V2.0
Danger and warning!
This device can be installed only by professionals.
The manufacturer shall not be held responsible for any accident caused
by the failure to comply with the instructions in this manual.
Risks of electric shocks, burning, or explosion
z This device can be installed and maintained only by qualified people.
z Before operating the device, isolate the voltage input and power supply
and short-circuit the secondary windings of all current transformers.
z Put all mechanical parts, doors, or covers in their original positions before
energizing the device.
z Always supply the device with the correct working voltage during its
operation.
Failure to take these preventive measures could cause damage to
equipment or injuries to people
SPM33 Multifunctional power meter
Contents
1.General Information ......................................................................................
2. Order information ........................................................................................
3. Dimension and Installation .........................................................................
3.1 Dimension ........................................................................................... 3
3.2 Installation ........................................................................................... 3
4. Operation ......................................................................................................
4.1 Real-time measurement data structure ............................................... 4
4.2 The graphic display ............................................................................. 5
4.3 Status Inquiry ........................................................................... ......... 6
4.4 Key Description .................................................................... ............. 6
4.5 Parameter settings ............................................................... ............. 7
5. Measuring Capability . ...............................................................................
5.1 Real-time basic electrical parameters ............................................... 13
5.1.1 Voltage ................................................................................... 14
5.1.2 Current ................................................................................... 14
5.1.3 Frequency .............................................................................. 15
13
4
3
1
2
......
SPM33 Multifunctional power meter
5.2 Demand Parameters ......................................................................... 1
5.3 Energy parameters ............................................................................17
5.4 Harmonic parameters ........................................................................ 17
5.5 Unbalance parameters ...................................................................... 18
5.6 Alarm Setpoint ................................................................................... 18
5.6.1 Alarm action condition ............................................................ 20
5.6.2 Alarm Output .......................................................................... 21
6. Input/output Characteristics ....................................................................
6.1 Relay output ...................................................................................... 21
6.2 Status input ....................................................................................... 23
6.3 Dual Source kWh measurement ....................................................... 24
7. Technical Datasheet ..................................................................................
8. Communication protocol ..........................................................................
8.1. Introduction ...................................................................................... 27
8.2. Detailed Description of the SPM33 Modbus Protocol ....................... 28
8.2.1. SPM33 Modbus Protocol Rules ............................................ 28
8.2.2. Modes of Transmission ......................................................... 29
8.2.3. Description of the Modbus Packet Structure ......................... 29
27
25
21
5
SPM33 Multifunctional power meter
8.2.4. Abnormal Responses ............................................................ 31
8.2.5. Broadcast Packets ................................................................ 32
8.3. Packet Communication .................................................................... 33
8.3.1 Read the Relay Output Status (Function Code 01H) ............. 33
8.3.2. Read Holding Registers (Function Code 03H) ...................... 35
8.3.3 Relay Control (Function Code 05H) ....................................... 36
8.3.4. Preset Multiple Registers (Function code 10H) ..................... 37
8.4. Calculating the CRC-16 Error Check Field ....................................... 38
8.5. Description of SPM33 Registers....................................................... 42
8.6 Description of Data Types ................................................................. 42
8.6.1 Real-time data register list ..................................................... 43
8.6.2 List of demand data registers ................................................. 52
8.6.3 List of harmonic data registers ............................................... 55
8.6.4 List of configuration registers ................................................. 58
8.6.5 Register for command and clear energy ................................ 64
8.6.6 List of device information registers ........................................ 65
9. Maintenance and Trouble Shooting .........................................................
10. Appendix 1 ............................................................................................... 69
66
1. General Information
SPM33 three phase multi-function power meters, mainly apply to Low Voltage Distribution
System, which voltage below AC400V (L-N), it can through RS485/ Modbus communication
to manage instrument of network, and achieve automatic control.
The main characteristics of SPM33 are as follows:
Real-time parameter measurement
(Three-phase voltage, current, active power, reactive power, apparent power, power factor,
frequency, active energy, reactive energy, and other combined electrical parameters
measurement)
Demand measurement
(Phase current demand, sub-phase active demand, total active demand, the maximum
current demand, maximum total active demand, three phase reactive power, total reactive
power, three phase apparent power, total apparent power demand, save their maximum
value.)
2 active status in puts
2 relay outputs（optional）
Alarm function
Up to the 31
st
harmonic measurement, phase voltage and current harmonic content
(2 to 31),THD
1 RS485 communications, Modbus-RTU protocol
Phase sequence adjustment
Support Dual-source kWh measurement
1
2. Order information
SPM33 - □ - □
① ②
① ：Feature selection
R Two relay alarm output
② ：Rated identify measurement parameters
V1 3×220/380V, 5A
V2 3×220/ 380V ,1A
Example: SPM33-R-V1: the low-voltage three-phase multifunction power meter,
rated measuring 220/380V 5A, with standard 2 status inputs, optional 2 relay
alarm output.
