WL Trip Unit, MODBUS Communication
and Electronic Accessories Application
Guide
powerful ideas
WL Low Voltage Power
Circuit Breaker
ANSI / UL1066 & UL 489
Global network of innovation
Communication-capable Circuit Breakers
WL Circuit Breaker
Connection Diagram
Technological Leader Among Circuit Breakers: WL Communication
1 Breaker Data Adapter
(BDA)
2 Browser-capable input
and output device
(e.g. notebook)
3 WL Circuit Breaker
4 COM16 MODBUS
module or COM 15
PROFIBUS module
5 Breaker Status Sensor
(BSS)
6 Electronic Trip Unit
Metering function PLUS
7
8 Zone Selective
Interlocking (ZSI) module
9 Digital output module
with relay or optocoupler
outputs
10
Digital output module
with relay or optocoupler
outputs, remotely
configurable
11 Analog output module
Digital input module
12
13
WinPM.Net on PC
14 PLC (e.g. SIMATIC S7)
15 BDA Plus
13
14
2
1
13
9
10
8
4
5
6
7
* The Siemens BDA Plus or meters, 9330, 9350, 95/9600
can be used as a gateway to enable Ethernet communication
to the WL Circuit Breaker.
The 9500 meter can also be used as a central display unit
for multiple WL breakers with metering capability.
3
12
11
15
Communication-capable
Circuit Breaker
Introduction and Overview
WL Circuit Breaker
MODBUS Profile for WL Circuit Breaker
Breaker Data Adapter (BDA)
Breaker Data Adapter Plus (BDA Plus)
1
2
3
4
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
WL Circuit Breaker
Safety Guidelines
This manual contains notices which you should observe to ensure your own personal safety, as well as to
protect the product and connected equipment. These notices are highlighted in the manual by a warning
triangle and are marked as follows according to the level of danger. This equipment contains hazardous
voltages. Death, serious personal injury or property damage can result if safety instructions are not followed.
Only qualified personnel should work on or around this equipment after becoming thoroughly familiar with
all warnings, safety notices, and maintenance procedures contained herein. The successful
and safe operation of this equipment is dependent upon proper handling, installation, operation and
maintenance.
Danger
For the purpose of this manual and product labels, DANGER indicates an imminently hazardous situation
which, if not avoided, will result in death or serious injury.
Warning
For the purpose of this manual and product labels, WARNING indicates a potentially hazardous situation
which, if not avoided, could result in death or serious injury.
Caution
For the purpose of this manual and product labels, CAUTION indicates a potentially hazardous situation
which, if not avoided, may result in minor or moderate injury.
Attention
Draws your attention to particularly important information on the product, handling the product or to a
particular part of the documentation.
Qualified Personnel
For the purpose of this manual and product labels, a qualified person is one who is familiar with the
installation, construction and operation of the equipment, and the hazards involved. In addition, he or she
has the following qualifications:
(a) Is trained and authorized to energize, de-energize, clear, ground and tag circuits and equipment in
accordance with established safety practices.
(b) Is trained in the proper care and use of protective equipment, such as rubber gloves, hard hat, safety
glasses or face shield, flash clothing, etc., in accordance with established safety practices.
(c) Is trained in rendering first aid.
Correct Usage
Note the following:
Warning
This device and its components may only be used for the applications described in the catalog or
the technical descriptions, and only in connection with devices or components from other
manufacturers which have been approved or recommended by Siemens.
This product can only function correctly and safely if it is transported, stored, set up, and installed
correctly, and operated and maintained as recommended.
Registered Trademarks
WinPM.Net is a registered trademark of Siemens Energy & Automation. MODBUS® is a registered
trademark of MODICON. Some other designations used in these documents are also brands;
the owner's rights may be violated if they are used by third parties for their own purposes.
Excel and Explorer are registered trademarks of Microsoft Corporation. Java is a registered
trademark of Sun Microsystems. Netscape is a registered trademark of AOL Time Warner.
WL MODBUS Communication and Electronic Accessories • January 2005
Introduction and
Overview
Content of the Manual
Overview of the Bus Systems
Communicating with the Circuit Breaker
1
WL MODBUS Communication and Electronic Accessories • January 2005
Introduction and Overview
WL Circuit Breaker
General
This manual is aimed at those
who want to find out more
about the different applications
of communications-capable
circuit breakers in power
distribution systems.
It contains a detailed guide to
commissioning, operating,
diagnosing and maintaining the
new communications-capable
WL Circuit Breaker.
Content of the Manual
Chapter 1 contains a short
introduction to communications in
power distribution systems, and
provides an overview of the benefits
and applications of communicationscapable circuit breakers. The chapter
concludes with a short description of
the most important communication
bus systems.
Chapter 2 contains a general
description of the WL Circuit Breaker.
It includes information on
configuration data and provides
commissioning instructions.
Chapter 3 explains how the circuit
breakers are integrated in a power
management system and describes
the supported function codes,
register maps and exception codes.
WL is the first circuit breaker that
can be configured, diagnosed and
maintained remotely without the use
of field bus systems and higher-level
operator control and monitoring
systems. These procedures are carried
out using the breaker data adapter
(BDA), a state-of-the-art Internetcapable configuration device for
circuit breakers, which is described in
Chapter 4.
Introduction
The demand for communicationscapable systems, data transparency
and flexibility in industrial
automation systems is growing all
the time. Bus systems and intelligent
switchgear are vital to ensure that
industrial power systems can meet
these demands, since industrial
production and building
management are now inconceivable
without communications technology.
The evermore-stringent requirements
placed on the electrical and
mechanical aspects of circuit
breakers, the growing need for
flexibility and efficiency, and
increasing cost pressure and
automation have contributed to the
recent major innovations in circuit
breaker technology. In power
distribution systems, the WL Circuit
Breaker uses industry-standard bus
systems to transmit key information
for warnings, commissioning and
load shedding to a central control
room. The wide range of applications
ensure that these circuit breakers are
more than just simple switching and
protective devices.
Point-to-point communication, as
well as data entry, transmission,
analysis and visualization are only
possible if the automation and lowvoltage switchgear technology
components can be easily integrated
in a communication solution to
leverage the full range of functions
available.
