the acceleration time parameter ............................................................... 48

1.7 Master Telegram Times ..................................................................................... 49

1.8 Frequency Inverter Settings ............................................................................... 50

1.8.1 Frequency inverter bus parameters ........................................................................ 50

2 MODBUS RTU ........................................................................................................................ 61

2.1 The bus system .................................................................................................. 61

2.2 Features ............................................................................................................. 61

2.3 Telegram Structure ............................................................................................. 62

2.4 RTU Frames ....................................................................................................... 62

2.5 Function Codes .................................................................................................. 62

2.5.1 01h Read Coil ......................................................................................................... 63

2.5.2 05h Write Single Coils ............................................................................................. 63

2.5.3 0Fh Write Multiple Coils .......................................................................................... 64

2.5.4 03h Read Holding Register ..................................................................................... 65

2.5.5 06h Write Single Register ....................................................................................... 66

2.5.6 10h Write Multiple Register ..................................................................................... 66

2.6 Exception Responses ......................................................................................... 68

2.7 Watchdog ........................................................................................................... 68

2.8 Description of parameters .................................................................................. 69

BU 0050 GB-3111 Subject to technical amendments 5

NORD USS and Modbus RTU Manual

3 FAULTS .................................................................................................................................. 71

3.1 Troubleshooting ................................................................................................. 71

3.1.1 Error display............................................................................................................ 71

3.1.2 Error memory .......................................................................................................... 71

3.2 Error messages ................................................................................................. 72

4 ADDITIONAL INFORMATION ............................................................................................... 73

4.1 Maintenance and servicing information ............................................................. 73

4.2 Abbreviations in this manual .............................................................................. 73

5 KEYWORD INDEX ................................................................................................................. 74

6 Subject to technical amendments BU 0050 GB-3111

1.1 USS - General information

Foreword

This supplementary documentation is valid for the SK 300E, SK 500E, SK 700E series and for the SK 750E.
It describes the setup of communication via RS485.

For this, the main emphasis is on communication according to the USS protocol. Corresponding optional
modules are available for the SK 700E and SK 750E series. The SK 300E and SK 500E series have an
appropriate interface integrated as standard.

In addition, the requirements of Modbus communication (SK 540E and higher) will be considered.

1 USS

1.1 General information

1.1.1 The USS Protocol

With the aid of the USS protocol, a user can set up a serial bus coupling between a higher level Master and
several slave systems. Master systems can for example be memory programmable control units (SPS) or
PCs.

The USS protocol allows the user to implement automation tasks with conveying according to time-cycled
telegram traffic (fixed telegram length required), as well as visualisation tasks.

The USS protocol is a simple, serial transfer protocol defined by Siemens, which if fully tailored to the needs
of drive technology.

1.1.2 Features

Support of a multiple point coupling, e.g. EIA RS 485 hardware or a point-to-point coupling, e.g. EIA RS 232.

 Master / Slave access procedure
 Single Master System
 Maximum 32 participants (maximum 31 slaves)
 Simple, secure telegram framework
 Same physical bus design as PROFIBUS (DIN 19245 Part 1)
 The data interface to the basic device is according to the PROFILE for variable speed drives.

This means that with USS, the information to the drive unit is transferred in the same way as with the
PROFIBUS-DP.

 Can be used for commissioning, service and automation
 Service tools on PC (NORD CON)
 Simple to implement in customer-specific systems-

1.1.3 Delivery

Check the equipment immediately after delivery/unpacking for transport damage such as deformation or
loose parts.

If there is any damage, contact the carrier immediately and carry out a thorough assessment.

Important! This also applies even if the packaging is undamaged.

BU 0050 GB-3111 Subject to technical amendments 7

NORD USS and Modbus RTU Manual

SK TU1-RS2

Bus system: AS1 = AS-Interface, CAN = CAN, CAO = CANopen,
RS2 = RS232, USS = USS, etc.
Device series: SK TU1 / SK TU2 / SK TU3

1.1.4 Scope of supply

SK TU1-RS232* for frequency inverter SK 700E IP20 or
SK CU1-STD for frequency inverter SK 700E, SK 750E IP20 or
SK CU1-USS for frequency inverter SK 700E, SK 750E IP20 or

*incl. screw for optional fixing to the FI

1.1.5 Certifications

1.1.5.1 European EMC Directive

If NORD frequency inverters or their options are installed according to the
recommendations in this instruction manual, it meets all EMC directive
requirements, as per the EMC product standard for motor-operated systems
EN 61800-3.

1.1.5.2 RoHS compliance

The bus options described here are designed to be RoHS compliant
according to Directive 2002/95/EEC

1.1.6 Identification System

8 Subject to technical amendments BU 0050 GB-3111

1.2 USS - Modules

WARNING

NOTE

Modules should not be inserted or removed unless the device is free of voltage. The slots may
only be used for the intended modules.

Installation of a technology unit separate from the frequency inverter is not possible. It must be
connected directly to the frequency inverter.

LED

red/green

1.2 Modules

1.2.1 SK 500E

1.2.1.1 General

By the use of various modules for display, control and parameterisation, the SK 5xxE can be easily adapted
to various requirements.

Alphanumerical display and operating modules can be used for simple commissioning. For more complex
tasks, various connections to a PC or an automation system can be selected.

The technology unit (Technology Unit, SK TU3-…) is connected externally to the frequency inverter and is
therefore easy to access and replace at any time.

As delivered, without the technology unit, 2 LEDs (green/red) are visible externally. These indicate the actual
device status.

The green LED indicates that the mains voltage is present and operational, while a flashing code that
increases in speed shows the degree of overload at the frequency inverter output.

The red LED signals actual error by flashing with a frequency which corresponds to the number code of the
error (Manual BU 0500 Section 6).

BU 0050 GB-3111 Subject to technical amendments 9

NORD USS and Modbus RTU Manual

X7: additional terminal

block with RS485
interface
(terminals 73/74)

SK 520Eor higher

X11: 1x RJ12 socket to

connect the RS232
or RS485 interface

X11

1.2.1.2 RS 485 interface

As standard, all devices in the SK 500E series have an integrated interface for USS bus communication.
According the version of the Fi, the following interfces are available:
X11 RJ12 socket (available for the entire series)
X7:73/74 RS485 + / - terminal connection (available for SK 520E or higher)

10 Subject to technical amendments BU 0050 GB-3111

1.2 USS - Modules

Contact

Function

Data

Description / wiring suggestion

DIP switch 1/2 (top side of frequency inverter)

DIP-1

Termination resistor for RS485 interface
(RJ12); ON = switched in
[Default = "OFF"]
For RS232 communication DIP1 to "OFF"

X11 X10 X9

RS4 85 _ A

RS4 85 _B

G N D

TXD

RXD

+ 5V

1 2

ON

CAN _H

CAN _L

CAN _GN DncCAN _SHLD

CAN _GN DncCAN _24 V

CAN _H

CAN _L

CAN _GN DncCAN _SHLD

CAN _GN DncCAN _24 V

RS48 5_A

RS48 5_B

GN D

TXD

RXD

+ 5 V

SK 511E and above

RS232/485 DIP CAN/CANopen

DIP-2
Termination resistor for CAN/CANopen

interface (RJ12); ON = switched in
[Default = "OFF"]

Terminal

Function

Data

Description / wiring suggestion

X7:73

Data cable RS485

Baud rate
9600…38400Baud

Termination resistor
R=120

BUS connection parallel to RS485 on RJ12 plug
NOTE: The termination resistance of DIP switch 1 (see

RJ12/RJ45) can also be used for contacts 73/74.

X7:74

NOTE

To ensure reliable communication, a termination resistor (DIP switch DIP1) must be set at both
ends of the bus.

RJ 12 socket (X11)
In addition to the RS485 interface, the RJ12 socket also provides an interface for communication via RS 232.

However, the RS232 interface is only intended for connecting a PC.
If a network is to be set up with several participants which communicate via USS (frequency inverters), it

must be noted that communication must be via RS 485.
The RS232 interface (contacts X11:TXD and X11:RXD) cannot be deactivated on the frequency inverter. In

order to prevent a short circuit of these data cables and therefore the destruction of the RS232 driver, the
contacts TXD, RXD and +5V must not have a common connection to several frequency inverters.

Terminal connection (X7:73/74)
Above configuration level SK520E the frequency inverters are equipped with an additional terminal block

(X7). This provides the possibility of setting up the RS485 bus communication via contacts 73 and 74.

BU 0050 GB-3111 Subject to technical amendments 11

NORD USS and Modbus RTU Manual

Technology units (Technology Units) are modules which can be inserted
from above for display, parameterisation and control of the inverter.

WARNING

NOTE

Modules must not be inserted or removed unless the device is free of voltage. The slots may

only be used for the intended modules. The slots are coded to prevent them from being
incorrectly connected.

Installation of a technology unit separate from the frequency inverter is not possible. It must be

connected directly to the frequency inverter.

Customer interfaces (Customer Units) are modules which are
inserted into the upper slot inside the inverter. They are used for
control and communication using digital/analog signals or bus
interfaces.

Special extensions (EXtension Units) are inserted into the lower slot of
the inverter. Such an extension unit is required if the speed is to be
controlled or positioning is to be carried out by an incremental (absolute)
encoder.

1.2.2 SK 700E

1.2.2.1 General

With the combination of modules for display, technology units and modules with digital and analog inputs
and interfaces, customer interfaces or special extensions, the SK 700E can be easily extended to cater
for the requirements of a wide range of applications.

12 Subject to technical amendments BU 0050 GB-3111

WARNING

NOTE

Modules must not be inserted or removed unless the device is free of voltage. The slots may
only be used for the intended modules.

Installation of a technology unit separate from the frequency inverter is not possible. It must be
connected directly to the frequency inverter.

RXD

0V

TXD

6 1 5

9

5V

700E

N O RD A C

700E

N O RD A C

1.2.2.2 Technology Box RS232

(SK TU1-RS2, Option)

The Technology Box (Technology Unit) is clipped to the outside of the inverter.
The RS232 interface enables simple connection of an SK 700E to a PC with a

serial interface.
Communication between PC and frequency inverter can be set up using the

NORD CON Software (Windows). This is used for the control, parameterisation
and display of operating values of the frequency inverter.

This allows a simple functional test of the inverter to be carried out and,
following successful parameterisation, the data set can be saved as a file.

1.2.2.3 Installation of the SK TU1 technology unit

1.2 USS - Modules

Installation of the technology units must be carried out as follows:

1. Switch off the mains voltage, observe the waiting period.

2. Remove the dummy cover by actuating the unlocking device on the top and bottom edge.

3. Allow the technology unit to engage audibly by pressing lightly on the mounting surface.

BU 0050 GB-3111 Subject to technical amendments 13

NORD USS and Modbus RTU Manual

Connector

Functions

Maximum cross-section

Parameter

X1.1

Output relay

1,5 mm2

P434 ... P443

X1.2

Analog signals IN / OUT

1,0 mm2

P400 ... P419

X1.3

Digital inputs

1,0 mm2

P420 ... P423

X1.4

Bus signals / power supply

1,0 mm2

P503 ... P548

74 RS485 -

X1.1

X1.2

X1.3

X1.4

11 VREF 10V
12 AGND /0V
13 AIN1 ­14 AIN1 +
17 AOUT1

21 DIG IN 1
22 DIG IN 2
23 DIG IN 3
24 DIG IN 4
42 VO +15V

41 VO +5V
40 GND /0V
73 RS485 +

01 REL1.1
02 REL1.2
03 REL2.1
04 REL2.2

NOTE: All control voltages are based on a common reference potential!

Potentials AGND /0V and GND /0V are internally linked in the device.

The maximum total current 5/15V is 300mA!

Potentialfreier Kontakt oder
Ausgang einer SPS: 7,5...33V

(low = 0...3,5Volt)

Differenzeingang 0...10V

0...20mA

Voltage supply: 5V
RS 485 (USS protocol)

5V supply for ParameterBox,
p-box or motor thermistor

Data cables USS protocol

Digitale Eingänge:
DIG IN 1 = Ein rechts
DIG IN 2 = Ein links
DIG IN 3 = Parametersatz bit 0
DIG IN 4 = Festfrequenz 1

Ausgangsrelais:
max. 2,0A
28V DC /230V AC

U

REF

= 10V / I

max

= 10 mA

Analogausgang SPS: 0...10V
oder Potentiometer: 2...10k

Spannungsversorgung: 15V

Termination resistor for
RS 485 interface (120)

Zuschaltbarer Bürdenwiderstand für
0/4...20mA Analogeingang (250)

U/I switching

Analog input,

250

ON = Current,

OFF = Voltage

Termination

resistor

RS 485

120

O
F
F

O
F
F

1.2.2.4 Customer unit Standard I/O

(SK CU1-STD, Option)

The standard I/O of the customer interface(Customer Unit) provides
sufficient control terminals for most applications and it is fully
terminal-compatible with NORDAC vector mc..

1 analog differential input, 4 digital inputs and 1 analog output are
available for control of the frequency inverter.

Readiness for operation is shown via the 2 relay contacts and a
mechanical motor brake is activated at the correct time.

The connected frequency inverter can be accessed via the RS485
interface. In addition to the entire range of control functions,
parameterisation is also possible.

TheNORD CON software can be used to carry out a simple function
test of the serial interface and the parameterisation of the inverter.
For this, an interface converter (e.g. SK IC1-232/485) must be used
between the PC and the inverter. Following successful
parameterisation, the complete data set can be stored as a file by
means of NORD CON.

14 Subject to technical amendments BU 0050 GB-3111

1.2 USS - Modules

Connector

Functions

Maximum cross-section

Parameter

X4.1

Output relay

1,5 mm2

P434 ... P436

X4.2

Digital input

1,5 mm2

P420

X4.3

Data cables

1,5 mm2

P503 ... P548

NOTE: All control voltages are based on a common reference potential!

Potentials AGND /0V and GND /0V are internally linked in the device.

The maximum total current 5/15V is 300mA!

X4.1

X4.2

X4.3

01 REL1.1
02 REL1.2

41 VO +5V
40 GND /0V
73 RS485+
74 RS485-

21 DIG IN 1

42 VO +15V

Data cables:
RS485

(terminal 73-74, RS485 +/-)

Control signal: 2.5 ... 33V

Output relay:
Max. 2.0A
28V DC /230 V AC

Digital input 1 (P420)

Voltage supply: 15V

USS

USS termination resistor

not connected

connected

ON

1.2.2.5 USS Customer Interface

(SK CU1-USS, Option)

In addition to data connections, the USS customer units are also
equipped with conventional digital inputs and outputs.

Via the existing relay contacts, a mechanical motor brake can be
controlled or readiness for operation can be communicated to a
higher level system.

The digital input has a 2.5V switching threshold for the evaluation
of the temperature sensor. The input can, however, also be used
for an emergency stop function.