2
3. Dimension and Installation
3.1 Dimension
unit：mm
3.2 Installation
unit：mm
3
COM ALARM
96.0
96.0
69.8
89.50
80.5
89.5
SPM33
9
0
.
0
+
0
.
5
-
0
.
0
9
0.0
+
0
.
5
-
0
.
0
4. Operation
4.1 Real-time measurement data structure
（1） Real-time measurement data display by the form of main menu、submenu：
page button of main menu： page button of submenu：
（2） Menu tree diagram:
① Can flip the main menu by press
.
② Can flip the submenu which under the main menu, by press
.
4
4.2 The graphic display
1 : Prompt of the currently displayed page；
2：Prompt display page number；
3：Status prompt of DI/DO ；
4：Data display area；
5：Energy display area；
6：The secondary menu prompt；
7：Prompt under a main menu；
Description:
(1) If there is no key operation within 60s, the backlight automatically turns off,
when the backlight is lit until the button operation again.
(2) Status prompt of DI/DO displays the current status of DI / DO ,each circle
represents a DI or DO signal, when DI signal or relay is closed, the
corresponding circle is solid; conversely, was hollow.
Phase U
1/8
I L-L
34379.7 kWh
A
B
C
kWh
V
V
V
2200
.
2200
.
2200
.
6
1
2
3
4
5
7
DO oo
DI oo
5
4.3 Status Inquiry
(1) COM lamp, always bright when power on, blinks when there is
communication.
(2) ALARM lamp, flashes when there is an alarm, off when no alarm off.
4.4 Key Description
Note: In a different interface, the same keys have different functions.
Sibling menu switch / move the cursor to the right
Switching sibling menu to submenu / move the cursor to the left
Exit
Enter the menu / confirm
6
4.5 Parameter settings
Meter Programming
SPM33 can program the following
parameters：
Project programming
CT values Adjustment
phase
sequence
Communication Language
Terminal Mode Demo
Alarm Password
Relay Version
Clean /
The projects of configuring different
instrument is not completely consistent,
not even, so the user should operate
according to the specific circumstances of
the instrument:
CT value：press key
to enter CT
interface，the figure as below.
You can set ratio according to the site CT,
CT setting range: 1 to 10000.
COM
ALARM
1/11
DI
oo
CT
1
COM
CT
SPM33
2. Communication: press key
to
enter the communication interface, can
set meter mailing address and baud rate,
the figure as below. Mailing Address
range: 1 to 247, the baud rate can be set:
4800, 9600, 19200
COM
ALARM
2/11
DI
oo
Addr
3
COM
Baud
4800
Mode
SPM33
3.Connection mode: press key
to
enter the interface, to set terminal
mode according to the scene of the
connection mode, figure as below.
Terminal mode can be set: three-phase
three-wire, three-phase four-wire;
7
COM
ALARM
3/11
DI
oo
Mode
4Y
Alarm
Mode
SPM33
4.Alarm：Press key
to enter the
voltage limit alarm interface, figure as
bellow:
COM
ALARM
4/11
DI
oo
Value
494.79
Relay U-lower
Alarm
Time
4
U-Upper
V
s
SPM33
Press key
，the user can view and
set the other object of alarm:
Voltage limit, current limit, lower limit of
current, frequency, frequency lower limit
and upper limit, alarm of phase lack, the
status 1 is broken.
① Action value of voltage upper limit：
unit is V，two decimal places.
Setting range: 110 ~ 500V.
Notice: action value of voltage upper limit
must be greater than voltage lower limit.
Can be set to”0”,”0”indicates that the
alarm type is closed.
②Action value of voltage lower limit :
unit is V，two decimal places.
Setting range: 110 ~ 500V.
Notice: action value of voltage lower limit
must be less than voltage upper limit. Can
be set to”0”,”0”indicates that the alarm
type is closed.
③Action value of current upper limit：
unit is A，one decimal places.
range：1.0~60000.0A.
Notice: current is the value for the upper
limit must be greater than current lower
limit. Can be set to”0”,”0”indicates that the
alarm type is closed.
8
④ Action value of current lower limit :
unit is A，one decimal places.
range：1.0~60000.0A.
Notice: current is the value for the primary
side. Action value of current lower limit
must be less than the current upper limit
can be set to “0”,”0”indicates that the
alarm type is closed.
⑤ Action value of frequency upper limit：
Unit is Hz，two decimal places.
range：45~65Hz.
Notice: action value of frequency upper
limit must be greater than frequency lower
limit. Can be set to”0”,”0”indicates that the
alarm type is closed.
⑥Action value of frequency lower limit：
Unit is Hz，two decimal places.
range：45~65Hz.
Notice: action value of frequency lower
limit must be less than frequency upper
limit. Can be set to “0”, ”0”indicates that
the alarm closed.
⑦Action value of power upper limit：
unit is kW，one decimal places.
range：0.1~40000.0kW.