1/1
WL MODBUS Communication and Electronic Accessories • January 2005
Introduction and Overview
WL Circuit Breaker
In this way, status information,
alarms, trip information and
setpoints (e.g. overcurrent, phase
unbalance, overvoltage) increase
transparency in power distribution
systems, enabling these situations
to be dealt with quickly. A
communication host can send
short text messages to the cell
phones of maintenance personnel.
Prompt analysis of this data enables
targeted intervention in the process
and helps reduce system down
time.
Information for preventive
maintenance (e.g. the number of
operating cycles or hours) enables
timely personnel and material
scheduling, which increases system
availability and helps prevent
sensitive system components from
being damaged.
Communication helps provide rapid
and targeted information on the
location and cause of power
failures. The cause of the fault can
be determined by recording the
phase currents (e.g. trip as a result
of a short-circuit of 2317 A in phase
L2 on 08/27/2002 at 14:27). This
information can be used to quickly
rectify the fault and reduces
downtime for quicker recovery.
Measuring and communicating
power, power factor and energy
allows an even greater number of
applications. The availibility of
power consumption data on a
targeted basis for business analysis
enables power profiles to be created
and costs to be clearly assigned. In
this way, energy costs can be
allocated and optimized by
balancing the peak loads.
WL Circuit Breakers—Modular and
Intelligent
Thousands of options with just a few
components: That's the WL. A new
generation of circuit breakers – from
200A to 5000A – with a modular
design to support every conceivable
application in power distribution
systems – cost effective and flexible,
its communication functionality
enables it to be integrated in
system solutions.
Cost Saving
Whatever the configuration, the WL
Circuit Breaker does the job where it
matters. Advantages include simple
retrofitting and a compact design
benefiting everyone who uses WL
Circuit Breakers, whether in
planning, business, or whether they
develop or operate switchgear
systems.
Easy Planning
The WL Circuit Breaker and EasyTCC
together provide a convenient
software package for coordinating
multiple circuit breakers.
System Solutions
By integrating WL Circuit Breakers in
a higher-level communication
system, they can be configured via
MODBUS, Ethernet or the Internet;
an integrated power management
system allows you to optimize
power distribution across the board.
Graphic
1-1
Graphic
1-2
Saving costs increases
productivity.
Simplified planning every
step of the way.
WL MODBUS Communication and Electronic Accessories • January 2005
System solutions - Supports
Graphic
energy management through
1-3
advanced metering and
communications.
1/2
Introduction and Overview
WL Circuit Breaker
Communication Bus Systems
Communication bus systems
are used to connect distribution
devices with varying levels of
intelligence. With their
different structures and
mechanisms, certain bus
systems are designed for highly
specific applications, while
others are better suited for
more open applications. The
following section describes the
most important bus systems
used in automation and power
distribution systems.
MODBUS
MODBUS is an open, serial
communications protocol based on a
master-slave architecture. Since it is
very easy to implement on any kind
of serial interface, it can be used in a
wide range of applications. MODBUS
comprises a master and several
slaves, whereby communication is
controlled exclusively by the master.
MODBUS features two basic
communication mechanisms:
• Question/answer (polling): The
master sends an inquiry to a station
and waits for a response.
• Broadcast: The master sends a
command to all the network
stations, which execute the
command without confirmation.
The messages enable process data
(input/output data) to be written to
and read from the slaves either
individually or in groups.
The data can either be transmitted in
ASCII or as a package in RTU format.
MODBUS can be used over a wide
range of transmission media,
normally, on an RS 485 physical bus,
a twisted, shielded two-wire cable
with terminating resistors.
The MODBUS protocol was originally
developed for networking control
systems, and is often used for
connecting input/output modules to
a central PLC. Due to the low
transmission rate of 38.4 kBaud
max., MODBUS is particularly
recommended for applications with a
low number of stations or low
response time requirements.
1/3
WL MODBUS Communication and Electronic Accessories • January 2005
Introduction and Overview
WL Circuit Breaker
Communication Structure of the
WL Circuit Breakers
The following diagram:
• Provides an overview of the
different communication options
available with WL Circuit Breakers
and their modules.
• Illustrates the high level of system
flexibility, enabling new and
innovative ideas to be
implemented.
Connection Diagram
1 Breaker Data Adapter
(BDA)
2 Browser-capable input
and output device
(e.g. notebook)
3 WL Circuit Breaker
4 COM16 MODBUS
module or COM 15
PROFIBUS module
5 Breaker Status Sensor
(BSS)
6 Electronic Trip Unit
7 Metering function PLUS
8 Zone Selective
Interlocking (ZSI) module
9
Digital output module
with relay or optocoupler
outputs
10
Digital output module
with relay or optocoupler
outputs, remotely
configurable
11
Analog output module
Digital input module
12
13
WinPM.Net on PC
14 PLC (e.g. SIMATIC S7)
15 BDA Plus
Starting at the lowest level with
simple configuration of the circuit
breakers, to the field level with
a PLC and WinPM.Net software
tool, to a connection to the
Intranet/Internet, the potential for
saving on power costs by means of
intelligent power management is
achieveable.
The individual circuit breakers and
their modules are described in the
following chapters.
13
14
2
1
* The Siemens BDA Plus or meters, 9330, 9350, 95/9600
can be used as a gateway to enable Ethernet communication
to the WL Circuit Breaker.
The 9500 meter can also be used as a central display unit
for multiple WL breakers with metering capability.
13
9
10
8
4
5
6
7
3
12
11
15
WL MODBUS Communication and Electronic Accessories • January 2005
1/4
Introduction and Overview
WL Circuit Breaker
Ethernet
The Industrial Ethernet is a highperformance network that conforms
to IEE 802.3 (ETHERNET). The highly
successful 10Mbit/s technology,
which has been used for over a
decade, and the new 100Mbit/s
technology (Fast Ethernet to IEEE
802.3u) in conjunction with
Switching Full Duplex and
Autosensing enable the required
network performance to be adapted
to different requirements. The
appropriate data rates are selected
as required because complete
compatibility enables the
technology to be implemented on
a step-by-step basis.