BU 0050 GB-3111 Subject to technical amendments 15

NORD USS and Modbus RTU Manual

WARNING

NOTE

Installation must be carried out by qualified personnel only, paying particular
attention to safety and warning instructions.

A customer interface must not be replaced while it is carrying voltage.

Kundenschnittstelle

Sondererweiterung

Technologiebox

Verrieglungsstift

CLOSED

OPEN

Verriegelung geschlossen
Verriegelung geöffnet

Locking pin

Technology unit

Customer interface

Special extension
unit

Locking device closed

Locking device open

1.2.2.6 Installation of customer units

1. Switch off the mains voltage, observe
the waiting period.

2. Remove the cover grid from the
connection area by loosening the 2
screws and levering out the device cover
(slot) or simply pull it out.

3. Locking lever in the "open" position.

4. Using light pressure push the customer
unit into the upper guide rail until it
engages.

5. Move the locking lever to the "closed"
position.

6. Remove the connector by pressing the
releases then make the necessary
connections. Then insert the connectors
until they engage.

7. Replace all covers.

16 Subject to technical amendments BU 0050 GB-3111

1.2 USS - Modules

Motor
PTC

Supply voltage
+5V

Digital
input

Removing customer units:

1. Switch off the mains voltage, observe the waiting period.

2. Remove the cover grid from the connection area by loosening the 2 screws and levering out the device
cover (slot) or simply pull it out.

3. Locking lever in the "open" position.

4. Using a screwdriver (as shown), lever the customer unit out of its engaged position and then remove it by
hand.

5. Move the locking lever to the "closed" position.

6. Replace all covers.

Motor temperature protection applies for all customer units!

For secure protection against motor overheating, a
temperature sensor (thermistor, PTC) can be connected
to any digital input.

The appropriate parameters (P420 ... P425, depending on
option) must be set to a value of 13 (PTC thermistor input)
for this purpose.

The supply voltage varies dependent upon the customer
unit. The lowest voltage possible should be chosen.

Internal switching in the inverter prevents excessive PTC
voltage.

The cable routing should always be separate from the motor cable and with shielded cables.

BU 0050 GB-3111 Subject to technical amendments 17

NORD USS and Modbus RTU Manual

M12 connector (Detail 1)

Terminal (Detail 2)

Functions

Maximum cross-section

4 (black)

73

RS485 +

1,5 mm2

3 (blue)

74

RS485 -

1,5 mm2

2 (white)

41

+5V

1,5 mm

2

1 (brown)

40

0V, GND

1,5 mm2

3,0 m

1

2

1.2.3 SK 300E

Technology units and customer interfaces

Through the combination of modules for the
display, (technology units) and modules with
digital and analog inputs, as well as interfaces,
(customer units) or bus interfaces, the SK 300E
can be easily adapted to the requirements of a
wide range of applications.

The NORD CON software can be used to carry
out a simple function test of the serial interface
and parameterisation of the inverter. For this, an
interface converter (e.g. SK IC1-232/485) must
be used between the PC and the inverter.
Following successful parameterisation, the
complete data set can be stored as a file by
means of NORD CON.

Further details can be found in Manual BU 0300.

USS interface (RS485)

With the SK 300E, an RS485 interface is lead out to a 4-pin M12
round connector (Detail 1) as standard. In addition to being used
for external control (ParameterBox) it can also be used as a bus
interface.

If required an M12  SUB D9 (Part No.. 278910060) connecting
cable is available.

Parallel to the external M12 connection, in the connection unit
(trio interface, removed from FI) terminals 73/74 are also
available for connection.

The RS485 termination resistor (Detail 2) can be switched in or
out using the DIP switch in the connection unit.

18 Subject to technical amendments BU 0050 GB-3111

1.3 USS - Protocol speciication

STX

LGE

ADR

N1

N2

..

Nn

BCC

1.3 USS Protocol Specification

1.3.1 General information

The USS protocol defines an access procedure according to the Master/Slave principle for communication
via a serial bus. A sub-set of this also includes point-to-point connection. A master and a maximum of 31
slaves can be connected to a bus. The individual slaves are accessed by the master via an address
character in the telegram. Direct exchange of messages between the individual slaves is not possible.
Communication is carried out in semi-duplex mode. The master function cannot be transferred (single master
system).

Data transfer via the two-cable bus is carried out by individual characters in the format:
1 start bit, 8 data bits 1 even parity bit and 1 stop bit (8E1) - This results in a character frame of 11 bits.

The direction of the data on the bus (transmit or receive) is specified by the master.

1.3.2 Telegram Structure

Each telegram starts with the start character STX (= 02 Hex), followed by the length (LGE) and the address
byte (ADR). This is followed by the information characters. The telegram

is concluded by the data saving character BCC (Block Check Character).

For word information (16 Bit) in the information data block (= information character block) the High Byte (first
character) is always transmitted first, followed by the Low Byte (second character). The same applies for
double-word information:

First the High Word is transmitted, followed by the Low Word.

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STX

(Start of Text): ASCII character: 02 Hex
The start character forms the first character in the telegram and together with the start pause it is used

for reliable detection of the start of the telegram.

LGE

(Telegram length): 1 Byte, contains the length of the telegram.
The telegram length is located in the 2nd byte of the telegram and indicates the length of the telegram

from the 3rd byte onwards. Specification of the length enables differentiation between the various types
of telegram. The data recipient can use the length byte to check the number of characters to be
received.

ADR

(Address byte): 1 byte, also contains the slave address.

Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

0 M BC | Address (0..30) |

The USS address is located in the 3rd byte (data bits 0 to 4) of the telegram. The slave device which is
to transmit or receive data is identified via the USS address. Therefore, a maximum of one slave device
can be represented by each of the 31 possible addresses For this, the appropriate address must be set
in the slave device. Bit 5 and Bit 6 have a special meaning.

Bit 5 Broadcast: A so-called broadcast telegram can be triggered by setting this bit. In a broadcast
telegram, address bits 0 to 4 are ignored by the connected slaves, i.e. the transmitted telegram is
processed by all of the slaves. However, in contrast to standard addressing, the slaves do not transmit a
response telegram as this would result in bus conflicts.

Bit 6 Echo: By setting the 6th bit, the inverter returns a telegram which is identical to the one which it
has received (for commissioning).

N1... Nn

Information characters: each one byte, content depending on task

BCC

1 byte, data saving character (Block Check Character)
The check-sum BCC is formed byte-wise over the entire telegram as an Exclusive OR link. The result

after the last net character is then the BCC.

BCC = STX XOR LGE XOR ADR XOR N1 XOR....N

N

1.3.3 Data Coding

1.3.4 Character Frame

Each transmitted character begins with a start bit (logical 0) and end with a stop bit (logical 1). 8 bits (1 byte)
are transmitted. Saving is performed by a parity bit (even parity). Therefore 11 bits are transmitted for each
character.

20 Subject to technical amendments BU 0050 GB-3111

1.3 USS - Protocol speciication

Time

Size

Meaning

t

SP

Minimum 2 character durations*

Start pause time

t

AVZ

Maximum 20 ms

Response Delay Time

t

TLZ

1.5 x consecutive telegram duration

= 1,5 x (n+4) x character duration

Max. residual telegram duration

t

ZVZ

Smallest start pause time

Character delay time

*Character duration = 11 x (1/Baud rate)

Master

BCC

LGE

ADR

1. n BCC

STX

STX

LGE

ADR

1. n BCC

t

SP

t

AVZ

STX

t

SP

t

TLZ

Slave

x

x+1

t

ZVZ

1.3.5 Transfer Procedure

The USS protocol functions according to the master/slave principle, whereby the master is the control device
(PC, SPS etc) and the slaves are the frequency inverters

Only one slave can be addressed with each telegram (exception: broadcast telegram without response by
the slaves).

In order to ensure reliable detection of the start of the telegram by the slave, the master must observe a so­called start pause between the receipt of the slave telegram and transmission of the next telegram. The
master starts to transmit a telegram. After the data package has been sent, the master switches the bus data
direction from transmission to reception. The slave addressed in the telegram must respond within a
specified response time.

The lengths of the master and slave telegrams are the same, i.e. the master telegram determines the length
of the response by the slave.

Telegram traffic can be cyclical a acyclical.

The following time definitions must be observed:

1.3.6 Start Pause Time

The start character STX (= 02 Hex) on its own is not sufficient to enable the slaves to uniquely identify the
start of a telegram, because the bit combination 02/Hex may also occur in the information characters.
Therefore, in advance of the STX a start pause time tSP where no characters are sent for at least the
duration of 2 characters is specified for the master. The start pause time is a component of the order
telegram. A valid telegram is only identified by an STX with a preceding start pause.

The exchange of data is always performed according to the pattern described above (semi-duplex
operation):

The minimum start pause time which is to be observed for the various baud rates can be found in the Master
Telegram Time table in the Additional Information section.

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1.3.7 Response Delay Time

The time interval between the last character of the order telegram (BCC) and the start of the response
telegram (STX) is called the response delay time t
20ms, however, it must not be smaller than the start pause. If the addressed participant does not
respond within the maximum permissible response delay time, an error message is saved in the master. The
master then sends the telegram which is intended for the next slave.

The minimum response delay time which is to be observed for the various baud rates can be found in the
Master Telegram Time table in the Additional Information section.

. The maximum permissible response delay time is

AVZ

22 Subject to technical amendments BU 0050 GB-3111

1.4 USS - Bus structure

1.4 Bus Configuration

1.4.1 General information

The basis for the physical interface of the USS protocol is the 'Recommended Standard RS-485'
For point-to-point connections, a sub-set of EIA RS-232 (CCITT V.24), TTY (20mA current loop) or optic fibre

cable can be used as the physical interface.
SK 300E and SK 500E series inverters are always configured with an RS485 interface on the terminal

connection bar or connector. For SK 700E series devices, the customer interface standard or USS must be
selected.

For the SK 700E series, RS 232 technology modules can be used for communication (only point-to-point
communication possible)

1.4.2 Topology

The USS bus is based on a linear topology without spur cables. Both ends of the lines end at a participant and
must be terminated there with bus termination networks.

The maximum cable length and the maximum distance between the master and the last slave is restricted by
the properties of the cable, the ambient conditions and the transfer rate. With a transfer rate < 100kbit/s, a
maximum length of 1200m is possible.

[EIA Standard RS-422-A December 1978, Appendix, Page 14]
The number of participants is restricted to 32 (1 master, 31 slaves).

1.4.3 Transfer Method

Transfer is by the half-duplex method, i.e. alternation between transmission and reception, and must be
controlled by the software. The half-duplex method allows the use of the same cables for both transfer
directions.

This enables simple and low-cost bus wiring, operation in environments where there is interference as well as
a high data transfer rate.

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1.4.4 Installation of the Bus System

In an industrial environment the correct installation of the bus system is particularly important in order to
reduce potential interference. The following points are designed to help prevent interference and problems
right from the start.

The installation guidelines are not complete and applicable safety and accident prevention guidelines must be
complied with.

1.4.4.1 Cable material

The frequency inverter is usually connected to the USS bus system by a twisted, shielded two-wire cable.

The guaranteed transfer speeds or transfer distances can only be achieved without errors if the specified cable
parameters are complied with.

Structural Details:

2

Cable diameter : 2 0,5 mm
Flexible strand: 16 0,2 mm
Twisting: 20 twists / m
Total shielding: Mesh, tinned copper wire,

1.1 mm2,

85 % visual covering
Total diameter: 5 mm
External sheath: according to requirements for

flammability, combustion residues,

etc.

Thermal / Electrical Properties:

Conductor resistance (20°C): 40 W/km
Insulation resistance (20°C): 200 W/km
Operating voltage (20°C): 300 V
Test voltage (20°C): 1500 V
Temperature range: -40 °C T 80 °C
Load capacity: 5 A
Capacitance: 120 pF/m

24 Subject to technical amendments BU 0050 GB-3111

1.4 USS - Bus structure

1.4.4.2 Cable runs / Shielding (EMC)

If EMC measures are not in place, high-frequency interference which is principally brought about by switch
procedures or lightning often causes electronic components in the Bus participants to become faulty and error­free operation can no longer be ensured.

Proper shielding of the bus cable reduces the electrical interference which can arise in an industrial
environment. Best shielding characteristics can be achieved with the following measures

 Connect the Bus participants with the shortest amount of cable possible.
 The shielding of the Bus cable must be applied completely and to a wide area on both sides. *
 Avoid using spur lines to connect field devices to the Bus.
 Avoid extending the Bus lines using plug connectors.

Bus lines should be laid with a minimum spacing of 20cm to other lines which carry a voltage higher than 60V.
This applies to lines laid inside and outside of control cabinets.

*)Note: If earthing potential values are different, transient currents may flow through shielding which

is connected on both sides. This may be a danger to electronic components. Differences in
potential must be reduced using adequate potential equalisation.

1.4.4.3 Bus termination

The bus lines be terminated at both ends.
For this, a resistance of 120 must be connected between the data signal lines RS485 + and RS485 - on the

first and last participant.
With some modules, the termination resistor can be switched in with DIP switches. As delivered, the bus

termination resistor is not activated.
If the bus termination resistor is not integrated into the module, it must be installed in the module or the

connector housing.

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MASTER

SLAVE

Parameter order

Control word + Setpoint

Parameter response

Status word + Actual value

PKW section

PZD section

Order telegram

Response telegram

Processing

1.5 Data transmission

1.5.1 Structure of reference data

This section describes the cyclic data traffic between the master and the frequency inverter.
The reference data is divided into two sections:

 PKW section (Parameterisation; Parameter Identification- Value)
 PZD section (Processdata)

Parameter values can be read and written via the PKW section of the reference data. All tasks which are
carried out via the PKW interface are essentially tasks for configuration, monitoring or diagnosis.

The PZD section serves to control the frequency inverter. The control word or status word as well as the
setpoint and actual values are transferred in the process data.

Access always consists of an order and a response telegram. In the order telegram, the reference data is
transferred to the slave. In the response telegram, the reference data is transferred from the slave to the
master. The structure of both telegrams is identical.

Telegram traffic / structure of reference data area

Processing of the process data is carried out immediately in the FI (high priority), in order to ensure a rapid
reaction to control commands or a change in status can be transmitted to the master without delay.

On the other hand, the processing speed of the PKW data has a lower priority, so that processing may take
considerably longer.