Notice: power is the value for the primary
side. Can be set to”0”,”0”indicates that the
alarm
All of the above operation can set primary
side. Action value of current type is
closed.
the time of action，unit is s，
range：0~120s.
Notice: setting of voltage phase failure
and status 1 off：
On---said opening the alarm type;
Off---said closing the alarm type.
9
5. Relay: press key to enter the
relay 1 interface, figure as below.
Mode: You can set the remote or alarm
mode.
Reset time setting range: 0 ~ 120s.
COM
ALARM
5/11
DI
oo
Mode
Remote
Clear
Relay 1
Return
11
Relay 1
s
Relay 2
SPM33
Press key
，you can view the setting
of relay 2 ,it can set as the relay 1.
6. Clear: press key
to enter the
clear interface, figure as below. Can clear
energy or demand.
COM
ALARM
6/11
DI
oo
Energy
NO
Phase-Ad
Clear
Demand
NO
Clear
SPM33
7.Phase sequence adjustment: press the
keys
to enter the phase sequence
Adjust interface. figure as below，the user
can adjust the current channel phase
sequence and direction, which
corresponding to voltage ,in accordance
with the wiring on-site;
COM
ALARM
7/11
DI
oo
U1
Language
Phase-Ad
U1
U1
I1
I2
I3
SPM33
Voltage adjust current channel map, can
be set to:
I1： Channel voltage & I1 Channel current match,
-I1： Channel voltage & I1 Channel current
match,，I1 reversed polarity,
I2： Channel voltage & I2 Channel current
match,，
-I2： Channel voltage & I2 Channel current
match,I2 reversed polarity,
I3： Channel voltage & I3 Channel current
match,
-I3： Channel voltage & I3 Channel current
match,，I3 reversed polarity,
10
8. Language: press key to enter the
language setting interface, figure as
below, the user can choose Chinese and
English languages.
COM
ALARM
8/11
DI
oo
Language
English
DEMO
Language
SPM33
9.Demo：press key
to enter Demo
setting interface，figure as below.
OK：indicate open Demo mode
NO：indicate close Demo mode
COM
ALARM
9/11
DI
oo
Demo
NO
Password
Demo
SPM33
10. Password: press key
to enter
Password modification interface. figure as
below
11. Version: press key
to enter the
version display, figure as below, you can
view the software and hardware versions of
the instrument.
COM
ALARM
11/11
DI
oo
Soft
****
CT
Version
Hard
****
SPM33
11
Precautions
1.when password authentication input
password "33",the display the original
password;
2.when instrument work under the
three-phase three-wire mode , active
power, reactive power and power factor are
only the sum of the value, and there is no
concept of a single-phase, single-phase
value is 0;
3.For the instrument which do not
support the relay output function, will not
have the relevant settings menu;
4.When the data setting is invalid, the
set is unsuccessful, restore the original
parameters;
5. For other customization features, in this
description does not describe!
12
5. Measuring Capability
5.1 Real-time basic electrical parameters
SPM33 provides voltage, current, power, and frequency etc. basic parameters.
Real-time reading Measuring range
current
Each phase
0 ~ 65，000A
Zero sequence
0 ~ 65，000A
Degree of unbalance (%) 0 ~ 100%
voltage
Line-line 0 ~ 650V
Line-neutral line 0 ~ 400V
Degree of unbalance (%) 0 ~ 100%
Active power/Reactive power /Apparent power
Single phase 0 ~ ± 26MW/var/VA
Total 0 ~ ± 78MW/var/VA
Power factor
Single phase -1.000 ~ +1.000
To ta l - 1.0 00 ~ +1. 0 0 0
Frequency
35 ~ 65Hz 35 ~ 65Hz
13
5.1.1 Voltage
SPM33 maximum measurement of phase voltage is 400V, three-phase
three-wire line voltage can up to 500V. Users should be noted that during the
design of this, to prevent internal measuring circuit saturation, resulting in
inaccurate measurements. Wiring mode of voltage can be set by the panel or
communication, support “Y” and triangle connection mode.
Recommendation: After changing the wiring mode, you`d best clear energy,
re-accumulate energy.
5.1.2 Current
SPM33 must be conducted by CT to measure current. CT secondary rated
output required to meet the input requirements of SPM33 rated current (5A or
1A). When using an external CT, wiring should prevent open, otherwise it will
generate a higher voltage in the secondary role In the primary excitation effect,
causing no casualties or damage to equipment.
SPM33 overload of current measurement channel is generally 1.2 times the
rated current measurements. During the design of this users should be noted
that, to prevent internal measuring circuit saturation, resulting in inaccurate
measurements. SPM33 current measurement range: 0 ~ 65kA. Setting range of
CT transformation ratio is: 1 ~ 10000A.
14
5.1.3 Frequency
SPM33 working on different measurement mode, the acquisition channel of
the frequency measurement is not the same. In the triangle connection mode,
SPM33 measures frequency default by AB line voltage channel ; under other
modes, SPM33 measures the frequency by the A phase voltage channel. If
phase A default phase, then take the C phase. If A, C-phase default phase, then
take the B phase.