Used in 80% of networks, Ethernet
is currently the best of its kind in
LAN environments.
Ethernet does not function
according to a master-slave
principle. All the stations have equal
priority on the bus, which means
that any station can be the sender
or receiver. A sender can only send
on the bus if no other station is
sending at that time. This is due to
the fact that the stations are always
"listening in" to find out whether
any messages are being sent to
them or any senders are currently
active. If a sender has started
sending, it checks that the message
it has sent is not corrupt. If the
message is not changed, the send
operation continues.
If the sender detects that its data is
corrupt, another sender must have
already started sending data. In this
case, both senders abort their
respective send operations.
After a random time has elapsed,
the sender restarts the send
operation. This is known as
CSMA/CD and, as a "random" access
procedure, does not guarantee a
response within a certain time
frame. This largely depends on the
bus load, which means that realtime applications cannot yet be
implemented with Ethernet.
1/5
WL MODBUS Communication and Electronic Accessories • January 2005
WL Circuit Breaker
Short description of WL Circuit Breaker
The CubicleBUS
Communication Function of the Trip Units
The COM16 MODBUS Module
Metering and Metering Plus
Description of Important Functions/Parameters
for Communication
External CubicleBUS Modules
External Power Consumption of a WL Circuit Breaker
with CubicleBUS
2
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
WL Circuit Breaker
Introduction and Overview
The demands regarding
communications
capability, data
transparency, flexibility
and integration in power
distribution systems are
increasing all the time.
The WL Circuit Breaker
is a modular circuit
breaker that fulfills the
requirements of the
future today.
Brief Description of the
WL Circuit Breaker
Circuit breakers today are
no longer simply devices
for protecting plants,
transformers, generators
and motors. Many users
now require a complete
overview of the plant from
a central control room and
round-the-clock access to
all available information.
Modern power distribution
systems are characterized
by the methods used to
network circuit breakers—
both with each other and
other components. The
circuit breakers in the
WL Circuit Breaker family
have a lot to offer:
It is possible to carry out
analysis and maintenance
procedures remotely via
the Internet. Operating
staff can be given
immediate access to
information on system
status and alarms. This is
not just a vision of the
future, but reality.
The WL Circuit Breaker
covers the entire range
from 200A to 5000A. The
devices are available with
different interrupting
ratings, allowing shortcircuit currents of up to
00kA to be interrupted
2
reliably.
WL Circuit Breakers can be
adapted to different system
conditions, which means
that a rating plug can be
used to adapt each circuit
breaker to the appropriate
rated current. This ensures
that optimum protection is
provided, even if changes
have been made in the
system. The modules
(reference Graphic 2-1) can
be replaced without the
need for the transformer
to be changed.
Note: Installation instructions related to the communication modules
described in this section can be found in the individual instruction sheets
and/or Section 9 of the Operator's Manual
PC with WinPM.Net
WL Circuit Breaker configuration
and monitoring software
Graphic 2-1 The system architecture of the WL Circuit Breaker with CubicleBUS enables simultaneous communication via MODBUS
and BDA with a laptop or Ethernet/Intranet/Internet.
2/1
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
WL Circuit Breaker
The ability to change between two
different parameter sets is also
possible. This function is particularly
useful in the event of a power
failure when an automatic transfer
is made from utility to generator
power, a process which can
involve changing many of the trip
unit parameters.
A wide range of lock-out systems
are available to improve reliability
during critical processes. All
accessories, such as shunt trips,
motor operators and communication
components, can be installed
quickly and easily; this is made
easier because the accessories are
identical across the entire product
line. The commitment to reducing
the overall number of parts results
in fewer spares to be ordered and
lower inventory costs.
The heart of each circuit breaker is
the electronic trip unit (ETU).
Several versions are available to
adapt the protective, metering, and
alarm functions to the system
requirements: from simple overload
and short-circuit protection to trip
units that can be configured
remotely and which feature a wide
range of metering and alarm
functions.
All circuit breakers with ETU745,
ETU748, ETU755 and ETU776
trip units are communications
capable, and allow additional
components to be internally
networked via the CubicleBUS.
The circuit breaker is connected to
MODBUS via the RS485 interface
on the COM16 module.
The breaker data adapter (BDA)
(see Chapter 4) also supports
higher-level networking/
communication (Intranet/Internet).
The CubicleBUS
The CubicleBUS, which connects all
the intelligent components within
the WL Circuit Breaker and enables
additional external components to
be connected quickly and reliably,
forms the backbone of the modular
architecture of the WL. The
CubicleBUS is already integrated in
and connected to all assembled
circuit breakers with the ETU745,
ETU748, ETU755, and ETU776
trip units.
The high level of system modularity
enables communication functions
(e.g. metering function) to be
retrofitted at any time. A WL Circuit
Breaker that is not communications
capable can be upgraded (e.g. by
exchanging ETU72
with CubicleBUS) quickly and easily
on site. All CubicleBUS modules can
access the existing data of the
circuit breaker directly, thereby
ensuring rapid access to information
and speedy responses to events.
By connecting additional, external
modules to the CubicleBUS, costeffective solutions for
communicating data from other
devices in the cubicle can be
implemented.
5 for ETU745
Communications Capability of the
Electronic Trip Units (ETUs)
The electronic trip units ETU745,
ETU748, ETU755, and ETU776 are
all communications capable. The
CubicleBUS is connected to the
circuit breaker terminals X8.1(-) to
X8.4(+)
Different versions of
communications-capable trip units
are available.
The front of the ETU745 has rotary
switches for setting protective
parameters. These can be read via
the communication device. The
ETU745 can also be installed with
a four-line display for the measured
values.
The ETU755 does not have rotary
switches or a display. The protective
parameters can only be changed
via communications. This trip unit
with remote-only parameter setting
is for special application demands.
The ETU776 features a graphical
display with a clearly structured,
key-driven menu. This not only
enables operators to display
measured values, status
information, and maintenance
information, but also to read all the
existing parameters and make
password-protected changes.