26 Subject to technical amendments BU 0050 GB-3111

1.5 USS - Data transfer

Type

Task

PPO1

extended parameter data telegram with 32 bit parameter values and process data

PPO2

Telegram with extended process data (main and two auxiliary setpoint values) and 32 bit parameter value

PPO3

Process data telegram with main setpoint value without parameter data

PPO4

extended process data telegram with main and auxiliary setpoint values without parameter data

PPO

Parameter Process data Object

STW

Control word

PKW

Parameter identifier Value

ZSW

Status word

PZD

Process data

SW1..3

Setpoints 1-3

PKE

Parameter identifier

IW1..3

Actual values 1-3

IND

Index

PWE

Parameter Value

NOTE

Because of the protocol specification, for PPO types 2 and 4 6 words must be reserved for

the address area of the process data (PZD). The two last words are not used for the process
data telegrams and are therefore merely reserve areas.

1.5.2 PPO types

For cyclic data traffic, the Parameter- Process data Object (PPO) with which the process data (PZD) and
parameters (PKW) are transferred from the master to the frequency inverter is defined. The frequency
inverter can process PPO types 1, 2, 3 or 4.

PPO3 and PPO4 are purely process data objects for applications which do not require parameter
processing.

Abbreviations used:

Note:: An SPS can normally only consistently transfer double words by means of I/O memory access.

For longer data formats (PKW channel always / PZD data with PPO2 or PPO4) system functions
(e.g. SFC 14, consistent data reading / SFC15, consistent data writing) must be used.

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PKW

PZD

PKE

IND

PWE

PWE

PZD1

PZD2

PZD3

PZD4

STW

SW1

SW3

SW2

ZSW

IW1

IW3

IW2

1st word

2nd word

3rd word

4th word

5th word

6th word

7th word

8th word

PPO 1

PPO 2 1st word

2nd word

3rd word

4th word

PPO3

PPO4

PKW

PZD

PKE

IND

PWE

PWE

PZD1

PZD2

PZD3

PZD4

STW

SW1

SW2

SW3

ZSW

IW1

IW2

IW3

1st word

2nd word

3rd word

4th word

5th word

6th word

7th word

8th word

PPO 1

PPO 2 1st word

2nd word

3rd word

4th word

PPO3

PPO4

1.5.2.1 PPO types SK 300E/700E/750E

The following diagram shows an overview of the supported PPO types.

1.5.2.2 PPO types for SK 500E series

The following diagram shows an overview of the supported PPO types. Please not the arrangement of
SW2/SW3 and IW2/IW3

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1.5 USS - Data transfer

1st word

2nd word

3rd word

4th word

PZD area with 
1x16 bit setpoint

STW
ZSW

SW1

IW1

PZD area with up to 3
16 bit setpoints

STW
ZSW

SW1

IW1

SW3

IW3

SW2

IW2

PZD area with 1x 32-Bit setpoint
and 1x 16-Bit

STW
ZSW

SW1

IW1

SW2

IW2

1st word

2nd word

3rd word

4th word

PZD area with
1x16 bit setpoint

STW
ZSW

SW1

IW1

PZD area with up to 3
16 bit setpoints

STW
ZSW

SW1

IW1

SW2

IW2

SW3

IW3

Note: 32-Bit setpoints consist of High and Low words (16-Bit each).

1.5.3 Process data (PZD)

In the process data area PZD, control words and setpoints are transferred from the master to the slave
(frequency inverter) and in return, status words and actual values are sent from the slave to the master. The
structure of the PZD area is always the same in terms of the sequence of its elements (words), however,
dependent upon direction of data Master  Slave / Slave  Master, it is designated differently

The process data area of the reference data has the following structure:

- STW: Controlword; length 16 Bit, order telegram
contains control bits (e.g. enable, quick stop, error acknowledgement)

- ZSW: Statusword; length 16 Bit, response telegram
contains status bits (e.g. FI running, error)

- SW1..3: Setpointvalues; maximum of 3 possible, 16 or 32Bit, order telegram
e.g. frequency setpoint value, position setpoint value, torque setpoint value

- IW1..3: Actualvalues; maximum of 3 possible, 16 or 32Bit, response telegram
e.g. actual frequency value, actual position value, actual torque value

1.5.3.1 Process data for SK 300E/700E/750E

1.5.3.2 Process data for SK 500E (entire series)

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PZD1

PZD2

PZD3

PZD4

STW

SW1

SW2/3

SW2/3

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

Bit

Value

Meaning

Comments

0 0 OFF 1

Reverse with the brake ramp, with disconnection from supply at f=0Hz

1 ON

Ready for operation

1 0 OFF 2

Cut off voltage; the inverter output voltage is switched off; the FI enters a state
where switching on is disabled.

1 Operating condition

OFF 2 is cancelled

2 0 OFF 3

Quick stop with programmed quick stop time; with disconnection from supply at
f=0Hz; the FI switches to starting disabled condition.

1 Operating condition

OFF 3 is cancelled

3 0 Disable operation

Cut off voltage; the inverter output voltage is switched off; the FI enters a state
where switching on is enabled.

1 Enable operation

The output voltage is enabled; ramp to the existing setpoint

4 0 Lock ramp generator

Ramp generator is set to zero; no disconnection from supply at f=0Hz; FI remains
in the operation enabled state.

1 Operating condition

Enable ramp generator

5 0 Stop ramp generator

The setpoint currently provided by the ramp generator is "frozen" (frequency is
maintained).

1 Enable ramp generator

Enable setpoint on ramp generator

6 0 Disable setpoint

Selected setpoint value is set to zero on the ramp generator.

1 Enable setpoint

Selected ramp generator setpoint is activated.

7 0 No acknowledgement

With the switch from 0 to 1, errors which are no longer active are acknowledged.

1 Acknowledge

Note: When a digital input has been programmed for the "ack.fault" function, this
bit must not permanently be set to 1 via the bus (otherwise, edge evaluation
would be prevented).

8 0

1 Bit 8 active

Bus bit 8 from the control word is set. (Only for SK 200E and SK 500E)
For further details of the function please refer to parameter (P480).

9 0

1 Bit 9 active

Bus bit 9 from the control word is set. (Only for SK 200E and SK 500E)
For further details of the function please refer to parameter (P480).

10 0 PZD invalid

The transmitted process data is invalid.

1 PZD valid

Valid process data is transferred from the master.
Note:If setpoints only are transferred via the bus, this bit must be set so that the

transferred setpoint is valid.

11 0

1 Rotational direction:

right

Rotational direction right (priority) ON*

12 0

1 Rotational direction:

left

Rotational direction left ON*

13

0/1 Reserved

14

0/1

Bit 0 to switch
parameter set

00 = Parameter set 1
01 = Parameter set 2

10 = Parameter set 3
11 = Parameter set 4

15

0/1

Bit 1 to switch
parameter set

Table 14

1.5.3.3 Control word (STW)

The control word (STW) is the first word transferred to the frequency inverter in the process data area in an
order telegram. For example, a control word "Ready for switch-on" corresponds to 047E

(hex)

.

* If Bit 12=0, then "Direction of rotation right ON" applies

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1.5 USS - Data transfer

PZD1

PZD2

PZD3

PZD4

ZSW

IW1

IW2/3

IW2/3

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

Bit

Value

Meaning

Comments

0 0 Not ready to start

1

Ready to start

Initialisation completed, charging relay ON, output voltage disabled

1 0 Not ready for operation

Causes: No command has been activated, fault is signaled, OFF2 or OFF3
activated, starting disabled state activated

1 Ready for operation

ON command activated, no faults present. The inverter can be started with the
command ENABLE OPERATION

2 0 Operation disabled

1

Operation enabled

The output voltage is enabled; ramp to the existing setpoint

3 0 No fault

1 Fault

Drive fault resulting in stoppage; this state is changed to starting disabled after
the fault has been successfully acknowledged

4 0 OFF 2

OFF2 command applied

1 No OFF 2

5 0

OFF 3

OFF3 command applied

1 No OFF 3

6 0 Starting not disabled

1 Starting disabled

Switches first to OFF1, then to ready-to-start status

7 0 No warning

1

Warning

Drive operation continues, no acknowledgement necessary

8 0 Actual value not O.K.

Actual value does not match the setpoint (with POSICON: failure to reach
setpoint position)

1 Actual value O.K.

Actual value matches required setpoint (setpoint has been reached)
(with POSICON: setpoint has been reached)

9 0 Local guidance

Guidance on local device has been activated

1 Guidance requested

The master has been requested to assume guidance.

10 0

1 Bit 10 active

Bus bit 10 from the status word is set. For further details of function, please refer
to parameter P481.

11 0

1 Rotational direction:

right

Inverter output voltage is turning right

12 0

1 Rotational direction:

left

Inverter output voltage is turning left

13 0

1 Bit 13 active

Bus bit 13 from the status word is set. For further details of function, please refer
to parameter P481.

14

0/1

Currently active
parameter set 0

00 = Parameter set 1
01 = Parameter set 2

10 = Parameter set 3
11 = Parameter set 4

15

0/1

Currently active
parameter set 1

1.5.3.4 Status word (ZSW)

In the inverter response telegram, in the area of the process data the status word (ZSW) is transferred as the
first word. For example, the status word "Ready for switch-on" corresponds to 0B31

(hex)

.

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Bit

Value

Meaning

Comments

10 0 MFR 1 reference value

undershot

Programmed function of the MFR 1 not met or  actual value < programmed
reference value

1 MFR 1 reference value

reached

Programmed function of the MFR 1 is fulfilled, or
Actual value > programmed reference value

13 0 MFR 4 reference value

undershot

Only for SK 700E/750E with POSICON extension: Status MFR 4 = 0

1 MFR 4 reference value

reached

Only for SK 700E/750E with POSICON extension: Status MFR 4 = 1

PZD1

PZD2

PZD3

PZD4

STW

SW1

SW2/3

SW3/2

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

Deviations in the status word (ZSW) for SK 300E and SK 700/750E series devices

With the above device types, the meanings of the two bits 10 and 13 in the status word deviate from the
status word of the SK 500 E.

Meaning of the two individual bits:

1.5.3.5 Setpoint 1 (SW1)

The function of the 1st setpoint is set in parameter P546. The following options are available:

Setpoint frequency
The setpoint frequency in setpoint 1 is transferred as a 16 Bit value as standard. Setpoint 1 is transferred to

the inverter as the second word in the process data area in the order telegram.

The setpoint is transferred as a whole number with a value range of -32768 to 32767 (8000 hex to 7FFF hex).
The value 16384 (4000 hex) is equal to 100%. The value C000 HEX corresponds to -100%. A setpoint of
100% corresponds to the parameter maximum frequency (parameter P105) set in the same parameter set.

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1.5 USS - Data transfer

PZD1

PZD2

PZD3

PZD4

STW

SW1, 32 Bit

SW2

SK 700E/750E

POSICON

P546=3, 32bit setpoint position

SW1, 16 Bit

SW2, 16 Bit

SW3

SK 53xE

P546=21 (23)

Low word

P547=22 (24)

High word

P546[-01]=21

(23)

Low word

P546[-02]=22

(24)

High word

SK 54xE

SK 700E + SK TU1-POS

Bit

Function

Bits 0-5

Position array/position increment

Bit 6

Reference point run

Bit 7

Reference point

Bit 8

Teach-in

Bit 9

Quit teach-in

Bit 10

Reset position

SK 500E

Bit

Function

Bits 0-3

Position array/position increment

Bits 4-7

Vacant

Bits 8-15

no significance

Setpoint position (16 or 32 Bit)

With the special extension Posicon (SK XU1-POS) of the SK 700E the absolute setpoint position can be
transferred as a 16 or 32 Bit value in Setpoint 1, whereby the resolution is 1=0.001 rotation. In addition, the
control terminals (setting of POSICON control bits) can be transferred in binary.

The SK 53xE / SK54xE version of the SK 500E series is also able to transfer positions, however here, the
32 Bit position is divided into two 16 Bit components (Low word and High word). The assignment of the two
16 Bit components is then carried out via appropriate parameterisation on 2 arbitrary setpoints (e.g.: SW1
and SW2).

16-Bit setpoint position setting:

As a 16 Bit value, a range of +32767 (= 32,767 revolutions) to -32768 (= -32,768 revolutions) is possible.
The 16 Bit setpoint position is transferred as the second word in the process data area (as with the setpoint
frequency)

32-Bit setpoint position setting:

As a 32 Bit value, the full position range of +/- 50000,000 revolutions is available. With the SK 700E/750E,
the 32 Bit setpoint position is transferred in the area of the process data as the second and third word (with
the SK 500E in any two of the three words PZD2, PZD3, PZD4).

Control Bit settings POSICON (SK 700E/750E/53xE):

A 16 Bit value is transferred in which the control terminals of the POSICON special extension unit are
mapped. The setpoint position is based on the position array or position increment as per (P610).

The transferred Bits have the following meaning (see Manual BU 710 / BU 0510):

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PZD1

PZD2

PZD3

PZD4

STW

SW1

SW3

SW2

PZD1

PZD2

PZD3

PZD4

STW

SW1

SW2

Setting

100% is equal to

Off

Setpoint frequency, actual frequency PID, actual
frequency PID limited, actual frequency PID monitored,
frequency addition, frequency subtraction, maximum
frequency

Maximum frequency (P105)

Torque current limit

Torque current limit (P112)

Current limit

Inverter rated current

Servo mode torque

Nominal torque (P112)

Lead torque

Lead torque (P214)

1.5.3.6 Second and third setpoint (SW2/3)

With the SK 500E, the assignment of setpoints 2 and 3 to the process data words PZD3 and PZD4 is carried
out in the opposite manner to the SK 300E/700E/750E series.

Second and third setpoint SK 300E/SK 700E/SK 750E(SW2/3)

If the PPO type 2 or 4 is used, in addition to setpoint 1, a 2nd setpoint can be transferred in word PZD4 and
a 3rd setpoint in PZD3.

A third setpoint value can only be transferred if a 32 Bit setpoint value is not transferred in the first setpoint.

The second and third setpoints are always 16 Bit. The function of the second and third setpoints can be set
in the inverter with parameter P547 „'Setpoint function 2‟ and P548 „'Setpoint function 3‟ respectively.

Both setpoints are transferred as whole numbers in the range (-32768 to 32767). The value 16384 (4000
HEX) corresponds to 100%. The value C000 HEX is equal to –100%, so that setpoints in the range
–200% to +200% can be transferred. A setpoint of 100% corresponds to the respective nominal value:

In addition, POSICON control bits can be transferred here (see setpoint 1)

34 Subject to technical amendments BU 0050 GB-3111

1.5 USS - Data transfer

PZD1

PZD2

PZD3

PZD4

STW

SW1

SW2

SW3

Setting

100% is equal to

Off

Setpoint frequency, actual frequency PID, actual
frequency PID limited, actual frequency PID monitored,
frequency addition, frequency subtraction, maximum
frequency

Maximum frequency (P105)

Torque current limit

Torque current limit (P112)

Current limit

Inverter rated current

Servo mode torque

Nominal torque (P112)

Lead torque

Lead torque (P214)

Second and third setpoint SK 500E (SW2/3)

In addition to setpoint 1, a second setpoint can be transferred in word PZD3 and a third setpoint in PZD4.