5.2 Demand Parameters
Demand refers to the value obtained in the following way: the accumulated
electrical parameters within a period of time divided by the time length. To
facilitate the operation of the user, SPM33 adopts the fixed-block calculation
method in the fixed period of time, and the period of time is fixed, being 15
minutes.
SPM33 provides the following demand data and measuring ranges:
15
Demand reading Measuring range
Demand current
Current every phase
0 ~ 65，000A
Maximum peak
0 ~ 65，000A
Active power
Every phase
Three-phase total
0 ~ ± 26MW
0 ~ ± 78MW
Maximum peak of every phase
Maximum peak of three-phase
total
0 ~ ± 26MW
0 ~ ± 78MW
Reactive power
Every phase
Three-phase total
0 ~ ± 26MVAR
0 ~ ± 78MVAR
Maximum peak of every phase
Maximum peak of three-phase
total
0 ~ ± 26MVAR
0 ~ ± 78MVAR
Apparent Power
Every phase
Three-phase total
0 ~ ± 26MVA
0 ~ ± 78MVA
Maximum peak of every phase
Maximum peak of three-phase
total
0 ~ ± 26MVA
0 ~ ± 78MVA
The figure below describes demand calculation:
16
5.3 Energy parameters
SPM33 input and output of active and reactive energy, the maximum cumulative
to 99,999,999.9, display one decimal place. When the accumulated value
reaches to maximum, it will overturn automatically.
5.4 Harmonic parameters
SPM33 provides optional measurement of complete 31st harmonic for voltage
and current as well as their total harmonic content (THD) .
The data of harmonics are given according to the percentage of fundamental
harmonics and have one digit after the decimal point. That is to say, when the
value of the fundamental harmonic is fixed at 1000, it is 100.0% of the effective
value of the fundamental harmonic; others are by analogy.
THD refers to the total of higher harmonics except fundamental harmonics, and
it is calculated according to the following formula:
∑
=
=
=
ni
i
i
X
THD
2
2
i
: Harmonic order.
i
X
: Percentage of the effective value of each harmonic to that of
the fundamental harmonic.
n
: Highest harmonic order, which should be 31 here.
【Attention】：Each harmonic and THD can be checked through display or
communication.
17
5.5 Unbalance parameters
SPM33 can measure current unbalance, the unbalance is calculated:
XmaxXmin-XmaxXunbal ）（=
×100％
Xunbal — The unbalance of the voltage or current
Xmax — Maximum value of the three-phase voltage or current
Xmin — Minimum value of the three-phase voltage or current
5.6 Alarm Setpoint
SPM33 with user definable valued system which can monitor the electrical
parameters of the instrument and set the action. When an alarm event occurs,
the instrument panel ALARM light will flash, meanwhile, the display can be
switched to the alarm interface to see the type of alarm events, or read the type
of alarm through communication, after the elimination of alarm events , ALARM
light will destroy , warning interface will appear as "no."
The object of the alarm type as below:
18
Object Alarm triggered remark
The upper
limit of voltage
maximum voltage value in three-phase
voltage> the voltage setting upper limit
(three-phase four-wire, voltage is phase
voltage; three-phase three-wire, voltage is
the line voltage)
the action value 0
indicates to close the
alarm object
The lower limit
of voltage
The minimum voltage value in
three-phase voltages which is greater
than 110V <the voltage setting lower
limit
(Three-phase four-wire, voltage is phase
voltage; three-phase three-wire, voltage is
the line voltage)
the action value 0
indicates to close the
alarm object
the upper limit
of current
The Max. primary current value in
three-phase current > the upper limit of
current setting value
the action value 0
indicates to close the
alarm object
the lower limit
of current
The Min. primary current value(nonzero)
in three-phase current > the lower limit of
current setting value
the action value 0
indicates to close the
alarm object
The upper
limit of
frequency
Meter voltage frequency> the upper limit
of frequency setting value
the action value 0
indicates to close the
alarm object
19
The lower limit
of frequency
Meter voltage frequency (nonzero)> the
lower limit of frequency setting
the action value 0
indicates to close the
alarm object
The upper
limit of power
The total value of primary active power >
the upper limit of power setting value
the action value 0
indicates to close the
alarm object
Voltage
open-phase
In three-phase four-wire, one phase or
two-phase in three voltage <110V
Three-phase three-wire ,one phase or
two-phase in three line voltage<190V
The alarm can be set
to turn on or off
Status 1 open Status 1 from the closed to the open The alarm can be set
to turn on or off
5.6.1 Alarm action condition
SPM33 generated alarm condition: the setting object meet the action conditions,
and need to meet the time requirements in order to be really activated.
Throughout the delay period, if the object is within the return limits, then the
alarm setpoint is not activated. If the delay time is 0, it means that once the
monitoring object is more limited, the alarm setpoint generated immediately.