WL MODBUS Communication and Electronic Accessories • January 2005
2/2
Communication-capable Circuit Breakers
WL Circuit Breaker
Functional overview of the trip unit system
Basic FunctionsETU725ETU727ETU745
I
n
Long-time overcurrent protection✔✔✔
Function can be switched ON/OFF–––
Setting range
Switch-selectable overload protection
2
t or
I
(
L
Setting range of time delay class
(seconds)10s, set at 6 x
Setting range of time delay
(seconds)––1, 2, 3, 4, 5
Thermal memory––✔ (via slide switch)
Phase loss sensitivityat
Neutral protection–✔✔
Function can be switched ON/OFF–✔ (via slide switch)✔ (via slide switch)
N
N-conductor setting range
Short-time delayed overcurrent protection ✔✔✔
Function can be switched ON/OFF––✔ (via rotary switch)
Setting range
Setting range of time delay
(seconds)0, 0.02 (M), 0.1,0, 0.02 (M), 0.1,0.02 (M), 0.1, 0.2,
(
Setting range of time delay
(seconds)––0.1, 0.2, 0.3, 0.4
Zone Selective Interlocking (ZSI) function––per CubicleBUS module
Instantaneous overcurrent protection✔✔✔
Function can be switched ON/OFF,
Extended Instantaneous Protection
I
is enabled when OFF––✔ (via rotary switch)
Setting range
Ground fault protection–✔ (standard)
Trip and alarm function––✔
Detection of the ground fault current
by residual summing method–✔✔
Detection of the ground fault current
by direct sensing method––✔
Setting range of the
G
Setting range of the
Setting range of the time delay
(seconds)–0.1, 0.2, 0.3, 0.4, 0.50.1, 0.2, 0.3, 0.4, 0.5
Switch-selectable
ground fault protection
I2t
/ fixed)––✔
(
Setting range time delay
ZSI ground function––per CubicleBUS module
Extended Instantaneous Protection (EIP) allows the WL breaker to be applied at the withstand rating
of the breaker with minus 0% tolerance; that means no instantaneous override whatsoever. EIP further
enables the circuit breaker to be applied up to the full instantaneous rating of the breaker on systems
where the available fault current exceeds the withstand rating.
2
Ground Fault Module cannot be removed after installation.
WL MODBUS Communication and Electronic Accessories • January 2005
✔ available
– not available
O optional
Communication-capable Circuit Breakers
WL Circuit Breaker
Basic FunctionsETU725ETU727ETU745
Parameter sets
Selectable between
parameter set A and B–––
LCD
LCD, alphanumeric (4-line)––
LCD, graphic–––
Communication
CubicleBUS integrated––✔
Communication capability via
MODBUS or PROFIBUS––✔
Metering function
Metering function capability with
Metering Function PLUS––✔
Display by LED
Trip unit active✔✔✔
Alarm✔✔✔
ETU error✔✔✔
L trip✔✔✔
S trip✔✔✔
I trip✔✔✔
N trip–✔✔
G trip–✔✔
G alarm––✔ (only with ground fault module)
Tripped by extended protection or
protective relay function––✔
Communication––✔
Signal contacts with external CubicleBUS modules
(Opto or relay)
Overcurrent warning––✔
Load shedding ON/OFF––✔
Early signal of long-time trip (200 ms)––✔
Temperature alarm––✔
Phase unbalance––✔
Instantaneous trip––✔
Short-time trip––✔
Long-time trip––✔
Neutral conductor trip––✔
Ground fault protection trip––✔
Ground fault alarm––✔ (only with ground fault module)
Auxiliary relay––✔
ETU error––✔
O
(only with ground fault module)
(only with ground fault module)
Step for Settings via Communications or ETU Key Pad
Extended Instantaneous Protection (EIP) allows the WL breaker to be applied at the withstand rating of
the breaker with minus 0% tolerance; that means no instantaneous override whatsoever. EIP further
enables the circuit breaker to be applied up to the full instantaneous rating of the breaker on systems
where the available fault current exceeds the withstand rating.
2
Ground Fault Module cannot be removed after installation.
✔ available
– not available
O optional
Notes:
M = Indicates phase loss sensitivity is enabled. LT pickup reduced 80% when phase unbalance > 50%. ST delay = 20ms
Communications = Setting the parameters of the trip unit via the Breaker Data Adapter, MODBUS, or PROFIBUS
Key pad = Direct input at the trip unit
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
WL Circuit Breaker
Basic FunctionsETU748ETU755ETU776
Parameter sets
Selectable between
parameter set A and B–✔✔
LCD
LCD, alphanumeric (4-line)
LCD, graphic––✔
Communication
CubicleBUS integrated✔✔✔
Communication capability via
MODBUS or PROFIBUS✔✔ ✔
Metering function
Metering function capability with
Metering Function PLUS✔✔✔
Display by LED
Trip unit active✔✔✔
Alarm✔✔✔
ETU error✔✔✔
L trip✔✔✔
S trip✔✔✔
I trip-✔✔
N trip✔✔✔
G trip✔
G alarm✔ (only with ground fault module) ✔ (only with ground fault module) ✔ (only with ground fault module)
Tripped by extended protection or
protective relay function✔✔ ✔
Communication✔✔✔
Signal contacts with external CubicleBUS modules
(Opto or relay)
Overcurrent warning✔✔✔
Load shedding ON/OFF✔✔✔
Early signal of long-time trip (200 ms)✔✔✔
Temperature alarm✔✔✔
Phase unbalance✔✔ ✔
Instantaneous trip✔✔✔
Short-time trip✔✔✔
Long-time trip✔✔✔
Neutral conductor trip✔✔✔
Ground fault protection trip✔
Ground fault alarm✔ (only with ground fault module) ✔ (only with ground fault module) ✔ (only with ground fault module)
Auxiliary relay✔✔ ✔
ETU error✔✔✔
O––
(only with ground fault module) ✔ (only with ground fault module) ✔ (only with ground fault module)
(only with ground fault module) ✔ (only with ground fault module) ✔ (only with ground fault module)
WL MODBUS Communication and Electronic Accessories • January 2005
✔ available
– not available
O optional
2/6
Communication-capable Circuit Breakers
WL Circuit Breaker
Data Availability on the CubicleBUS
All modules connected to the CubicleBUS can request data
from other modules via the bus and generate data
themselves that can be read by other modules.