The second and third setpoints are always 16 Bit. The function of the second and third setpoints can be set
in the inverter with parameter P547 „Setpoint 2 function‟ and P548 „Setpoint 3 function‟ respectively.

Both setpoints are transferred as whole numbers in the range -32768 to 32767. The value 16384 (4000
HEX) corresponds to 100%. The value C000 HEX is equal to –100%, so that setpoints in the range
–200% to +200% can be transferred. A setpoint of 100% corresponds to the respective nominal value:

BU 0050 GB-3111 Subject to technical amendments 35

NORD USS and Modbus RTU Manual

PZD1

PZD2

PZD3

PZD4

ZSW

IW1

IW2/3

IW3/2

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

SK 700E/750E

Bit

Status

Bits 0-5

Digital input 1-6

Bits 6-11 for POSICON special extension unit

Digital input 7-12

Bit 6 for encoder special extension unit

Digital input 7

Bits 12-15

Multifunctional relay 1-4

SK 500E

Bit

Status

Bits 0-4

Digital input 1-5

Bits 5-6 (above SK 520E)

Digital input 6-7

Bits 12-15

Relay and digital outputs 1 - 4

PZD1

PZD2

PZD3

PZD4

ZSW

IW1

IW2

1.5.3.7 Actual value 1 (IW1)

The actual value 1, i.e. the actual output frequency of the inverter, is transferred as a 16 Bit value as
standard in the actual value 1. The actual value 1 is transferred to the master in the inverter response
telegram as the second word in the process data area.

The actual value 1 is transferred as a whole number in the range (-32768 to 32767). In addition to the actual
frequency, other actual inverter values can be transferred. The setting is made in P543 'Actual value 1
function'.

The settings „Actual frequency‟, „Actual speed‟, „Current‟ and „Torque current‟ are transferred as percentages

of the respective nominal values. The value 16384 (4000 HEX) corresponds to 100%. The value C000 HEX
corresponds to -100%. Actual values in the range –200% to +200% can be transferred.

With the setting „Digital I/O status‟, the states of the control terminals and the relay (MFR) /digital outputs can
be transferred:

With the setting 'Actual position' and 'Setpoint position' the actual absolute position is transferred. The
resolution is 1 = 0.001 revolutions.

If with SK 700E/750E the value 'Setpoint position 32 Bit' is set in parameter P546 (Setpoint function 1), then
the actual value (setpoint or actual position) is also transferred as a 32 Bit value in PZD2 and PZD3:

1.5.3.8 Actual value 2 and actual value 3 (IW2/3)

It is possible to forward two more actual values to the controller if PPO type 2 or 4 is used for transfer.
The assignment of the actual values 2 and 3 to the process data words PZD3 and PZD4 is carried out in the

same way as the assignment of setpoints 2 and 3. These also differ in sequence between the SK 500E and
other inverter series.

36 Subject to technical amendments BU 0050 GB-3111

1.5 USS - Data transfer

Status

Bit 6

Switch-on

disable

Bit 5

Emergency

stop

Bit 4

Disable

voltage

Bit 3

Fault

Bit 2

Operation

enabled

Bit 1

Standby

Bit 0

Ready for

switch-on

Not ready to start

0 X X 0 0 0 0

Starting disabled

1 X X 0 0 0 0

Ready to start

0 1 1 0 0 0 1

Activated

0 1 1 0 0 1 1

Operation enabled

0 1 1 0 1 1 1

Fault

0 X X 1 0 0 0

Error active

0 X X 1 1 1 1

Emergency stop active

0 0 1 0 1 1 1

Second and third actual value SK 300E/SK 700E/SK 750E(SW2/3)

The actual value 2 (IW2) is transmitted in PZD4. The value to be transferred can be selected in P544 (actual
bus value 2). Actual value 3 (IW3) can be transmitted in PDZ3 if actual value 1 is not a 32 Bit value. The
value to be transferred can be selected in P545 (actual bus value 3).

Second and third setpoint SK 500E (SW2/3)

The actual value 2 (IW2) is transmitted in PZD3. The value to be transferred can be selected in P544 (actual
bus value 2). The actual value 3 (IW3) is transmitted in PZD4. The value to be transferred can be selected in
P545 (actual bus value 3).

1.5.3.9 The status machine

The frequency inverter passes through a status machine. The changes between various states are triggered
by the respective control commands in the process data control word. The actual status is returned in the
process data status word.

After switching on, the inverter is in switch-on disabled status. This status can only be ended by
transmitting the “Shut down (Off 1)” command.

The answer to a Master telegram normally does not yet contain a reaction to the control command. The
controller must check the answers from the slaves as to whether the control command has been carried out.

The following Bits indicate the status of the frequency inverter:

BU 0050 GB-3111 Subject to technical amendments 37

NORD USS and Modbus RTU Manual

Switch-on

disabled

Ready for
sw itch-on

Activated

Operation

enabled

Emergency stop

active

Error reaction

active

Error

From any device status

3 4 5 6 8

4 5

5

Not on standby

Switching on theinverter

Loading relay applied

Error

Error reaction complete

Bit0 = 0: Shut down
& Bit1 = 1: Enable voltage
& Bit2 = 1: Enable pulses
(xxxx x1xx xxxx x110)

Bit 3 = 0: Disable operation Bit0 = 1: Switch on

Bit3 = 1: Enable operation

Bit2 = 0: Emergency stop

Bit1 = 0: Disable voltage

v Bit2 = 0:Emergency stop

Priority of control commands:

1. Disable / enable voltage

2. Emergency stop

3. Shut down

4. Enable operation

5. Switch on

6. Disable operation

7. Reset error

Coding of status:

1: Bit 0 = 0
2: Bit 6 = 1
3: Bit 0 = 1
4: Bit 1 = 1
5: Bit 2 = 1
6: Bit 5 = 0
7: Bit 2 & Bit 3 = 1
8: Bit 3 = 1

3

5

2 3

3 64

2

2

1

2

3

7

8

f = 0 reached
(emergency stop complete)

Bit701

Error acknowledgement

Control bits

0. Standby / Shut dow n

1. Disable / enable voltage

2. Enable pulses / emergency stop

3. Disable / enable operation

4. Betriebsbedingung / HLGsperren

5. Enable / stop RUE

6. Enable / disable setpoint

7. Error acknowledgement (01)

10. Control data valid / invalid

11. Direction of rotation clockwise

12. Direction of rotation anticlockwise

14. Parameter set Bit 0

15. Parameter set Bit 1

4

5

6

Bit4 = 0: Move dow n emergency stop ramp and

remain in'Operation enabled'

Bit5 = 0: Hold frequency
Bit6 = 0: Setpoint = 0%

Bit0 = 0: Shut down

5

Bit3 = 1: Enable operation

& Bit0 = 1: Switch on

2

Internal status machine

2

38 Subject to technical amendments BU 0050 GB-3111

1.5 USS - Data transfer

NOTE

If parameter changes are made i.e. parameter identifier values (PKW), care must be taken that

the maximum number of permissible writing cycles to the frequency inverter EEPROM (100,000
cycles) is not exceeded. I.e. continuous cyclical writing must be prevented. For certain
applications it is sufficient if the values are only saved in the RAM memory of the frequency
inverter. For further details se Saving in the EEPROM under Parameter P560 in the frequency
inverter manual.

1 2 3 4

PKE

IND

PWE1

PWE2

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

SPM

AK

PNU

1.5.4 Parameter range (PKW)

Using the PKW mechanism, parameter processing can be carried out in the cyclical data traffic. For this the
master formulates an order and the inverter formulates the response to this. The parameter area is only used
for transfer with PPO type 1 and PPO type 2.

In principle, the parameter range consists of a parameter identification, in which the type of order (Write,
Read etc.) and the relevant parameters are specified. Individual parameter sets or array elements can be
addressed with the aid of the Index. The parameter value contains the value to be written or read.

Note: A parameter order must be repeated until the inverter responds with the corresponding response

telegram.

1.5.4.1 Parameter label (PKE)

The order or response and the associated parameters are encrypted in the parameter label (PKE).

The parameter label (PKE) is always a 16 bit value.
PNU: The bits 0 to 10 contain the number of the required parameter (PNU),or the number of the current

parameter in the response parameter from the inverter.

Note: For the inverter parameter numbers (PNU) of the particular inverter series please refer to the

relevant operating instructions for the inverter.

SPM: Bit 11 is the toggle-bit for spontaneous messages. This function is not supported!
AK: Bits 12 to 15 contain the order or response label.

BU 0050 GB-3111 Subject to technical amendments 39

NORD USS and Modbus RTU Manual

AK

Function

Response label positive

0

No order

0 1 Order parameter value

1 / 2

2

Change parameter value (word)

1

3

Change parameter value (double word)

2 4 Reserved

- 5 Reserved

-

6

Order parameter value (array)

4 / 5

7

Change parameter value (array word)

4

8

Change parameter value (array double word)

5

9

Order the number of array elements

6

10

Reserved

-

11

Change parameter value (array double word)
without writing into EEPROM

5

12

Change parameter value (array word)
without writing into EEPROM

4

13

Change parameter value (double word)
without writing into EEPROM

2

14

Change parameter value (word)
without writing into EEPROM

1

AK

Function

0

No response

1

Transfer parameter value (word)

2

Transfer parameter value (double word)*

4

Transfer parameter value (array word)

5

Transfer parameter value (array double word)*

7

Order cannot be executed (with error number in PWE2)

The following table lists all the orders which can be transferred from the master to the inverter. The right­hand column contains the response, which is normally sent (response label positive). Only certain response
labels are possible, depending on the order label. In case of error (response label negative) the inverter will
always supply the value 7 in the response label (AK) to the master.

Meaning of the values sent in the response label:

* Only for PPO type 2 and PPO type 4

As long as an order has not yet been executed, the inverter provides the response to the last order.
Therefore the master must always check whether the received response matches the order sent.
For the plausibility check, the value in the response label (AK), the received parameter number (PNU) with
the corresponding Index (IND) as well as the current parameter value (PWE) can be used for the description
of parameters.

40 Subject to technical amendments BU 0050 GB-3111

1.5 USS - Data transfer

No.

Meaning

0

Invalid parameter number

1

Parameter value cannot be changed

2

Lower or upper value limit exceeded

3

Incorrect sub-index

4

No array

5

Invalid data type

6

Only resettable (only 0 may be written)

7

Description element cannot be changed

9

Description data not present

201

Invalid order element in the last order received

202

Internal response label cannot be depicted

1 2 3 4

PKE

IND

PWE1

PWE2

15

14

13

12

11

10 9 8 7 6 5 4 3 2 1 0

No information / all 0

P1-P4 Array 1-64

P1-P4

Sub-index

Array 1-256

Array element

Parameter set

Index

5 (000101

BIN

)

2 (01

BIN

)

15

HEX

= 0001 0101

BIN

21 (010101

BIN

)

4 (11

BIN

)

57

HEX

= 0101 0111

BIN

Error messages if the order cannot be executed
If the response label is "Order cannot be executed" (AK = 7), then an error message is added to the

parameter value (PWE2) of the inverter response. For the meanings of the transferred values , please refer
to the following table.

1.5.4.2 Sub-index (IND)

The structure and function of the parameter index (IND) depends on the type of parameter to be transferred.
For values which depend on the parameter set, the parameter set can be selected via Bits 0 and 1 of the

Index (IND) (0 = parameter set 1, 1 = parameter set 2,...).
If the parameter to be processed is also an array parameter (e.g. position array for the POSICON option),

then the sub-index of the required parameter can additionally be accessed via Bit 2 to Bit 7 of the sub-index
(0 = array element 1, 1 = array element 2,…):

If a parameter is not dependent on the parameter set, then Bits 0 -7 are used for the sub-index.
Please refer to the operating instructions for details of the structure of the individual parameters and which

values may be called up.

BU 0050 GB-3111 Subject to technical amendments 41

NORD USS and Modbus RTU Manual

Baud rate

Interval

4800 Baud

100 ms

9600 Baud

50 ms

19200 Baud

25 ms

38400 Baud

15 ms

1.5.4.3 Parameter value (PWE)

According to the type of the PPO or parameter, transfer of the parameter value (PWE) is always as a word
(16 Bit) or double word (32 Bit) Only one parameter value can be transferred in a telegram.

A 32 bit parameter value comprises PWE1 (high value word) and PWE2 (low value word, 4th word).
A 16 Bit parameter value for PPO1 and PPO2 is transferred in PWE2. For negative values the High word

must be set to FFFF hex.
Note: 32-Bit parameter values are only used with the POSICON option. All the relevant parameters are

described in the POSICON supplementary manual.

The parameter value is transferred as an integer value. For parameters with resolutions 0.1 or 0.01 the
parameter value must be multiplied by the inverse of the resolution.

Example: A start-up time of 99.99 seconds is to be set:

99.99s  99,99 * 1/0.01 = 99.99 * 100 = 9999. Therefore the value 9999

= 270F

dec

must be transferred.

hex

1.5.4.4 Master Function Output

With a setting in parameter P503, the inverter control signals (digital and/or analog) which are to be output as
a bradcast telegram (type PPO3/PPO4) in USS protocol format via the RS 485 interface can be selected.
The control source is still selected in P509. The transfer intervals depend on the USS baud rate which is set:

42 Subject to technical amendments BU 0050 GB-3111

1.6 USS – Telegram examples

1.6 Telegram examples

Various example telegrams are shown below to clarify the control and parameterisation of the frequency
inverter with the USS protocol.

Note: When transferring parameter orders, it must be taken into account that the slave does not

immediately respond to orders in the parameter channel of the master telegram, but a positive
response can be delayed by one or more communication cycles. The master must therefore repeat
the required order until the corresponding slave response is received.

The macro generator of the NORD CON control and parameterisation software is used as a programming aid.
The macro generator is started directly from the NORD CON program via the menu bar.

1.6.1 The Macro Generator

Simple process sequences can be simulated with the aid of the macro generator. This can used for instance,
for testing during commissioning. Parameterisation of the devices is also possible. The individual telegrams of
a macro are shown in hexadecimal format. This information can be used to create control programs based on
the USS protocol.

A macro can consist of several steps. The telegram wich is transferred to the inverter can be observed in the
Hex view in the overview. A sub-menu provides help for creating the individual steps.

 USS address
 Control word
 Setpoint
 Parameter number
 Parameter index
 Parameter value
 Order

Together, all of these steps comprise a step in the macro The telegram structure in the Hex view of each
individual step is shown in the Macro window.

BU 0050 GB-3111 Subject to technical amendments 43

NORD USS and Modbus RTU Manual

Byte No.