There is a fixed value or more objects is active, the alarm is generated. After the
alarm is generated, all the setting object if returned within the limit, the alarm will
disappear.
20
5.6.2 Alarm Output
When the alarm occurs,
the ALARM lights will flash, meanwhile, the LCD panel
will pop up warning dialog box, then press key
to switch to the alarm
interface to view the type of event alarms, press key
to return to the
current interface. If don`t press key within 5s, alarm box will disappear. Alarms
type can also be read through communication, if the alarm associated relays,
the relay generates action. Once the alarm disappears, the ALARM light will be
off, the alarm interface will be displayed "no" at this time, if the alarm associated
relays, the relay will be reset.
6. Input/output Characteristics
6.1 Relay output
SPM33 provides two relay optional modes, relay specification is 250Vac/5A,
can be used with the instrument's alarm setpoint system, to monitor relative
electrical parameters whether there is more limited, and thus output breaker
reasonable action (details refer to the chapter of the alarm setpoint); Or can set
the relay to remote mode, customers can according to their need to relay control;
If you have special needs, please be specified when ordering.
21
SPM33 provides two relay operation modes. The action of relay is different
in these two modes. The default control mode of this product is remote control.
Users can modify to alarm control through panel relay setting or through
communication.
◆ Remote control (external) - The relay is controlled by a PC or PLC by
using commands through communication.
◆ Alarm Control (internal) - If there is an alarm generated, the relay on the
action, you can refer to specific alarm setpoint alarm.
◆ When setting as Alarm mode, Alarm Subject including All, Voltage, Current,
Frequency, Total active power, Voltage Phase lose, or DI 1 off, etc
Once the relay has been in the remote control mode, even if the alarms
generated, it will not act, the relay mode must be set to alarm mode, then can
operate the alarm action.
Reset (effective only under remote mode): When the relay acts, it can return to
the state after N times (N is set reset time, can be set by the panel and
communications, N = 0, the relay can`t reset, that is, relay will not restore to
original state).
Silencer: when elected relays, relay 1 in alarm mode, have a mute button
function simulation, when an alarm occurs, the relay 1 will have action, under
22
the alarm menu interface if press the "mute" button, relay 1 will be reset. After
the reset, if there is a new alarm generation, Relay 1 will re-action again.
Note: Relay 2 without this mute function.
6.2 Status input
SPM33 provides flexible 2-way nodes configurable input, applied to monitoring
circuit breaker position signal, switch position signals and other status
information.
SPM33 provides active status node, which need an external power source. The
following 2-way status input as example to introduce this wiring mode.
◇
External active node wiring diagram is shown as below：
In general, the external node is closed, SPM33 LCD corresponding status input
display is closed, while the internal state information is also set to 1; external
node is disconnected, SPM33 LCD corresponding status input display is turned
off, the internal state information is also set to 0.
23
6.3 Dual Source kWh measurement
DI 1 be defined as special function (register 40207), as dual source kWh
measurement function
After start this function:
If DI 1 with status of ON, add energy value to Grid area (register 40052-40063),
on the display will show Grid. And the value also will add to register
40026-40037.
If DI 1 with status of OFF, add total energy value to Generator area (register
40064-40075), on the display will show Gen. And the value also will add to
register 40026-40037.
Customer can query total energy, Grid energy and Gen energy from the page of
kWh (Active/ Reactive)
24
7. Technical Datasheet
Parameters
range
Rated
operating
parameters
Rated Power Supply AC 85~265V
DC 100~300V
Rated input current 5A or 1A
Rated input voltage 3×220/380V 35Hz~65Hz
Status input
Rated voltage
220V，2 channel active status input, less than
60V is open, more than 140V is closed，Max.
Input is 300V.
Relay output
Rated contact
capacity
AC 250V/5A or DC 30V/5A
parameter
range
Accuracy
Accuracy of
electric
parameters
voltage 10%~150% 0.5%
current 1%~120% 0.5%
Power factor -1~1 1%
Active energy 0~99999999.9 0.5%
Reactive energy 0~99999999.9 2%
Active power
Single phase：0 ~ ±
26MW/var/VA
To ta l：0 ~ ± 78MW/var/VA
0.5%
Reactive power 1.0%
Three-phase current
unbalance
0%~100% 1%
Harmonic content 0%~100%
B 级
parameters Performance
Power Consumption ≤ 2W/5VA
Cabinet
temperature
Normal operating
temperature
-10℃～+55℃
Limit operating
temperature
-25℃～+55℃
Storage temperature
-40℃～+70℃
Relative humidity
5％～95% RH, non-condensing
Insulation
ability
Power frequency
withstand voltage
2000VAC
Insulation resistance ≥ 100MΩ
Impulse voltage 6000V
IP index front panel IP52
25
case IP20
Project standard Test level
IEC
Electrostatic
Discharge Immunity
Tes t
GB/T17626.2-2006
(IEC61000-4-2:2001)
Class 4
Radiated immunity
test
GB/T17626.3-2006
(IEC61000-4-3:2002)
Class 4
Electrical fast
transient/burst
immunity test
GB/T17626.4-2008
(IEC61000-4-4:2006)
Class 4
Surge immunity test GB/T17626.5-2008
(IEC61000-4-5:2005)
Class 4
RF field immunity
induced mass
GB/T17626.6-2008
(IEC61000-4-6:2006)
Class 3
Radiated emissions
limit
GB 9254-2008
(CISPR22：2006)
Accord
Voltage dips, short
interruptions
immunity test
GB/T17626.11-2008
(IEC61000-4-11:2004)
Accord
Power frequency
withstand voltage
GB/T 17215.211-2006 Rated insulation
voltage≤300V，The
test voltage
2000V。
Rated insulation
voltage≤60V，The
test voltage
1000V。
Leakage current
≦10mA。
26
8. Communication protocol
8.1. Introduction
This document describes the input and output command, information and data
of the SPM33 under MODBUS communication mode. So it is convenient for the
3
rd
part using and developing.