Each data point in the comprehensive WL Circuit Breaker
data dictionary can only be generated by a single
module—the data source. If this data source (module)
exists, the data points assigned to it also exist.
This information is described and communicated in the
If a data source (module) does not exist, the data point
does not exist either.
Again, the relevant property byte contains this
information.
The following table provides an overview of the internal
CubicleBUS modules and the data point groups (collection
of several data points) assigned to them.
See Chapter 3 Register List for a detailed description of
the individual data points.
property bytes.
CubicleBUS Modules
Data point groupETU745, 748, BSSCOM16Metering
Data points with the same source755 or 776Function
Protection parameter set A✓
Protection parameter set B (N/A for ETU745 or 748)✓
Extended protection parameters✓
Parameter for setpoints✓
MODBUS communication parameters✓
Parameters for metering settings✓
Device identification data✓✓
Circuit breaker position specifications✓
Status info. (circuit breaker open/closed, storage spring, etc.)✓
Alarms✓
Trip log✓✓
Setpoint messages✓
Maintenance information✓✓
Circuit breaker temperature✓
Temperature in the cubicle✓
3-phase currents✓
Current in neutral, ground-fault current; equip. spec.✓
3-phase voltage✓
Power KW, KVAR, KVA✓
Power factor✓
Frequency, total harm. distortion, form factor, crest factor✓
Harmonic analysis✓
Waveform buffer✓
Event log✓
System time✓
Plus
Table 2-2 The table shows which data points from the data dictionary are generated by which CubicleBUS module,
enabling you to quickly find out which modules are required for which system.
2/7
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
The MODBUS COM16 Module and the BSS
The COM16 module enables the
WL Circuit Breaker to exchange
data via MODBUS to supervisory
systems and MODBUS masters.
The COM16 module retrieves
some of the key data on the
status of the circuit breaker
(circuit breaker open/closed,
closing spring charged, ready-to-
close, etc.) via the CubicleBUS
from the BSS (breaker status
sensor). Both modules are,
therefore, offered together as
a MODBUS communication
package.
MODBUS Module COM16
The COM16 module for the WL
enables the circuit breaker to be
connected to any MODBUS master
network. This makes it easy to add
WL and a COM16 to existing
MODBUS networks.
If required, control/write access to
the circuit breaker can be locked
using hardware and software to
prevent any switching operations
taking place via MODBUS (manual
or automatic operation) or
parameters from being changed.
All key events are assigned a time
stamp from the integrated clock to
enable operators to keep track of
alarms. This device clock can be
synchronized with the clock in the
automation system.
A temperature sensor integrated in
the COM16 module measures the
temperature surrounding the
breaker in the switchgear cubicle.
Three integrated microswitches
located in the COM16 module are
used to detect the position of the
circuit breaker (connect, test,
disconnect and not present) and
communicate via MODBUS. The
circuit breaker can be remotely
operated only in the test or
connect position.
Pin Configuration
The COM16 module is connected to
the auxiliary conductor plug-in
system at X7.
The electrical connections to the
circuit breaker and the CubicleBUS
connection to the internal
CubicleBUS modules (ETU, BSS,
metering function, etc.) are defined
in Section 9 of the Operator's
Manual and the individual
instruction sheets.
WL Circuit Breaker
Interposing relays must be used if
the opening and closing solenoids
are designed for voltages other than
24V DC.
Terminals X9.1 and X9.2 must be
used if the second shunt trip rather
than the first shunt trip is used to
open the circuit breaker via
communication.
The unassigned user output can be
used as required and must be
connected in the same way as a
coupling device (see Graphic 2-4).
It can be used, for example, to reset
the trip indicator if the remote reset
option has been installed. As with
Open and Close, only voltages of up
to 24V DC are permitted (note the
polarity); coupling devices must be
used for higher voltages.
The communications line is
connected to the 9-pin interface on
the front of the COM16 module.
The CubicleBUS connection for a
RJ45 plug is located at the rear and
is used to connect the external
CubicleBUS modules. If no external
CubicleBUS module is connected,
the terminating resistor supplied
must be used as an RJ45 plug.
The unassigned user input can be
connected using a contact element
with the 24V DC from pin 1 to
transmit the status of the contact
element.
Graphic 2-2 The text on the COM16 module shows the external pin
configuration for connecting the closing solenoid and the shunt trips, as well as
the MODBUS write protection function and the unassigned input/output.
WL MODBUS Communication and Electronic Accessories • January 2005
2/8
Communication-capable Circuit Breakers
WL Circuit Breaker
MODBUS Write Protection (DPWriteEnable)
Write access via communications can be blocked either
temporarily or permanently.
The COM16 module features a hardware input for this
purpose. Pin 1 provides the 24V DC supply, which can
be connected to pin 2.
If this input is not bridged, write access and control is
disabled.
The following actions are blocked if the input of the
write-protect function has not been enabled:
• Breaker open/close
• Reset the last trip
• Change the protective parameters
• Change the parameters for the extended protection
function (metering function)
• Change the communication parameters
• Settings of the metering options
• Reset maintenance information (counters)
• Force the digital outputs from WinPM.Net
The following control functions are available even if
the write protection function has not been enabled:
• Change and set the trigger functions for the
waveform buffer
• Read the content of the waveform buffer
• Change the setpoint parameters
• Set/change the system time
• Change the free texts (comments, system IDs)
• Reset the min./max. values
• Change the unassigned user output
Graphic
2-3
This diagram illustrates how to wire the COM16 module if MODBUS is to
be used to switch the device open and closed. This diagram only applies
to 24V DC control voltage.
MODBUS Installation Guideline
The COM16 must be assembled and connected
as described in the WL Operating Instructions.
Of particular importance is the requirement to
ground the shield of the MODBUS cable.
2/9
Graphic
Interposing relays are required if a control voltage different than 24V DC
is used. If the 1st shunt trip is not used to switch off the device, use
2-4
terminals X9.1 and X9.2 to utilize the 2nd shunt trip.