0 1 2 3 4 5 6 7 8

9

10

11

12

13

Meaning

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

Hexadecimal

02

0C

00

00

00

00

00

00

00

0B

70

00

00

75

Bit

Value

Value

HEX

Meaning

15

0 0 Parameter set Bit 1 off

14 0 Parameter set Bit 0 off

13 0 Reserved

12 0 Rotation left is off

11

1 B Rotation right is on

10 0 Reference value undershot

9 1 Bus controller

8 1 Setpoint = actual value

7

0 7 No warning

6 1 Starting disabled

5 1 No emergency stop

4 1 Disable voltage

3

0 0 No fault

2 0 Operation disabled

1 0 Not ready for operation

0 0 Not on standby

0 1 2 3 4 5 6 7 8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

STW

STW

SW1

SW1

BCC

02

0C

00

00

00

00

00

00

00

04

7E

00

00

74

Abbreviations used:

PKW Parameter identifier Value
PZD Process data
PKE Parameter identifier
IND Index
PWE Parameter Value
STW Control word 1
ZSW Status word 1
SW1..3 Setpoint
IW1..3 Actual value

1.6.2 Switch-on block  Standby

A frequency inverter with the USS address 0 is to be switched from the status "Switch-on disabled"
(STW Bit 0 – 0), which is active when the device is switched on, to the "Standby" status (STW Bit 0 = 1).
Parameter set 1 is valid and no parameter data is transfered.

Procedure:

 Check last status word (ZSW 0A 70)
 Set address (Address 00)
 Generate control word (STW 04 7E)
 Send telegram
 Check response telegram (ZSW 0B 31)

Details:

The status word of frequency inverter  is in switch-on block status

To switch the frequency inverter to the standby status, the following telegram must be sent:

44 Subject to technical amendments BU 0050 GB-3111

1.6 USS – Telegram examples

0 1 2 3 4 5 6 7 8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

02

0C

00

00

00

00

00

00

00

0B

31

00

00

34

Bit

Value

Value

HEX

Meaning

15

0 0 Parameter set Bit 1 off

14 0 Parameter set Bit 0 off

13 0 Reserved

12 0 Rotation left is off

11

1 B Rotation right is on

10 0 Reference value undershot

9 1 Bus controller

8 1 Setpoint = actual value

7

0 3 No warning

6 0 Starting not disabled

5 1 No emergency stop

4 1 Enable voltage

3

0 1 No fault

2 0 Operation disabled

1 0 Not ready for operation

0 1 Ready to start

When the frequency inverter switches to standby status, it sends the following response telegram:

Note: The control telegram must be sent cyclically as the frequency inverter may not switch to the

required status within the response time of a telegram.

BU 0050 GB-3111 Subject to technical amendments 45

NORD USS and Modbus RTU Manual

0

1 2 3 4 5 6 7

8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

02

0C

0A

00

00

00

00

00

00

0B

31

00

00

37

0

1 2 3 4 5 6 7

8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

STW

STW

SW1

SW1

BCC

02

0C

0A

00

00

00

00

00

00

04

7F

20

00

5F

0

1 2 3 4 5 6 7

8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

02

0C

0A

00

00

00

00

00

00

0F

37

20

00

1C

1.6.3 Enable with 50% setpoint

A frequency inverter with the USS address 10, which is in "Standby" status (Section 1.6.2) is to be enabled for
clockwise rotation with 50% setpoint. The last response telegram was received as follows in the controller.

Procedure:

 Check last status word (ZSW 0A 31)
 Set address (Address 0A)
 Generate control word (STW 04 7F)
 Generate setpoint (2000 hex)
 Send telegram
 Check response telegram (ZSW 0F 37)

Details:

Starting requirement (status word of frequency inverter)

The following telegram must be sent to the inverter

The frequency inverter accelerates the motor in the ramp. When the inverter has reached the 50% setpoint, it
responds with the following telegram.

Note: The status of MFR 1 is indicated in Bit 10 of the response telegram. Depending on the

programmed function and status, the status word may differ.

46 Subject to technical amendments BU 0050 GB-3111

1.6 USS – Telegram examples

0

1

2 3 4 5 6 7 8 9 10

11

12

13

14

15

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

PWE

PWE

STW

STW

SW1

SW1

BCC

02

0E

03

20

66

00

01

00

00

03

E8

00

00

00

00

80

0

1

2 3 4 5 6 7 8 9 10

11

12

13

14

15

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

02

0E

03

10

66

00

01

00

00

03

E8

09

31

00

00

88

1.6.4 Writing a parameter

When transferring parameter orders, it must be taken into account that the slave does not immediately respond
to orders in the parameter channel of the master telegram, but a positive response can be delayed by one or
more communication cycles. The master must therefore repeat the required order until the corresponding slave
response is received.

The acceleration time parameter (USS No. = 102
to be set to the value 10sec in parameter set 2. No process data is transferred.

As the acceleration time has an internal inverter resolution of 0.01sec, a parameter value of
10 / 0.01 = 1000 (3E8

) must be transferred. PPO1 was selected as the PPO type.

hex

Procedure:

 Set address (Address 03)
 Select parameter (P 102

dec

/ P 66

hex

)

 Select order label (2 = change parameter value (word))
 Select parameter set 2 (IND = 01)
 Set parameter word (1000

dec

/ 3E8

HEX

)

 Send telegram
 Check response telegram

The telegram is composed as follows in hexadecimal notation:

dec

/ 66

) of a frequency inverter with the USS address 3, is

hex

When the order has been fully implemented by the inverter, it responds with

BU 0050 GB-3111 Subject to technical amendments 47

NORD USS and Modbus RTU Manual

0

1

2 3 4 5 6

7 8 9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

STW

STW

SW1

SW1

BCC

02

0C

03

10

66

00

01

00

00

00

00

00

00

7A

0

1

2 3 4 5 6 7 8

9

10

11

12

13

STX

LGE

ADR

PKE

PKE

IND

IND

PWE

PWE

ZSW

ZSW

IW1

IW1

BCC

02

0C

03

10

66

00

01

03

E8

0B

31

20

00

A8

1.6.5 Reading the acceleration time parameter

The acceleration time parameter (USS No. = 102

dec

/ 66

) in parameter set 2 of a frequency inverter with the

hex

USS address 3, is to be read out. No process data is transferred.

Procedure:

 Set address (Address 03)
 Generate parameter label (PKE 10 66)
 Select parameter set 2 (IND = 01)
 Send telegram
 Check response telegram (PWE = 3E8)

Details:

The response telegram of the slave contains the required parameter value in internal standardisation and
could be as follows:

The value sent in PWE2 is C8

corresponding to 1000

HEX

corresponds to an acceleration time of 1000 * 0.01 = 10 seconds

 10 / 0.01 = 1000 (3E8

, with a resolution of 0.01 seconds, this

DEC

)

hex

48 Subject to technical amendments BU 0050 GB-3111

1.7 USS - Master- Telegram times

Baud

rate

PPO type

Telegram

Bytes

Start pause

time

[msec]

Minimum total

run time

[msec]

Maximum run

time

[msec]

Response delay

time

[msec]

4800

PPO0

14

4,583

32,083

48,1

4,583

4800

PPO1

16

4,583

36,667

55

4,583

4800

PPO2

20

4,583

45,833

68,8

4,583

4800

PPO3 8 4,583

18,333

27,5

4,583

4800

PPO4

12

4,583

27,5

41,3

4,583

9600

PPO0

14

2,292

16,042

24,1

2,292

9600

PPO1

16

2,292

18,333

27,5

2,292

9600

PPO2

20

2,292

22,917

34,4

2,292

9600

PPO3 8 2,292

9,167

13,8

2,292

9600

PPO4

12

2,292

13,75

20,6

2,292

19200

PPO0

14

1,146

8,021

12

1,146

19200

PPO1

16

1,146

9,167

13,8

1,146

19200

PPO2

20

1,146

11,458

17,2

1,146

19200

PPO3 8 1,146

4,583

6,9

1,146

19200

PPO4

12

1,146

6,875

10,3

1,146

38400

PPO0

14

0,573

4,01 6 0,573

38400

PPO1

16

0,573

4,583

6,9

0,573

38400

PPO2

20

0,573

5,729

8,6

0,573

38400

PPO3 8 0,573

2,292

3,4

0,573

38400

PPO4

12

0,573

3,438

5,2

0,573

1.7 Master Telegram Times

The telegram times to be monitored depend on the currently valid baud rate and the telegram length.
For the data format: 8E1, the following running times apply:

The start pause time and the typical response delay time are determined by the transfer time for two bytes of
data. The maximum response time provided by the telegram is 20msec.

The total run time in the table is the consecutive telegram run time, i.e. the stop bit of the last character
immediately follows the start character of the next character. However, in practice there are time delays
between the bytes of a telegram. Therefore the factor 1.5 is used for the maximum telegram run time.

Maximum total run time = 1-5 * consecutive telegram run time

The interface driver software must check or maintain compliance with the following telegram parameters and
trigger an error if they are repeatedly overshot:

 Telegram length details of the received telegram (LGE)
 Telegram format (start character / STX, check-sum / BCC)
 Character format (parity, start and stop bit)
 Total run time of the slave response

Response delay time (typical transfer duration for 2 bytes, max 20 msec)

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Parameter

Setting value / Description / Note

Comments

P480 ..[-01]
...
.. [-12]

Function BusIO In Bits

(Function of Bus I/O In Bits)

0 ... 72
{ 0 }

The Bus I/O In Bits are perceived as digital inputs. They can be set to the same functions as the digital
inputs (See P420…of the respective FI manual).

[-01]= Bus I/O In Bit 0
[-02]= Bus I/O In Bit 1
[-03]= Bus I/O In Bit 2
[-04]= Bus I/O In Bit 3
[-05]= Bus I/O In Bit 4
[-06]= Bus I/O In Bit 5

[-07]= Bus I/O In Bit 6
[-08]= Bus I/O In Bit 7
[-09]= Flag 1 (only SK 500E)
[-10]= Flag 2 (only SK 500E)
[-11]= Bit 8 BUS control word (only for SK 500E)
[-12]= Bit 9 BUS control word (only for SK 500E)

P481 .. [-01]
...
.. [-10]

Function BusIO Out Bits

(Function of Bus I/O Out Bits)

0 ... 39
{ 0 }

The bus I/O Out bits are perceived as multi-function relay outputs. They can be set to the same functions
as the digital inputs (See P434…of the respective FI manual).

[-01]= Bus I/O Out Bit 0
[-02]= Bus I/O Out Bit 1
[-03]= Bus I/O Out Bit 2
[-04]= Bus I/O Out Bit 3
[-05]= Bus I/O Out Bit 4
[-06]= Bus I/O Out Bit 5

[-07]= Bus I/O Out Bit 6 / Flag 1
[-08]= Bus I/O Out Bit 7 / Flag 2
[-09]= Bit 10 BUS status word (only for SK 500E)
[-10]= Bit 13 BUS status word (only for SK 500E)

P482 .. [-01]
...
.. [-10]

Stand. BusIO Out Bits

(Standardisation of Bus I/O Out Bits)

-400 … 400 %
{ 100 }

Adjustment of the limit values of the relay functions/Bus Out Bits. For a negative value, the output
function will be output negative.

When the limit value is reached and the setting values are positive, the relay contact closes, with
negative setting values the relay contact opens.

P483 .. [-01]
...
.. [-10]

Hyst. BusIO Out Bits

(Hysteresis of Bus I/O Out Bits)

1 … 100 %
{ 10 }

Difference between switch-on and switch-off point to prevent oscillation of the output signal.

1.8 Frequency Inverter Settings

1.8.1 Frequency inverter bus parameters

To operate the inverter with the USS protocol, the bus must be connected to the master and some settings
must be made on the frequency inverter.

The frequency inverter can always be parameterised. Control of the inverter via USS can be activated by
setting parameter P509 to value 2, 3 or 4 (for SK 500E to 2) (see below). In order to access the inverter via
the control unit, only the baud rate in P511 and the inverter address P512 need to be set.

The telegram down time P513 can be selected depending on the USS system.

1.8.1.1 Control clamp parameters

50 Subject to technical amendments BU 0050 GB-3111

1.8.1.2 Extra functions

Parameter

Setting value / Description / Note

Comments

P502 ... [-01]

…

... [-05]

Master function value

(Master function value)

SK 5xxE

1 ... 24
{ 0 }

Selection of master values (up to SK 535E: max. 3 master values, SK 540 and above: max. 5
master values:

[-01] = Master value 1

[-02] = Master value 2

[-03] = Master value 3

SK 540E and
above:

[-04] = Master value 4

[-05] = Master value 5

Selection of possible setting values for master values:

0 = Off
1 = Actual frequency
2 = Actual speed
3 = Current
4 = Torque current
5 = State of digital inputs

and outputs

6 = Reserved
7 = Reserved
8 = Setpoint frequency

9 = Error message
10 = Reserved
11 = Reserved
12 = Digital Out Bit 0…7
13 = Reserved
14 = Reserved
15 = Reserved
16 = Reserved
17 = Value analog input 1
18 = Value analog input 2

19 = Setpoint frequency

master value

20 = Setpoint frequency after

master value ramp

21 = Actual frequency without

master value slip

22 = Speed encoder
23 = Actual freq. with slip

(from SW V2.0)

24 = Master value, act. freq.

with slip

(from SW V2.0)

P503

Master function output

(Master function output)

SK 300E, SK 700E, SK 750E

1 ... 6
{ 0 }

To use the master function output, the inverter controller source must be selected in P509. Only
the master frequency (setpoint 1 and control word) is transferred with Mode 1, while the actual
values selected in P543, P544 and P545 are transferred in Mode 2.

In Mode 3 a 32Bit actual position and a 16Bit setpoint speed (after ramp) is output. Mode 3 is
required for synchronous control with the POSICON option.

0 = Off
1 = USS mode 1
2 = CAN Mode 1

up to 250kBaud

3 = USS mode 2
4 = CAN Mode 2

up to 250kBaud

5 = USS mode 3
6 = CAN Mode 3

P503

Master function output

(Master function output)

SK 5xxE

1 ... 5
{ 0 }

To use the Master function output, the inverter controller source must be selected in
P509. The master value to be transmitted is determined via the BUS interface in
parameter P502.

0 = Off

1 = USS

2 = CAN (up to 250kBaud)

3 = CANopen

4 = System bus active

5 = CANopen+Sys.bus act.

P507

PPO Type

(PPO Type)

1 ... 4
{ 1 }

Type of PPO used (see Section 1.5.2 6)

1.8 USS – Frequency inverter settings

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Parameter

Setting value / Description / Note

Comments

P509

Interface

(interface)

SK 300E, SK 700E, SK 750E

0 ... 21
{ 0 }

Selection of the interface from which the inverter is controlled.