8.1.1 Purpose of the Communication Protocol
The purpose of the SPM33 MODBUS communications protocol is to allow setup
information and measured data to be efficiently transferred between a
MODBUS Master Station and SPM33. It includes:
1) Allowing setting and reading all SPM33 set-up parameters from a MODBUS
Master Station.
2) Allowing reading all data measured by a SPM33 and SOE (Event log).
8.1.2 Version of Communication Protocol
This document is proper for all versions of SPM33 meters. It will be declared, if
any change happens later.
27
8.2. Detailed Description of the SPM33 Modbus Protocol
8.2.1. SPM33 Modbus Protocol Rules
The following rules define the protocol rules for information transfer between a
MODBUS Master device and the SPM33 in a RS-485 serial communications
loop.
1) All communications on the RS-485 loop conforms to a MASTER/SLAVE
scheme. In this scheme, information and data is transferred between a
MODBUS MASTER device and up to 32 SLAVE monitoring devices.
2) The MASTER will initiate and control all information transfer on the RS-485
communications loop.
3) Under no circumstances will a SLAVE device initiate a communications
sequence.
4) All communications activity on the RS-485 loop occurs in the form of
"PACKETS", a packet being simply a serial string of 8-bit bytes. The maximum
number of bytes contained within one packet is 255. The bytes that comprise a
packet consist of standard asynchronous serial data, which are generated using
equipment similar to that used for RS-232C.
5) The packages from MASTER are named request. The packages from
SLAVE are named response.
28
6) Under any circumstance, Slave can just respond one request.
8.2.2. Modes of Transmission
MODBUS protocol supports ASCII and RTU modes of transmissions. The
SPM33 supports only the RTU mode of transmission with 8 data bits, no parity,
and one stop bit.
8.2.3. Description of the Modbus Packet Structure
Every MODBUS packet consists of four fields:
1) The Address Field
2) The Function Field
3) The Data Field
4) The Error Check field
z Address Field
The address field is 1-byte long and identifies which slave device the
packet is for. Valid addresses range between 1 and 247. The slave device
whose address matches the value in this field will perform the command
specified in the packet.
z Function Field
The function field is 1-byte long and tells the addressed salve which function to
29
perform. Slave response packet should include same function field byte as
request. The Modbus functions supported by SPM33 are listed as below:
Function
Code
Meaning Action
0x01 Read Relay Output
Status
Obtains ON/ OFF information of one or
more relay output in SPM33 (0/1)
0x03 Read Holding
Registers
Obtains the current value in one or more
holding registers of the SPM33.
0x05 Relay control Write 0xFF00 to close (ON) the relay
Write 0x0000 to open (OFF) the relay
0x10 Preset Multiple
Registers
Places specific binary values into a series
of consecutive holding registers of the
SPM33
z Data Field
The length of Data Field is varies in length depending on its function. In general,
MODBUS supports “BIG INDIAN” mode, it means high-order byte first,
low-order byte second.
For example,
30
One 16 byte register value is 0x12AB; register is transmitted in below sequence:
High-order byte = 0x12
Low-order byte = 0xAB
z Error Check Field
In Modbus RTU mode, the 16-bit Cyclic Redundancy Check (CRC-16) is used.
The sending device calculates a 16-bit value, based on the information stored in
the address, function and data fields using the CRC-16 algorithm and appends
it to the end of the packet. The receiving device performs the same calculation
upon the reception of a packet. If the result does not match the checksum
stored in the packet, transmission errors have occurred and the packet will be
ignored by the receiving device.
For detail of CRC16 parity arithmetic, please refer to Section 4 .
8.2.4. Abnormal Responses
If a Modbus master device sends a non-effective command to a SPM33 or
attempts to read a non-effective holding register, an exception response will be
generated. The exception response consists of the slave address, function code,
error code, and error check field. The high order bit of the function code is set to
1 to indicate that the packet is an exception response.