WL MODBUS Communication and Electronic Accessories • January 2005
The write-protect function ensures that all the
required information can be transmitted, but
prevents any changes to the status of the circuit
breaker. Changes can then only be made locally.
Why does the write protection function permit
certain actions?
All actions that are not blocked are for remote
analysis only and do not have any effect on the
current status.
Data Exchange via the COM16 Module
When the COM16 module is configured to
exchange data, it is important to note that it is
shipped as standard with MODBUS address 126.
This can be changed during system configuration
(e.g. with the BDA, WinPM.Net, WL Config
software or ETU776 display).
The COM16 module has two LEDs (MODBUS and
CubicleBUS) for diagnostic purposes. These
indicate the operating status of the
communication line and the CubicleBUS networks.
Two LEDs are used to determine whether a
CubicleBUS module in the circuit breaker is
operational. First, the "COMM" LED on the trip
unit must be green, that is, the trip unit has
recognized at least one other CubicleBUS module.
At a minimum, this would only be the Metering
Function PLUS if the CubicleBUS was then
interrupted. Second, the CubicleBUS LED on the
COM16 module must be taken into account. If
this is lit with a steady green light, a connection
exists from the COM16 module to at least the
metering function Plus module.
If both LEDs are green (steady light for CubicleBUS
on the COM16 module and COMM on the trip
unit), communication is fully established between
the trip unit and the COM16 module.
Data is exchanged according to the following
principle: an up-to-date copy of all WL Circuit
Breaker data (apart from the waveform buffer) is
always stored in the COM16 module. A response
to a data query from the COM16 module to the
supervisory system can, be typically transmitted
in just a few milliseconds. Write data from the
supervisory system is forwarded to the
appropriate addressee on the CubicleBUS.
Communication-capable Circuit Breakers
WL Circuit Breaker
Figure
Graphic
Meaning Position and text on the cable
CubicleBUS - X7.1
CubicleBUS + X7.2
24V DC + X7.3
24V DC ground X7.4
Table 2-3 The 4 black cables from the COM16 module must be connected to
terminal strip X7, which is used to connect the COM16 module to the modules on
the CubicleBUS in the circuit breaker.
Front view of the MODBUS module for the WL Circuit Breaker with the
MODBUS connection and the two LEDs. The figure below shows a section
2-1
of the ETU745 and its LEDs for displaying status.
Rear view of the COM16 module. The RJ45 connection for the external
CubicleBUS modules can be clearly seen here. If no external CubicleBUS module
2-2
is connected, the bus must be terminated with the terminating resistor.
WL MODBUS Communication and Electronic Accessories • January 2005
2/10
Communication-capable Circuit Breakers
WL Circuit Breaker
MODBUS LED Meaning
Off No voltage on the COM16 module
RedBus error
Communication not possible
No communication with class 1 master
Green MODBUS communication OK
Cyclic data transmission with class 1 master
Table 2-4 The MODBUS LED provides information on the state of MODBUS communication in the
COM16 module.
CubicleBUS LEDMeaning
Off No CubicleBUS modules found
Red CubicleBUS error
Green flashing CubicleBUS module found, but no metering
function Plus or trip unit
Steady green lightCubicleBUS module found and connection
with the metering function Plus and/or
trip unit
Table 2-5 The CubicleBUS LED provides information on the state of CubicleBUS communication in
the COM16 module.
PositionRearMiddleFront
microswitchmicroswitchmicroswitch
(S46)(S47)(S48)
Connect position 1 0 0
Test position 0 1 0
Disconnect position 0 0 1
Circuit breaker fully withdrawn 0 0 0
Table 2-6 The COM16 module has 3 microswitches for determining the position of the circuit
breaker in the guide frame. Depending on which switch is actuated, the position described above
is communicated via the comm. system (1=contact closed, 0=contact open).
When the circuit breaker is fully
withdrawn, no further microswitches
are actuated. "Circuit breaker fully
withdrawn" is communicated
immediately.
The sequence described above
provides hysterisis for communicating
contact position and avoids
intermittent contact postitions
from being communicated.
With UL 489 fixed-mounted circuit
breakers, a heel plate is screwed to
the COM16 module to transmit
operating position.
The COM16 module features a builtin temperature sensor, which is
installed outside the circuit breaker,
and measures the temperature
surrounding the breaker.
It also contains a clock that provides
a time stamp for all events, such as
minimum and maximum measured
values, as well as warnings and trips.
Three microswitches located in the
COM16 module can determine the
position of a drawout circuit breaker
in the guide frame, which is then
communicated via the COM16
module. The positions are defined in
Table 2-6. When the position of the
circuit breaker has changed, the
microswitch that has been actuated
is opened before the next microswitch
is actuated. No microswitches are
actuated if the breaker is between
two of the three positions. The
previous state is communicated until
a new position is reached when the
circuit breaker is moved (see Table 2-6).
2/11
There is no way of determining the
direction in which the circuit breaker
is being moved once the "disconnect
position" microswitch has been
opened.
When the circuit breaker is initially
racked in, the next microswitch to be
actuated is the "test position." The
COM16 module communicates
"circuit breaker not present" until the
"test position" key is actuated. The
new event message is delayed by 10
seconds to ensure that the breaker is
firmly seated.
WL MODBUS Communication and Electronic Accessories • January 2005
Communication-capable Circuit Breakers
WL Circuit Breaker
Breaker Status Sensor (BSS)
BSS stands for "breaker status
sensor." All microswitches that
contain information on the state of
the circuit breaker are either
installed directly to the BSS or
connected to it. The BSS makes this
digital information available on the
CubicleBUS.
If the status of the circuit breaker in
the switchgear is to be displayed or
read via communications, the BSS
module and the appropriate
signaling switch must be installed
(if they are not already). The circuit
breaker must be installed with an
electronic trip unit of type ETU745
or higher.
The BSS can also be field installed.