0 = Control terminal or keyboard control with the Control Box (option) ,the ParameterBox

(option) or the Potentiometer option

1 = Control terminals only, the inverter can only be controlled via the 4 digital inputs and the

analog input.

2 = USS setpoint, the frequency setpoint is transferred via the USS protocol. Control via the

digital inputs is still active.

3 = USS control word, the control signals (enable, direction of rotation, ...) are transferred via

USS, the setpoint via the analog input or the fixed frequencies.

4 = USS, all control data is transferred via the USS protocol. The analog input and the digital

inputs have no function (except safety functions, see below)

5 = …

P509

Control word source

(Control word source)

SK 5xxE

0 ... 10
{ 0 }

Selection of the interface via which the FI is controlled.

0 = Control terminal or keyboard control with the Control Box (if P510=0), the

ParameterBox (not extension parameter box) or via BUS I/O Bits.

1 = Only control terminals , the FI can only be controlled via the digital and analog inputs or

via the bus I/O Bits.

2 = USS control word: the control signals (enable, direction of rotation, ...) are transferred via

the RS485 interface. The setpoint is transferred via the analog input or the fixed
frequencies.
Above SK 540E this setting should also be selected if communication via Modbus RTU is
intended. The frequency inverter automatically detects whether this is a USS protocol or a
Modbus protocol.

3 = …

P510

Aux. setpoint interface

(Auxiliary setpoints interface)

SK 700E, SK 750E

0 ... 8
{ 0 }

Selection of the interface from which the inverter is controlled.

0 = Auto: The auxiliary setpoint value is automatically

taken from the interface of the main setpoint value
P509 >interface<

1 = USS
2 = CANbus
3 = Profibus

4 = InterBus
5 = CANopen
6 = DeviceNet
7 = Reserved
8 = CAN Broadcast

P510 ... [-01]
... [-02]

Setpoints source

(Setpoints source)

SK 5xxE

0 ... 10
{ 0 }

Selection of the setpoint source to be parameterised.

[-01] = Main setpoint source

[-02] = Auxiliary setpoint source

Selection of the interface via which the FI receives the setpoint.

0 = Auto: the source of the auxiliary

setpoint is automatically derived from
the setting in the parameter P509
>Interface<

1 = Control terminals, digital and analog

inputs control the frequency, including
fixed frequencies

2 = USS (or Modbus RTU above SK 540E)

3 = CAN

4 = Profibus

5 = InterBus

6 = CANopen

7 = DeviceNet

8 = EtherCAT

9 = CAN Broadcast
10 = CANopen Broadcast

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1.8 USS – Frequency inverter settings

Parameter

Setting value / Description / Note

Comments

P511

USS baud rate

(USS baud rate)

0 ... 7
{ 3 }

Setting of the transfer rate (transfer speed) via the RS485 interface. All bus participants must
have the same baud rate setting.

0 = 4800 Baud

1 = 9600 Baud

2 = 19200 Baud

3 = 38400 Baud

4 = 57600 Baud (SK 54xE)

5 = 115200 Baud (SK 54xE)

6 = 230400 Baud (SK 54xE)

7 = 460800 Baud (SK 54xE)

NOTE: For communication via Modbus (available for SK 540E and above) a transfer rate of

maximum 38400 Baud must be set.

P512

USS Address

(USS Address)

0 ... 30
{ 0 }

Setting of the FI bus address for USS (or SK 540E and above: also Modbus) communication.

P513

Telegram downtime

(Telegram downtime)

-0.1 / 0.0 /

0.1 ... 100.0 s
{ 0.0 }

Monitoring function of the active bus interface. Following receipt of a valid telegram, the next one
must arrive within the set period. Otherwise the FI reports an error and switches off with the error
message E010 >Bus Time Out<.

0.0 = Off: Monitoring is switched off.

-0.1 = No error: Even if communication between BusBox and FI is interrupted (e.g. 24V error,

Box removed, etc.), the FI will continue to operate unchanged.

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Parameter

Setting value / Description / Note

Comments

P543 (P)

Bus – Actual value 1

(Bus – Actual value 1)

0 ... 12 (24)
{ 1 }

The return value 1 (IW1) can be set for bus control in this parameter.

SK 300E, SK 700E SK 750E

0 = Off
1 = Actual frequency

2 = Actual speed
3 = Current
4 = Torque current
5 = Status of digital inputs and relay
6 = Actual position (only POSICON,

SK700/750E)

7 = Setpoint position (only POSICON,

SK700/750E)

8 = Setpoint frequency
9 = Error number
10 = Actual position increment 1 (only

POSICON, SK700/750E)

11 = Setpoint position increment 1 (only

POSICON, SK700/750E)

12 = BUS I/O Out Bits 0-7

SK 500E

0 = Off
1 = Actual frequency
2 = Actual speed
3 = Current
4 = Torque current (100% = P112)
5 = State of digital inputs and outputs2
6 = Actual position Low word
7 = Setpoint position Low word
8 = Setpoint frequency

9 = Error number
10 = Actual position increment Low word
11 = Setpoint position increment Low word
12 = Bus I/O Out Bits 0...7
13 = Actual position High word
14 = Setpoint position High word
15 = Actual position increment High word
16 = Setpoint position increment High word
17 = Value analog input 1 (P400)
18 = Value analog input 2 (P405)
19 = Setpoint frequency master value (P503)
20 = Setpoint frequency after master value ramp
21 = Actual frequency without master value slip
22 = Speed from encoder

(only possible with SK 52x/53xE and
encoder feedback)

23 = Actual frequency with slip, "Actual frequency

with slip"

24 = Master value, actual freq. with slip, "Master

value, actual freq. with slip"

NOTE: For SK 540 and SK545E 5 actual values are available. These are all set in

parameter P543, which is divided into 5 array elements for this purpose.
Parameters P544 and P545 are not required for this inverter version.

[-01] = Actual bus value 1

[-02] = Actual bus value 2

[-03] = Actual bus value 3

[-04] = Actual bus value 4

[-05] = Actual bus value 5

P544 (P)

Actual bus value 2

(Actual bus value 2)

except SK 54xE

0 ... 12 (24)
{ 0 }

The return value 2 (IW2) can be set for bus control in this parameter.
For setting values, see parameter (P543)

P545 (P)

Actual bus value 3

(Actual bus value 3)

except SK 54xE

0 ... 12 (24)
{ 0 }

In this parameter, the return value 3 (IW3) can be set for bus control. This is only available if P546 
3 (only applies for SK 700E / SK 750E).

For setting values, see parameter (P543)

1

2

An indicated revolution of the motor results from 8192 encoder increments.

The assignment of the digital inputs in P543/ 544/ 545 = 5

Bit 0 = DigIn 1 Bit 1 = DigIn 2 Bit 2 = DigIn 3 Bit 3 = DigIn 4
Bit 4 = DigIn 5 Bit 5 = DigIn 6 Bit 6 = DigIn 7 Bit 7 = Reserved
Bit 8 = Reserved Bit 9 = Reserved Bit 10 = Reserved Bit 11 = Reserved
Bit 12 = Out 1 Bit 13 = Out 2 Bit 14 = Out 3 Bit 15 = Out 4

54 Subject to technical amendments BU 0050 GB-3111

1.8 USS – Frequency inverter settings

Parameter

Setting value / Description / Note

Comments

P546 (P)

Function Bus setpoint 1

(Function of bus setpoint 1)

0 ... 7 (47)
{ 1 }

In this parameter, a function is assigned to the delivered setpoint 1 (SW1) for bus control.

NOTE: Further details can be found in the respective FI manual or in the description of P400.

SK 300E, SK 700E SK 750E

0 = Off
1 = Setpoint frequency (16 bit)
2 = 16 Bit setpoint position

(only POSICON SK700/750E)

3 = 32 Bit setpoint position

(only POSICON, SK700/750E and if
PPO- type 2 or 4 are selected)

4 = Control terminals POSICON (only

POSICON, SK700/750E, 16Bit)

5 = Setpoint position (16 Bit) increment 1

(onlyPOSICON, SK700/750E)

6 = Setpoint position (32 Bit) increment 1

(onlyPOSICON, SK700/750E)

7 = Bus IO In Bits 0-7

SK 500E

0 = Off
1 = Setpoint frequency (16 bit)
2 = Torque current limit (P112)
3 = Actual frequency PID
4 = Frequency addition
5 = Frequency subtraction
6 = Current limit (P536)
7 = Maximum frequency (P105)
8 = Actual PID frequency limited
9 = Actual PID frequency monitored

(SK 530E and above)
(SK 530E and above)
(SK 530E and above)
(SK 530E and above)

NOTE: For SK 540 and SK545E 5 setpoints are available. These are all set in parameter

P546, which is divided into 5 array elements for this purpose. Parameters P547
and P548 are not required for this inverter version.

[-01] = Bus setpoint 1

[-02] = Bus setpoint 2

[-03] = Bus setpoint 3

[-04] = Bus setpoint 4

[-05] = Bus setpoint 5

P547 (P)

Function Bus setpoint 2

(Function of bus setpoint 2)

except SK 54xE

0 ... 46 (47)
{ 0 }

In this parameter, a function is assigned to the delivered setpoint 2 (SW2) for bus control.

0 = Off
1 = Setpoint frequency
2 = Torque current limit (P112)
3 = Actual frequency PID
4 = Frequency addition
5 = Frequency subtraction
6 = Current limit (not SK 300E)
7 = Maximum frequency (not SK 300E)
8 = Actual PID frequency limited
9 = Actual PID frequency monitored
10 = Torque (not SK 300E)
11 = Torque lead (not SK 300E)
12 = Control terminals POSICON (not

SK 300E)

13 = Multiplication (not SK 300E)
14 = PI process controller actual value

15 = PI process controller setpoint
16 = PI process controller lead
17 = Digital In bits 0...7
18 = Curve travel calculator (not SK 300E)
19 = Set relay
20 = Set analog output
21 = Setpoint position Low word

(SK 530E and above)

22 = Setpoint position High word

(SK 530E and above)

23 = Setpoint position increment Low word

(SK 530E and above)

24 = Setpoint position increment High word

(SK 530E and above)

25 = ... 45 reserved

46 = Setpoint, torque process controller

(not SK 300E)

47 = Gearing transfer factor (only SK 500E)

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Parameter

Setting value / Description / Note

Comments

P548 (P)

Function Bus setpoint 3

(Function of bus setpoint 3)

except SK 54xE

0 ... 46 (47)
{ 0 }

In this parameter, a function is assigned to the delivered setpoint 3 (SW3) for bus control. This is
only available if P546  3 (only applies for SK 700E / SK 750E).

For setting values, see parameter (P547)

NOTE

As of firmware version V1.9 R0 for the SK 500E series, not only current error messages but
also warnings and information messages can be displayed via the parameter. In this context,
the parameter (P700) has been converted into an array parameter. I.e. error messages are
displayed in (P700 [-01]), warnings in (P700[-02]), and information in (P700 [-03]).

For all other series (SK 300E, SK 700E, SK 750E), parameter (P700) still only indicates error
messages.

Parameter

Setting value / Description / Note

Comments

P740 ... [-01]
…
... [-06]

Process data Bus In

(Process data Bus In)

SK 300E, SK 700E, SK 750E

0000 ... FFFF (hex)

Displays the actual control word and the setpoints.

[-01] = Control word
[-02] = Setpoint 1 (P546)
[-03] = Setpoint 1 High byte
[-04] = Setpoint 2 (P547)
[-05] = Setpoint 3 (P548)
[-06] = Bus I/O In Bits (P480)

P740 ... [-01]
…
... [-13]

Process data Bus In

(Process data Bus In)

SK 500E to SK 535E

0000 ... FFFF (hex)

This parameter informs about
the actual control word and
the setpoints that are
transferred via the bus
systems.

[-01 ] = Control word

Control word, source from
P509.

[-02] = Setpoint 1
[-03] = Setpoint 2
[-04] = Setpoint 3

Setpoint data from main
setpoint P510 - 01.

[-05] = Bus I/O In Bits (P480)

The displayed value depicts
all Bus In bit sources linked
with OR.

[-06] = Parameter data In 1
[-07] = Parameter data In 2
[-08] = Parameter data In 3
[-09] = Parameter data In 4
[-10] = Parameter data In 5

Data during parameter
transfer.

[-11] = Setpoint 1
[-12] = Setpoint 2
[-13] = Setpoint 3

Setpoint data from auxiliary
setpoint P510 - 02.

1.8.1.3 Information parameters

56 Subject to technical amendments BU 0050 GB-3111

1.8 USS – Frequency inverter settings

Parameter

Setting value / Description / Note

Comments

P740 ... [-01]
…
... [-23]

Process data Bus In

(Process data Bus In)

SK 540E / SK 545E

0000 ... FFFF (hex)

This parameter informs
about the actual control
word and the setpoints that
are transferred via the bus
systems.

For display, a BUS system
must be selected in P509

[-01 ] = Control word

Control word, source from
P509.

[-02] = Setpoint 1
[-03] = Setpoint 2
[-04] = Setpoint 3
[-05] = Setpoint 4
[-06] = Setpoint 5

Setpoint data from main
setpoint (P510 [-01]).

[-07] = Bus I/O In Bits (P480)

The displayed value depicts all
Bus In bit sources linked with
OR.

[-08] = Parameter data In 1
[-09] = Parameter data In 2
[-10] = Parameter data In 3
[-11] = Parameter data In 4
[-12] = Parameter data In 5

Data during parameter transfer:
Order label (AK), Parameter
number (PNU), Index (IND),
Parameter value (PWE 1/2)

[-13] = Setpoint 1
[-14] = Setpoint 2
[-15] = Setpoint 3
[-16] = Setpoint 4
[-17] = Setpoint 5

Setpoint data from the master
function value (Broadcast), if
P509 = 9/10
(P510 [-02])

[-18] = Control word PLC

Control word, source PLC

[-19] = Setpoint 1
[-20] = Setpoint 2
[-21] = Setpoint 3
[-22] = Setpoint 4
[-23] = Setpoint 5

Setpoint data from the PLC.

P741 ... [-01]
…
... [-06]

Process data Bus Out

(Process data Bus Out)

SK 300E, SK 700E, SK 750E

0000 ... FFFF (hex)

Displays the actual status word and actual values.

[-01] = Status word
[-02] = Actual value 1 (P543)
[-03] = Actual value 1 High byte
[-04] = Actual value 2 (P544)
[-05] = Actual value 3 (P545)
[-06] = Bus I/O Out Bits (P481)

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Parameter

Setting value / Description / Note

Comments

P741 ... [-01]
…
... [-13]

Process data Bus Out

(Process data Bus Out)

SK 500E to SK 535E

0000 ... FFFF (hex)

This parameter provides
information about the actual
status word and the actual
values that are transferred via
the bus systems.

[-01] = Status word

Status word, source from
P509.