31
Below list describes the meanings of exception codes:
Function Code Meaning
01 illegal function
code
SPM33 Modbus support the function code include: 01H,
02H, 03H, 05H, and 10H.
This code means the slave device receive an illegal
function code, or the SPM33 receive the error command.
02 illegal function
code
SPM33 receive the address referenced in the data field
is an invalid address.
03 illegal function
code
The requested register number is too long.
8.2.5. Broadcast Packets
SPM33 support broadcast commands when communicating in MODBUS mode.
Do write command 0x10 for timing.
32
8.3. Packet Communication
Two MODBUS functions are supported by the SPM33. The standard MODBUS
protocol supports only 16-bit registers, which limit the maximum value of any
measurement to 65535.
Section 3.1 will describe the format of Read/ Response Packet of relay output.
Section 3.2 will describe the format of Read/ Response Packet of holding
register.
Section 3.3 will describe the relay control command
Section 3.4 will describe Preset Multiple Registers packet and the acknowledge
packet.
8.3.1 Read the Relay Output Status (Function Code 01H)
Use 01 command to read the relay status. Relays are addressed starting at 0:
relay 1 is addressed as 0.
The relay status data in response packet is packed as one bit for one relay. 1=
ON, 0 = OFF.
The LSB (Least Significant Bit) of the first data byte contains the request
addressing output. Other relay is same as this, until to the high bit of this byte,
and rank from low bit to high bit in the followed byte.
If the return output Num. is not a multiple of 8, it will use zero to fill in the
33
remainder bit of last data byte (until to the high bit of the byte). The byte count
field specifies all byte num. of the data.
Request Packet
(Master→SPM33)
Response Packet
（SPM33→Master）
Unit ID/ Slave
address
1 byte Unit ID/ Slave
address
1 byte
01H (Function
Code)
1 byte 01H (Function
Code)
1 byte
Starting address 2 bytes Byte num. (N) 1 byte
Relay num. 2 bytes Relay status N bytes
CRC check code 2 bytes CRC check code 2 bytes
N = output num.÷ 8, if remainder ≠0, then N=N+1.
34
8.3.2. Read Holding Registers (Function Code 03H)
This command packet requests that the SPM33 responds all valid registers.
The value of reserved registers is 0.
Request Packet
(Master→SPM33)
Response Packet
(SPM33→Master)
Unit ID/ Slave
address
1 byte Unit ID/ Slave address 1 byte
03 H (Function
Code)
1 byte 03 H (Function Code) 1 byte
Start register
address
2 bytes Byte num.
(2 * register num.)
1 byte
Registers num. 2 bytes First register data 2 bytes
CRC check code 2 bytes Second register data 2 bytes
... ...
CRC check code 2 bytes
35
8.3.3 Relay Control (Function Code 05H)
Use 05 command to control the relay. Relays are addressed starting at 0
Data Field is 0xFF00, request the relay to be ON.
Data Field is 0x0000, request the relay to be OFF.
Request Packet
(Master→SPM33)
Response Packet
(SPM33→Master)
Unit ID/ Slave
address
1 byte Unit ID/ Slave address 1 byte
05 H (Function
Code)
1 byte 05 H (Function Code) 1 byte
Start register
address
2 bytes Start register address 2 bytes
Data field FF Data field FF
Data field 00 Data field 00
CRC check code 2 bytes CRC check code 2 bytes
36
8.3.4. Preset Multiple Registers (Function code 10H)
Preset Registers Format
(Master→SPM33)
Response Format
(SPM33→Master)
Unit ID/ Slave address 1 byte Unit ID/ Slave address 1 byte
10 H (Function Code) 1 byte 10 H (Function Code) 1 byte
Start register address 2 bytes Start register address 2 bytes
Register num. 2 bytes Register num. 2 bytes
Byte num.
(2 * register num.)
1 byte CRC check code 2 bytes
First register data
Second register data
...
CRC check code 2 bytes
This command packet allows the Master to program the SPM33 setup
parameters.
Note: SPM33 presume all registers are continuous from the first one.
37
8.4. Calculating the CRC-16 Error Check Field
This section describes the procedure for obtaining the CRC-16 error check field. A
packet can be considered as a continuous, serial stream of binary data (0, 1). The 16-bit
checksum is obtained by multiplying the serial data stream by 216 (10000000000000000)
and then dividing it by the generator polynomial x
16+x15+x2
+1, which can be expressed as
a binary data 11000000000000101. The quotient is ignored and the 16-bit remainder is the
checksum and is appended to end of the packet.
In calculating the CRC, all arithmetic operations (additions and subtractions) are
performed using MODULO TWO, or EXCLUSIVE OR operation.
Steps for the Generating the CRC-16 Checksum:
1) Form a new polynomial by dropping the MSB (Most Significant Bit) of the generator
polynomial and reversing the bit sequence. This yields the binary number 1010 0000 0000
0001 or A0 01 Hex.