The BSS indicates the following
information:
• Closing spring
(charged/discharged)
• Position of the main contacts
(open/closed)
• Ready-to-close signal
• Bell Alarm switch on the trip unit
(connected to the red mechanical
trip indicator)
• Signaling switch on the first
shunt trip
• Signaling switch on the second
shunt trip
The BSS is included when you order
the communications option with
with the assembled circuit breaker.
If a BSS is required without
communication (e.g. for operating
the BDA), it can be ordered
seperately.
Figure
This picture shows the BSS signaling contacts and how they have to be connected.
The BSS is factory installed when the communications option is ordered with the
2-3
assembled breaker.
WL MODBUS Communication and Electronic Accessories • January 2005
2/12
Communication-capable Circuit Breakers
WL Circuit Breaker
Metering Function Plus
The integrated metering function
can be used with all trip units
with a CubicleBUS connection. It
not only extends the range of
protection functions of the trip
unit but also provides additional
warnings and diagnostic options.
With its comprehensive range of
measured values, the integrated
WL Circuit Breaker metering
function is an excellent
alternative to external multi-
function metering devices.
General
In addition to the current values
supplied by the trip unit, the
metering function provides the
measured values in the power
distribution system required for
Power Management (voltage, power,
etc.). With its extended protection
function (e.g. undervoltage), the
metering function also provides
further options for monitoring and
protecting the power distribution
system.
The option of generating warnings if
setpoints are exceeded, speeds up
response to system alerts. As a
result, the metering function can
significantly increase system up-time.
The metering function module is
installed on the back of the trip unit
(ETU), as shown in Fig. 2-4. The trip
unit and metering function module
exchange all current data via a highspeed synchronous interface. The
metering function module provides
all the connected modules (e.g. the
COM16 module or BDA) with the
parameters for the protective relay
functions, the setpoints, measured
value settings, and the measured
values via the CubicleBUS, so that
they can be processed further. Using
the two CubicleBUS connections,
the metering function module is
connected to the trip unit and either
the BSS or directly to X7.
The metering function can be
implemented in all circuit breakers
with ETU745, ETU755, ETU748 and
ETU776. If the Metering Function
PLUS module is ordered with the
assembled circuit breaker, it will
already be installed and ready for
operation. The metering function
can be retrofitted at any time if the
circuit breaker is equipped with one
of the trip units listed above. It is
simply screwed onto the trip unit and
the CubicleBUS lines are snapped in.
Note: If installed by the customer,
the metering function is not
calibrated with the trip unit;
therefore, the accuracy of the
specifications in Table 2-7 cannot
be guaranteed.
2/13
Figure
2-4
The Metering Function Plus is located on the back of the trip unit. When ordered as
part of an assembled breaker catalog number, it is already installed and ready for
operation.
WL MODBUS Communication and Electronic Accessories • January 2005
Metering Function Plus
The Metering Function Plus module
extends the range of metering
functions to include harmonic and
waveform analysis.
Harmonic analysis
The Metering Function Plus module
senses the current and voltage, saves
the measured values, and carries out a
fast Fourier transformation. The result is
the distribution of the harmonics (in %)
up to the 29th harmonic. The
calculated values are made available via
the CubicleBUS and can be displayed in
WinPM.Net and the BDA (see Chapters 3
and 4). They can also be saved as an
Excel-compatible *.csv file for
subsequent diagnosis. On the ETU776
trip unit, the measured and calculated
values can also be displayed.
The harmonic analysis enables not
only the quality of the network to be
analyzed and logged but also provides
settable alarm levels.
Waveform buffer
The Metering Function Plus module
features two independent waveform
buffers (A and B). Each one has 8
channels, one each for currents I
, IN, and Ig, and voltages Va, Vb, and
I
c
. Each channel is sensed with a
V
c
a
, Ib,
frequency of 1,649 kHz and the values
are "pushed" through a shift register
(length: 1 second). The process of
pushing data through the shift register
can be aborted by a configurable
trigger event. Trigger events include
trips, warnings and setpoint alarms
so that the voltage waveform, for
example, can be recorded in the
event of undervoltage tripping.
Figure
2-5
Communication-capable Circuit Breakers
WL Circuit Breaker
The Metering Function Plus analyzes the harmonics. This screenshot from the WinPM.Net
system shows how the analysis results are displayed.
Figure
WL MODBUS Communication and Electronic Accessories • January 2005
Metering Function PLUS can record the current waveform. This can be displayed and
exported using WinPM.Net. A value of trip current is shown here.
2-6
2/14
Communication-capable Circuit Breakers
WL Circuit Breaker
The trigger event can be set
individually for each waveform
buffer. The point at which the trigger
event is to take place in the
waveform buffer can also be defined.
This setting can be used to set the
ratio of the pre-event history to the
post-event history. If the pre-trigger
event history is to be analyzed, the
position can be set to 80%. When the
event occurs, 0.8 seconds of preevent history and 0.2 seconds of
post-event history are available in the
waveform buffer, and an existing
COM16 module adds a time stamp to
the trigger event.
Each waveform buffer stops
independently, depending on the
trigger event and can be activated
again once the analysis is complete.
A large amount of data (approx. 25
kByte for each waveform) can be
downloaded and analyzed using
WinPM.Net, the BDA and the ETU776
display. Depending on the option,
a range of zoom options and export
functions are available.
600:120 = 5:1
(ITI Part # 460-600 or 468-600)
VT Accuracy
Each Metering Module presents a
purely resistive (unity power factor)
load to the transformer. Assuming no
other devices connected to the VT, a
ITI type 486 VT can safely feed 10
metering modules and and still
maintain 0.6% accuracy assuming the
wiring from the VT to the individual
metering modules is twisted pair and
kept to a minimum length.
This data applies to ambient
temperatures from 30ºC to 50ºC and
a primary voltage from 80% to 120%
.
V
n
Maximum distance from voltage
transformer
The maximum distance between the
metering function and the voltage
transformer depends on the cable
size and the desired accuracy class.
For a 14AWG cable, the maximum
distance should not exceed 50 m for
class 0.5 and 100 m for class 3. In
areas with high EMC exposure,
shielded cable should be used.