[-02] = Actual value 1 (P543)
[-03] = Actual value 2 (P544)
[-04] = Actual value 3 (P545)

[-05] = Bus I/O Out Bit (P481)

The displayed value depicts
all Bus In bit sources linked
with OR.

[-06] = Parameter data Out 1
[-07] = Parameter data Out 2
[-08] = Parameter data Out 3
[-09] = Parameter data Out 4
[-10] = Parameter data Out 5

Data during parameter
transfer.

[-11] = Actual value 1 master
function
[-12] = Actual value 2 master
function
[-13] = Actual value 3 master
function

Actual value of master
function
502/P503.

P741 ... [-01]
…
... [-23]

Process data Bus Out

(Process data Bus Out)

SK 540E / SK 545E

0000 ... FFFF (hex)

This parameter provides
information about the actual
status word and the actual
values that are transferred via
the bus systems.

[-01] = Status word

Status word, source from
P509.

[-02] = Actual value 1 (P543 [-01])
[-03] = Actual value 2 (P543 [-02])
[-04] = Actual value 3 (P543 [-03])
[-05] = Actual value 4 (P543 [-04])
[-06] = Actual value 5 (P543 [-05])

[-07] = Bus I/O Out Bit (P481)

The displayed value
depicts all Bus In bit
sources linked with OR.

[-08] = Parameter data Out 1
[-09] = Parameter data Out 2
[-10] = Parameter data Out 3
[-11] = Parameter data Out 4
[-12] = Parameter data Out 5

Data during parameter
transfer.

[-13] = Actual value 1 master function
[-14] = Actual value 2 master function
[-15] = Actual value 3 master function
[-16] = Actual value 4 master function
[-17] = Actual value 5 master function

Actual value of master
function
502/P503.
[-18] = Status word PLC

Status word via PLC

[-19] = Actual value 1 PLC
[-20] = Actual value 2 PLC
[-21] = Actual value 3 PLC
[-22] = Actual value 4 PLC
[-23] = Actual value 5 PLC

Actual value data via PLC

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1.8 USS – Frequency inverter settings

Parameter

Setting value / Description / Note

Comments

P742

Database version

(Database version)

0 ... 9999

Displays the internal database version of the FI.

P744

Configuration level

(Configuration level)

SK 300E, SK 700E, SK 750E

0 ... 9999

This parameter displays the option modules detected by the FI.
The display with the ParameterBox is in plain text.
The possible combinations are displayed in code in the ControlBox. Both right digits indicate the

customer unit used and the two left digits indicate the special extension unit. The options vary
depending on the FI type.

Customer Unit SK CU1-…

Special extension unit SK XU1-...

No IO XX00
Basic IO XX01
Standard IO XX02
Multi IO XX03
USS IO XX04
CAN IO XX05
Profibus IO XX06

Encoder 01XX
POSICON 02XX

P744

Configuration level

(Configuration level)

SK 5xxE

0000 ... FFFF (hex)

This parameter displays the design status integrated in the FI. Display is in hexadecimal code
(SimpleBox, ControlBox, Bus system).

The display is in plain text when the ParameterBox is used.

SK 500E … 515E = 0000
SK 520E = 0101

SK 530E … 535E = 0201
SK 540E … 545E = 0301

P745

Module version

(Module version)

SK 300E, SK 5xxE

0.0 ... 3276.7

Design status (software version) of the technology unit (SK TU2/3-xxx), but only when a separate
processor is present, therefore not for SK TU2/3-CTR.

Have this data available if you have a technical query.

P745 ...[-01]
…
... [-03]

Module version

(Module version)

SK 700E, SK 750E

0.0 ... 3276.7

Software version of the installed module
[-01] Technology unit
[-02] Customer Unit
[-03] Special Extension Unit

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Parameter

Setting value / Description / Note

Comments

P746

Module status

(Module status)

SK 300E, SK 5xxE

0000 ... FFFF (hex)

Indicates the actual status (readiness, error, communication) of the technology unit (SK
TU2/3-xxx), but only when own processor is present, therefore not for the SK TU2/3-CTR.

Code details can be found in the respective BUS module manual. Different contents are shown
depending on the modules.

P746 ... [-01]
…
... [-03]

Module status

(Module status)

SK 700E, SK 750E

0000 ... FFFF (hex)

Status of integrated modules
[-01] Technology unit
[-02] Customer Unit
[-03] Special Extension Unit

NOTE

When activated, the functions block current, quick stop, remote control and cancel error
are available at the (local) control terminals. To operate the drive, a high signal must be present
on the digital inputs being used before the drive can be enabled.

60 Subject to technical amendments BU 0050 GB-3111

2.2 Modbus RTU - Features

2 Modbus RTU

(SK 540E and above)

2.1 The bus system

Modbus is an open communication protocol, which is based on a Master/Slave architecture. The bus system
must be set up in a linear configuration, whose ends are terminated with terminating resistors. In principle, up
to 256 participants are possible within a bus system. These communicate with each other via RS485.

2.2 Features

As standard, frequency inverters of version SK 540E and above provide the Modbus in version Modbus RTU
<8, E, 1>. Installation is by means of a two-core cable with an additional GND connection.

 Electrically isolated bus interface
 Modbus RTU <8, E, 1>
 up to 32 participants can be connected to a segment (communication via RS485)
 Point to point communication (between 2 participants) is possible via RS232
 Connection via terminal bar X7:73/74 (SK 520E and above) or
 connection via RJ12 socket (X11)

Caution: with more than 2 participants, communication via RS232 is not possible, and for their protection,
the RS232 contacts TXD and RXD must not be connected.

 Termination resistors can be connected via DIP switch on the FI (DIP 1).
 Address range 0,1,3 … 30

Address 2 must not be used!
Address 0 is reserved for the master (Broadcast Mode)

 The baud rate is adjustable (4800Baud … 38400Baud)

With communication between only 2 participants, an RS232 connection can be set up. In this case, care must
be taken that the communication speed may be lower, especially with long cable lengths.

For a network with more than 2 participants, the RS485 interface must always be used.
Switchover between the Modbus and the USS protocol is automatic. The condition for this is that address 2 is

not set in parameter (P512).

The frequency inverter can process 2 versions of the Modbus protocol.

1. Communication via Bus IOs: If the frequency inverter is to be accessed via Bus IO Bits, the functions
must be assigned in parameters (P480) and (P481). The source for the control word and the setpoints
(P509/P510) must be set to "Control terminals". (For details: see "Coil list")

2. Process data communication: If process data is to be exchanged or parameters changed, the source for
the control word and the setpoints (P509/P510) must be set to "USS". The definition of the parameters is
made in the parameters (P543) to (P548). (For details: see "Process data")

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NORD USS and Modbus RTU Manual

Function
Code

Function name

Description

01h

Read Coil

Reading access to all IN & OUT bits on the the bus

05h

Write Single Coils

Writing access to individual bus IN bits

0Fh

Write Multiple Coils

Simultaneous writing access to all bus IN bits

03h

Read Holding Register

Reading access to parameters

06h

Write Single Register

Writing access to an individual parameter (max 16Bit)

10h

Write Multiple Register

Writing access to 32Bit parameters or several PZD data

Address

8 bit

Function Codes

8 bit

Data

Variable = N x 8 bits

CRC

16 bit

2.3 Telegram Structure

The address field consists of eight Bits, which represent the address of the recipient. In its response, the Slave
returns this address to the Master, so that the master can identify the response. The function field consists of 8
Bits. These encode how the content of the data field is to be interpreted. If the Slave has received the query
from the Master correctly, it responds with the same function code. The structure of the data field is explained
in detail in the section "Function Codes". Finally, a 16Bit CRC checksum is transmitted.

2.4 RTU Frames

In RTU mode the start of transmission is not marked by control codes, but rather via a break in transmission at
least 3.5 characters long. The length of the transmission break therefore depends from the transfer speed. The
end of the message is also marked by a break in transmission which is at least 3.5 characters long.

2.5 Function Codes

Function codes specify the required action associated with the transmission of the telegram. The following
codes are supported:

62 Subject to technical amendments BU 0050 GB-3111

2.5 Modbus RTU: Function codes

Master  Slave

Slave  Master

Function Code

1 Byte

0x01

Function Code

1 Byte

0x01

Start address

2 Byte

0x0000 to 0x000F

Number of bytes

1 Byte

1 to 2

Number of bits

2 Byte

1 to 16

Status of bits

n Byte

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x01

Function Code

0x01

Start address High

0x00

Number of bytes

0x01

Start address Low

0x08

Status of Coils

0x03

Number of High Coils

0x00

CRC High

0x12

Number of Low Coils

0x04

CRC Low

0x15

CRC High

0xBC

CRC Low

0x92

Master  Slave

Slave  Master

Function Code

1 Byte

0x05

Function Code

1 Byte

0x05

Address

2 Byte

0x0000 to 0x0007

Address

2 Byte

0x0000 to 0x0007

Coil value

2 Byte

0x0000 or 0xFF00

Coil value

2 Byte

0x0000 or 0xFF00

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x05

Function Code

0x05

Address High

0x00

Address High

0x00

Address Low

0x01

Address Low

0x01

Coil value High

0xFF

Coil value High

0xFF

Coil value Low

0x00

Coil value Low

0x00

CRC High

0xDD

CRC High

0xDD

CRC Low

0x63

CRC Low

0x63

2.5.1 01h Read Coil

This function enables the readout of inverter bits. The addresses of the bits are listed in the "Coil List".

Example:

4 bits are queries from the address 0x0008 (Bus OUT bits 1 to 4). The bus OUT bits 1 and 2 are High and the
other two bits are Low.

2.5.2 05h Write Single Coils

Writes a single 1Bit value The addresses of the bits are listed in the Coil List.
The value 0x0000 is written if a bit is to be deleted. 0xFF00 is written if the bit is to be set.

Example:

Bus IN Bit 2 is set to the address 0x0001.

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Master  Slave

Slave  Master

Function Code

1 Byte

0x0F

Function Code

1 Byte

0x0F

Start address

2 Byte

0x0000 to 0x0007

Start address

2 Byte

0x0000 to 0x0007

Number of Coils

2 Byte

0x0001 to 0x0008

Number of Coils

2 Byte

0x0001 to 0x0008

Number of bytes

1 Byte

1

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x0F

Function Code

0x0F

Start address High

0x00

Start address High

0x00

Start address Low

0x01

Start address Low

0x01

Number of High Coils

0x00

Number of High Coils

0x00

Number of Low Coils

0x04

Number of Low Coils

0x04

Number of bytes

0x01

CRC High

0x05

Coil value

0x0D

CRC Low

0x51

CRC High

0x02

CRC Low

0xF9

2.5.3 0Fh Write Multiple Coils

Via this access, all of the 8 writable coils can be switched simultaneously.

Example:

Bus IN Bits 2, 4 and 5 are set from start address 0x0001.

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2.5 Modbus RTU: Function codes

NOTE

The parameter (P050) "Process data IN" and (P051) "Process data OUT" are executed in the
background and are not visible to the user. From a structural point of view, these are array
parameters ([-01 … -04]). Assignment of the setpoints in parameter (P050) is carried out via

the parameters (P546 (… P548)). The return of the actual values in parameter (P051) is

assigned in parameters (P543 (… P545)).

Master  Slave

Slave  Master

Function Code

1 Byte

0x03

Function Code

1 Byte

0x03

Start address

2 Byte

0x0000 to 0xFFFF

Number of bytes

2 Byte

0x01 to 0x08

Number of
parameters

2 Byte

0x0001 to 0x0004

Parameter value

N*2Byte

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x03

Function Code

0x03

Start address High

0x19

Number of bytes

0x02

Start address Low

0x80

Parameter value High

0x00

Number of parameters High

0x00

Parameter value Low

0xC8

Number of parameters Low

0x01

CRC High

0x65

CRC High

0x82

CRC Low

0xD3

CRC Low

0x27

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x03

Function Code

0x03

Start address High

0x0C

Number of bytes

0x08

Start address Low

0xC0

Parameter value 1 High

0x2B

Number of parameters High

0x00

Parameter value 1 Low

0x37

Number of parameters Low

0x04

Parameter value 2 High

0x09

CRC High

0x47

Parameter value 2 Low

0xC4

CRC Low

0xFC

Parameter value 3 High

0x02

Parameter value 3 Low

0x03

Parameter value 4 High

0x09

Parameter value 4 Low

0xC4

CRC High

0x65

CRC Low

0xD3

2.5.4 03h Read Holding Register

This enables the readout of one or more parameters. However, usually only a single 16Bit format parameter
can be read out. The function code 0x10 must be used for 32Bit parameters.

The only exception to this are the process parameters P050 and P051. Here, all the elements of the array
assigned to the parameter can be read out simultaneously.

Example 1:

Parameter P102, parameter set 1 is read out (Content = 200 / 0x00C8).

Example 2:

The following 4 process data are read out: status word and actual values 1 to 3 (P051[-00] to P051[-03]) status
word = 0x2B37 // IW1 = 0x09C4 // IW2 = 0x0203 // IW3 = 0x09C4.

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Master  Slave

Slave  Master

Function Code

1 Byte

0x06

Function Code

1 Byte

0x06

Address

2 Byte

0x0000 to 0xFFFF

Address

2 Byte

0x0000 to 0xFFFF

Parameter Value

2 Byte

0x0000 to 0xFFFF

Parameter Value

2 Byte

0x0000 to 0xFFFF

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x06

Function Code

0x06

Address High

0x19

Address High

0x19

Address Low

0x81

Address Low

0x81

Parameter value High

0x01

Parameter value High

0x01

Parameter value Low

0x23

Parameter value Low

0x23

CRC High

0x9E

CRC High

0x9E

CRC Low

0x6E

CRC Low

0x6E

NOTE

The parameter (P050) "Process data IN" and (P051) "Process data OUT" are executed in the
background and are not visible to the user. From a structural point of view, these are array
parameters ([-01 … -04]). Assignment of the setpoints in parameter (P050) is carried out via

the parameters (P546 (… P548)). The return of the actual values in parameter (P051) is
assigned in parameters (P543 (… P545)).

Master  Slave

Slave  Master

Function Code

1 Byte

0x10

Function Code

1 Byte

0x10

Start address

2 Byte

0x0000 to 0xFFFF

Start address

2 Byte

0x0000 to 0xFFFF

Number of
parameters

2 Byte

0x0001 to 0x0004

Number of parameters

2 Byte

0x0001 to 0x0004
Number of bytes

1 Byte

0x01 to 0x08

Parameter Value

N*2 Byte

2.5.5 06h Write Single Register

Enables writing of a single 16Bit parameter.

Example:

Parameter P102, parameter set 2 is written with the value 0x0123 (see also the item "Parameter access" in
Section 2.8 Description of parameters).

2.5.6 10h Write Multiple Register

This command enables several parameters to be written consecutively, and for parameters with a data length
of 32Bit.

In the process data area, all process data of the P050 parameter array can be written simultaneously.
If parameters are written with this access, only a single parameter can be written with a telegram. This access

is used to write 32Bit parameters.

66 Subject to technical amendments BU 0050 GB-3111

Example 1:

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x10

Function Code

0x10

Start address High

0x99

Start address High

0x99

Start address Low

0x40

Start address Low

0x40

Number of parameters High

0x00

Number of parameters High

0x00

Number of parameters Low

0x02

Number of parameters Low

0x02

Number of bytes

0x04

CRC High

0x6E

Parameter value 1 High

0x00

CRC Low

0x19

Parameter value 1 Low

0x12

Parameter value 2 High

0x34

Parameter value 2 Low

0x56

CRC High

0x29

CRC Low

0xAE

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x10

Function Code

0x10

Start address High

0x0C

Start address High

0x0C

Start address Low

0x81

Start address Low

0x81

Number of parameters High

0x00

Number of parameters High

0x00

Number of parameters Low

0x03

Number of parameters Low

0x03

Number of bytes

0x06

CRC High

0xD3

Parameter value 1 High

0x03

CRC Low

0xE9

Parameter value 1 Low

0xE8

Parameter value 2 High

0x07

Parameter value 2 Low

0xD0

Parameter value 3 High

0x0B

Parameter value 3 Low

0xB8

CRC High

0xF5

CRC Low

0xDF

Parameter P613 [0] is written with the value 0x00123456.

Example 2:

Parameters P050[1] to P050[3], i.e. setpoint values 1 to 3 are written.
Control word1 = 1000 // SW2 = 2000 // SW3 = 3000.

2.5 Modbus RTU: Function codes

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Slave  Master

Function Code

1 Byte

0x80 + Function code of the Master query

Exception Code

1 Byte

0x01 to 0x06

Exception Code

Description

01h

 A function code has been sent, which is not supported by the FI.

02h

 The telegram which has been sent is too long.
 For read queries, the data range to be read out is too large.
 The queried parameter is not known.
 The parameter sub-index is not known.

03h

 An incorrect data content has been transmitted in the function "Write Single Coil".
 The number of parameters is above the limit set by Modbus.

04h

 Error in access to the parameter database of the FI.
 The number of coils to be written in the function "Write Single Coil" has been

exceeded

06h

 The Slave is still occupied with current query and cannot receive a new order.

Query (Master  Slave)

Response (Slave  Master)

Address

0x08

Address

0x08

Function Code

0x06

Function Code

0x06

Address High

0x19

Address High

0x19

Address Low

0x81

Address Low

0x81

Parameter value High

0x01

Parameter value High

0x01

Parameter value Low

0x23

Parameter value Low

0x23

CRC High

0x9E

CRC High

0x9E

CRC Low

0x6E

CRC Low

0x6E

2.6 Exception Responses

If a query by the Modbus Master cannot be answered correctly, an error message is sent instead of the normal
response. The error message is structured as follows:

Example:

Parameter P102, parameter set 2 is written with the value 0x0123.

2.7 Watchdog

Modbus communication can be monitored via the parameter P513. Monitoring is started with the first valid
telegram. If the FI does not receive a new telegram within the time set in P513, error 10.0 is triggered in the FI.

68 Subject to technical amendments BU 0050 GB-3111

2.8 Description of parameters

Bus IO In Bits

Bus IO Out Bits

Coil number

Name

R/W

Coil number

Name

R/W

0000h

Bus IO In 1

R/W

0008h

Bus IO OUT 1

R

0001h

Bus IO In 2

R/W

0009h

Bus IO OUT 2

R

0002h

Bus IO In 3

R/W

000Ah

Bus IO OUT 3

R

0003h

Bus IO In 4

R/W

000Bh

Bus IO OUT 4

R

0004h

Bus IO In 5

R/W

000Ch

Bus IO OUT 5

R

0005h

Bus IO In 6

R/W

000Dh

Bus IO OUT 6

R

0006h

Bus IO In 7

R/W

000Eh

Bus IO OUT 7

R

0007h

Bus IO In 8

R/W

000Fh

Bus IO OUT 8

R

NOTE

The parameter (P050) "Process data IN" and (P051) "Process data OUT" are executed in the
background and are not visible to the user. From a structural point of view, these are array
parameters ([-01 … -04]). Assignment of the setpoints in parameter (P050) is carried out via

the parameters (P546 (… P548)). The return of the actual values in parameter (P051) is

assigned in parameters (P543 (… P545)).

Parameter
{factory setting}

Setting value / Description / Note

P050 [-01]

...
[-04]

Process data IN

(Process data In)

0000 ... FFFF (hex)
{ all 0 }

This parameter is an internal parameter,
which can neither be edited nor
displayed.. The assignment of the
setpoints is carried out via parameters
(P546) … (P548) (SK540E and above:
(P546[-01]) … (P546[-03])).

[-01 ] = Control
word

Control word, source from
P509.

[-02] = Setpoint 1
[-03] = Setpoint 2
[-04] = Setpoint 3

(P546) or (P546[-01])
(P547) or (P546[-02])
(P548) or (P546[-03])

Setpoint data from main
setpoint (P510 [-01]).

P051 [-01]

...
[-04]

Process data OUT

(Process data OUT)

0000 ... FFFF (hex)
{ all 0 }

This parameter is an internal parameter,
which can neither be edited nor
displayed.. The assignment of the actual
values is carried out via parameters
(P543) … (P545) (SK540E and above:
(P543[-01]) … (P543[-03])).

[-01] = Status word

Status word, source from P509.

[-02] = Actual
value 1
[-03] = Actual
value 2
[-04] = Actual
value 3

(P543) or (P543[-01])
(P544) or (P543[-02])
(P545) or (P543[-03])

2.8 Description of parameters

Coil List

Via the Coil List it is possible to obtain direct access to the Bus IN/OUT bits. In order for these bits to function,
they must be parameterised in parameter P480 and P481 and the control word and setpoint must be
parameterised to the setting "Control terminals" via P509/P510.

Process data

The process data is sent to the FI by means of parameter access. In order for this process data to function, the
setpoint source P509/P510 must be set to "USS".

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NORD USS and Modbus RTU Manual

Start address

Bit 15 – Bit 6

Bit 5 – Bit 0

Parameter number

Array Index

NOTE

The description of the inverter parameters can be found in the main manual for the frequency
inverter (BU0500). However, parameters related to bus communication can also be found in
Section 1.8 .

Parameter access

The FI parameters cannot be directly accessed via the functions 03h, 06h or 10h, as many FI parameters have
array elements. Therefore, the addresses for NORD parameters are according to the following model:

The lower 5 bits are available for the array elements, so that the maximum array size is 63. The parameter
values are shifted by 6 places.

Examples

 P102 Parameter set 1 = 0x1980
 P102 Parameter set 2 = 0x1981
 P510 Array element 2 = 0x7F81

70 Subject to technical amendments BU 0050 GB-3111

3 Faults

NOTE

As of firmware version V1.9 R0 for the SK 500E series, not only current error messages but
also warnings and information messages can be displayed via the parameter. In this context,
the parameter (P700) has been converted into an array parameter. I.e. error messages are
displayed in (P700 [-01]), warnings in (P700[-02]), and information in (P700 [-03]).

For all other series (SK 300E, SK 700E, SK 750E), parameter (P700) still only indicates error
messages.

3.1 Troubleshooting

The majority of frequency inverter functions and operating data are continuously monitored and simultaneously
compared with limiting values. If a deviation is detected, the inverter reacts with a warning or an error
message.

Basic information on this topic is contained in the manual for the basic equipment.
Errors cause the frequency inverters to switch off, in order to prevent a device fault.
The following options are available to reset a fault (acknowledge):

1. Switching the mains off and on again,

2. By an appropriately programmed digital input (P420 ... P425 = Function 12),

3. By switching of the “Enable” on the frequency inverter (if no digital input is programmed for

acknowledgement),

4. By Bus acknowledgement or

5. By P506, the automatic error acknowledgement.

Device LEDs: As delivered, with SK 300E series devices (except ATEX versions) and SK 500E (without

technology unit), 2 LEDs (green/red) are externally visible. These indicate the actual device
status.

The green LED indicates that the mains voltage is present and operational, while a flashing

code that increases in speed shows the degree of overload at the frequency inverter output.

Thered LED signals actual error by flashing with a frequency which corresponds to the

number code of the fault.

3 Faults

The following table shows all the faults which are attributable to bus operation. In the operating display of the
optional "ControlBox" only error E010 is displayed. A finer categorisation of errors can be obtained from the
information parameters P700 "Actual Faults" or P701 "Last Fault 1...5".

3.1.1 Error display

ControlBox / SimpleBox:The 4-digit, 7 segment display of these boxes indicates a fault with its number and

the prefix "E". If the cause of the error is no longer present, the error display flashes and the error can be
acknowledged with the OK key.

ParameterBox: The error messages are shown in plain text.

3.1.2 Error memory

The current error is saved in parameter P700 and the last five error messages are saved in parameter P701 [­01]…[-05]. Further information on inverter status at the time the error occurred are stored in parameters P702
to P706 / P799. More detailed information can be found in the main manual for the frequency inverter.

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NORD USS and Modbus RTU Manual

Display
in the ControlBox

Fault
Text in the ParameterBox

Cause

 Remedy

Group

Details in
P700 / P701

E010

10.0

(Bus Timeout)

Telegram timeout, data transfer is faulty. Check P513.

 Check external Bus connection.
 Check bus protocol program process.
 Check Bus Master.

10.2

Bus Timeout Option

Telegram timeout for external bus module,
telegram communication is faulty.

 Check external connection.
 Check bus protocol program process.
 Check Bus Master.

10.4

Init error Option

External bus module initialisation failure

 Check P746.
 Bus module not correctly plugged in.
 Check Bus module current supply.

10.1

System error option

External Bus module system failure

10.3

10.5

10.6

10.7

10.8

Error option

Communication error in external module
connection error/fault in external module

3.2 Error messages

Table of possible bus-specific error messages

72 Subject to technical amendments BU 0050 GB-3111

4 Additional information

NOTE

If possible, the reason for returning the component/device should be stated. If necessary, at
least one contact for queries should be stated.

This is important in order to keep repair times as short and efficient as possible.
On request you can obtain a suitable goods return voucher from Getriebebau NORD

GmbH.

4 Additional information

4.1 Maintenance and servicing information

In normal use, NORD frequency inverters and their accessories are maintenance-free.
If air intake filters have been built into the control cabinet, then these should also be regularly cleaned or

replaced.
If you contact our technical support, please have the precise device type (name plate/display), accessories

and/or options, the software version used (P707) and the series number (name plate) at hand.

Repairs

The device must be sent to the following address if it needs repairing:

NORD Electronic DRIVESYSTEMS GmbH

Tjüchkampstr. 37

26605 Aurich, Germany

For queries about repairs, please contact:

Getriebebau NORD GmbH & Co. KG

Tel.: 04532 / 401-515
Fax: 04532 / 401-555

If a frequency inverter or accessories are sent in for repair, no liability can be accepted for any added
components, e.g. such as line cables, potentiometer, external displays, etc.!

Please remove all non-original parts from the frequency inverter.

Internet information

You can also find the comprehensive manual in German and in English on our Internet site.

www.nord.com

4.2 Abbreviations in this manual

CU ....... Customer Unit (customer interface (internal)

DI, DIN . Digital input

EMC ..... Electromagnetic compatibility

FI ......... Frequency inverter

HW ....... Hardware

IND ....... Index

BU 0050 GB-3111 Subject to technical amendments 73

IW ..........Actual value

STW ......Control word

SW .......Software version, setpoint

TU .........Technology Unit (external)

ZSW ......Status word

NORD USS and Modbus RTU Manual

5 Keyword index

A

Actual bus value 1 (P543) ........... 56

Actual bus value 2 (P544) ........... 56

Actual bus value 3 (P545) ........... 56

Actual value ................................ 37

Assembly .................... 9, 13, 16, 18

Auxiliary bus setpoint (P510) ...... 53

B

Bus parameters ........................... 51

C

CE ................................................. 8

Configuration level (P744) .......... 63

Control word................................ 30

Control word source (P509) ........ 53

Customer Units ..................... 12, 18

D

Data transmission ....................... 26

Database version (P742) ........... 63

Displays and control .................... 75

E

EMC Directive ............................... 8

Error memory .............................. 75

F

H

Hyst. Bus IO Out Bits (P483)...... 51

I

Interface (P509) ......................... 53

L

Low Voltage Directive .................. 2

M

Master function output (P503) .... 52

Master function value (P502) ..... 52

Modbus RTU .............................. 65

01h Read Coil ................... 67

03h Read Holding Register 69

05h Write Single Coils ....... 67

06h Write Single Register .. 70

0Fh Write Multiple Coils ..... 68

10h Write Multiple Register 70

Coil List ............................ 73

Exception Code ................. 72

Features ........................... 65

Function codes.................. 66

Parameter access .............. 74

Process data ..................... 73

Telegram Structure ........... 66

PPO type (P507) ........................ 52

PPO types .................................. 27

Process Bus Out (P741) ....... 61, 62

Process data .............................. 29

Process data Bus In (P740) .. 59, 61

PZD ................................ ...... 26, 29

R

Repairs ....................................... 77

RoHS compliance ......................... 8

S

Safety information ........................ 2

Setpoint ...................................... 33

Setpoints source (P510) ............. 54

Settings ...................................... 51

SK 300E ..................................... 18

SK 500E ....................................... 9

SK 700E ..................................... 12

SK CU1-STD .............................. 14

SK CU1-USS .............................. 15

SK TU1-RS2 ............................... 13

Special extension units ............... 12

Stand. Bus IO Out Bits (P482) .... 51

Status machine ........................... 38

Status word ................................ 32

Structure of reference data ......... 26

Faults .......................................... 75

Function Bus IO In Bits (P480).... 51

Function Bus IO Out Bits (P481) . 51
Function Bus setpoint 1 (P546) ... 58
Function Bus setpoint 2 (P547) ... 58
Function Bus setpoint 3 (P548) ... 59

Function Bus setpoints (P546) .... 58

Module status(P746) .................. 64

Module version (P745) ............... 63

P

Parameter area .......................... 40

PKW ..................................... 26, 40

Posicon ...................................... 34

T

Technology Units ........................ 12

Telegram downtime (P513) ........ 55

U

USS address (P512) .................. 55

USS baud rate (P511) ................ 55

74 Subject to technical amendments BU 0050 GB-3111

5 Keyword index

BU 0050 GB 75

NORD USS and Modbus RTU Manual

Part. No. 607 0502 / 3111

76 Subject to technical amendments BU 0050 GB-3111