Parameters for the settings of the
metering function
The trip unit settings which must be
made are:
1)VT Primary Voltage (240V, 480V,
600V)
2)VT Secondary Voltage (100V,
110V, 120V)
3) VT Connection (Wye / LG, Delta / LL)
The following tools and functions are
available if the parameters have to be
changed:
• WinPM.Net
• WL Config
• BDA/BDA Plus
• ETU776 display
Voltage Transformers
For isolation reasons, a voltage
transformer is used in conjunction
with the Metering Function Plus
module. This prevents voltage signals
of up to 1kV from reaching the ETU
directly via the auxiliary secondary
connections.
The metering module (“Metering
Function Plus”) can be set to expect
3W or 4W (LL/LG) connections and
will adjust the amplitude and phase
of the signal as necessary.
Three VTs must be used at all times.
All three VTs should be rated for the
nominal system L-L voltage (e.g.
480V) and may have either 100V,
110V or 120V secondary voltages.
The following ratios and suggested
and equivalent VTs can be used:
240:120 = 2:1
(ITI Part # 460-240 or 468-240)
480:120 = 4:1
(ITI Part # 460-480 or 468-480)
kW demand 3-phase active power kWD total13 ... 8000kW ± 3% (power factor > 0.6)
kVA demand kVA total 13 ... 8000kVA ± 2%
kVAR demand kVAR per phase13 ... 8000kVA ± 2%
kVAR demand total -24000 ... 24000kvar ± 4% (power factor > 0.6)
kWhr imported1 ... 10000MWh ± 2%
kWhr exported1 ... 10000MWh ± 2%
kVARh imported1 ... 10000Mvarh ± 4%
kVARh exported1 ... 10000Mvarh ± 4%
Frequency 15 ... 440 Hz ± 0.1 Hz
Total harmonic distortions for current and voltage 2 ... 100% ± 3% from the meas. range up to the 29th harmonic
Phase unbalance for current and voltage 2 ... 150% ± 1%
Table 2-7 The metering function provides a minimum and maximum measured value for each measured value specified above. If the metering
function is retrofitted by the customer, the accuracy of the values specified cannot be ensured, since it will not have been calibrated with the trip unit.
1. Accuracy is specified as follows: ± (x%) from the upper limit of effective range + 2 LSD (Least Significant Digit))
as shipped from the factory
Measurement conditions:
Frequency f = 60 Hz
Power factor cos = 1
Waveform Total harmonic distortion≤ 5%; symmetrical load
Power supply UL Listed 24V DC class 2
Warm-up period 2 hours
Relative air humidity Up to 90%
Ambient temperature 35°C ± 5°C
Metering range:
Current 0.2 ... 1.2 I
Voltage 0.8 ... 1.2 V
WL MODBUS Communication and Electronic Accessories • January 2005
nmax
nmax
2/16
Communication-capable Circuit Breakers
WL Circuit Breaker
The extended protective relay functions of the metering function can monitor the following criteria and initiate a trip
if values are exceeded.
Protective Relay Function ANSI Device NumberSetting range Possible delay
Current unbalance465 ... 50% 0 ...15 s
Total harmonic distortion - current 81THDC5 ... 50% 5 ...15 s
Voltage unbalance475 ... 50% 0 ...15 s
Undervoltage 27100 ... 1100V 0 ...15 s
Overvoltage 59200 ... 1200V 0 ...15 s
Total harmonic distortion - voltage 81THDV5 ... 50% 5 ...15 s
Direction of phase rotation 47N--
Active power in normal direction 3213 ... 4000kW 0 ...15 s
Active power in reverse direction 32R13 ... 4000kW 0 ...15 s
Under frequency 81U40 ... 70 Hz 0 ...15 s
Over frequency81O40 ... 70 Hz 0 ...15 s
Table 2-8 Additional trip criteria can be set using the extended protective relay functions. A delay time can be set to prevent transient events from
causing nuisance trips: the circuit breaker will not trip unless the condition is present for longer than the delay time.
The metering function supplies the following Alarm Setpoint Functions:
Alarm Function Setting range Possible delay
Over current 30 ... 10000A 0 ... 255 s
Over current - ground fault 30 ... 10000A 0 ... 255 s
Over current - N-conductor 30 ... 10000A 0 ... 255 s
Phase unbalance - current 5 ... 50% 0 ... 255 s
Demand - current 30 ... 10000A 0 ... 255 s
Total harmonic distortion - current 5 ... 50% 5 ... 255 s
Undervoltage 15 ... 1200V 0 ... 255 s
Overvoltage 200 ... 1200V 0 ... 255 s
Phase unbalance - voltage 5 ... 50% 0 ... 255 s
Total harmonic distortion - voltage 5 ... 50% 5 ... 255 s
Crest factor 1 ... 3,000 0 ... 255 s
Form factor 1 ... 3,000 0 ... 255 s
Active power in normal direction 13 ... 10000kW 0 ... 255 s
Active power in reverse direction 13 ... 10000kW 0 ... 255 s
Leading power factor 0 ... -0.99 0 ... 255 s
Lagging power factor 0 ... 0.99 0 ... 255 s
Demand - active power -10000 ... 10000kW 0 ... 255 s
Apparent power 13 ... 10000kVA 0 ... 255 s
Reactive power in normal direction 13 ... 10000kvar 0 ... 255 s
Reactive power in reverse direction 13 ... 10000kvar 0 ... 255 s
Demand - apparent power 13 ... 10000kVA 0 ... 255 s
Demand - reactive power 13 ... 10000kvar 0 ... 255 s
Underfrequency 40 ... 70 Hz 0 ... 255 s
Overfrequency 40 ... 70 Hz 0 ... 255 s
Table 2-9 Alarm and setpoint functions allow events to be generated when system conditions deviate from their nominal values. The generation of the
events can be delayed to prevent transient conditions from “chattering”. These alarms are communicated via
to close in the configurable output module and can freeze the waveform buffer in the metering function. Alarms are communicated to the COM16/15
where they can be transmitted to the master.
CubicleBUS and can cause output contacts
2/17
WL MODBUS Communication and Electronic Accessories • January 2005
Loading...
+ 64 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.