2) Load a 16-bit register with initial value FF FF Hex.
3) Exclusive OR the first data byte with the loworder byte of the 16-bit register, storing the
result in the 16-bit register.
4) Shift the 16-bit register one bit to the right. If overflow bit is 1, then turn to step 5).
Otherwise, turn to step 6)
5a) If the bit shifted out to the right is one, Exclusive OR the 16-bit register with
38
the new generator polynomial, with result stored in the16-bit register. Return to step 4.
5b) If the bit shifted out to the right is zero, return to step 4.
6) Repeat steps 4 and 5 until 8 shifts have been performed.
7) Exclusive OR the next data byte with the 16-bit register.
8) Repeat steps 4 through 7 until all bytes of the packet have been calculate by XOR
9) The content of the 16-bit register is CRC-16
Procedure for Calculating the 6403 Bytes of 16 Hex.
Step Byte Action Register Bit# Shift
2 Initial Value 1111 1111 1111 1111
1 Load the first byte 0000 0000 0110
0100
3 XOR 1111 1111 1 0 01 10 11
4 SHIFT 1 bit to the right 0111 1111 1100 11 01 1 1
5a XOR polynomial 1101 1111 1100 1100
4 SHIFT 1 bit to the right 0110 1111 1110 0110 2 0
4 SHIFT 1 bit to the right 0011 0111 1111 0 011 3 0
4 SHIFT 1 bit to the right 0001 1 011 1111
1001
4 1
39
5a XOR polynomial 1011 1011 1111 1000
4 SHIFT 1 bit to the right 0101 1101 1111 1100 5 0
4 SHIFT 1 bit to the right 0010 1110 1111 1110 6 0
4 SHIFT 1 bit to the right 0001 0111 0 111 1111 7 0
4 SHIFT 1 bit to the right 0000 1011 1011 1111 8 1
5a SHIFT 1 bit to the right 1010 1011 1011
1110
2 Load the second byte 0000 0000 0000
0011
7 XOR 1010 1011 1011
1101
4 SHIFT 1 bit to the right 0101 0101 1101
1110
1 1
5a XOR polynomial 1111 0101 110 1 1111
4 SHIFT 1 bit to the right 0111 1010 1110 1111 2 1
5a XOR polynomial 1101 1010 1110 1110
4 SHIFT 1 bit to the right 0110 1101 0111 0111 3 0
40
4 SHIFT 1 bit to the right 0011 0110 1011
1011
4 1
5a XOR polynomial 1001 0110 1011
1010
4 SHIFT 1 bit to the right 0100 1011 0101
1101
5 0
4 SHIFT 1 bit to the right 0010 0101 1010
1110
6 1
5a XOR polynomial 1000 0101 1010
1111
4 SHIFT 1 bit to the right 0100 0010 1101
0111
7 1
5a XOR polynomial 1110 00 1 0 1101
0110
4 SHIFT 1 bit to the right 0111 0001 0110
1011
8 0
CRC-16 0111 0001 0110
1011
41
8.5. Description of SPM33 Registers
All SPM33 measured and setup parameters are treated as HOLDING
REGISTERS having addresses 4xxxx when communicating in MODBUS
protocol. According to the MODBUS Protocol, in response to a request for
register 4xxxx of a particular slave device (SPM33), the MODBUS master
reads register xxxx-1 from the slave (SPM33). For example register 40011
corresponds to register 10.
8.6 Description of Data Types
UINT16 Unsigned 16-digit integer
INT16 Signed 16-digit integer
LUINT32 Unsigned 32-digit integer
LINT32 Signed 32-digit integer
WORD16
Bit denotation word, applicable to on-off and relay status.
D0 refers to the first on-off or relay channel.
D1 refers to the second on-off or relay channel.
The rest bits may be deduced by analogy.
Bit 0 refers to “off”, and bit 1 refers to “on”.
42
8.6.1 Real-time data register list
Regist
er
addres
s
Read/w
rite
attribut
e
Definition Data
Type
Description
40001 RO Phase A voltage UINT16 Secondary side L-N
voltage, Calculation
factor: 0.01,
unit: V
40002 RO Phase B voltage
40003
RO Phase C voltage
40004 RO Line AB voltage UINT16 Secondary side L-L
voltage, Calculation
factor: 0.01,
unit: V
40005 RO Line BC voltage
40006
RO Line CA voltage
40007 RO Phase A current
UINT16
Secondary Side current,
Calculation factor: 0.001,
unit: A. If use CT, then
customers need to
multiply by CT ratio.
40008 RO Phase B current
40009 RO Phase C current
40010 RO Neutral current
40011
RO Total active power low word
LINT32
Secondary side active
43
40012
RO Total active power high
word
power. Calculation factor:
0.1, unit: W. If use CT,
then customers need to
multiply by CT ratio.
40013
RO Total reactive power low
word
LINT32
Secondary side reactive
power. Calculation
factor: 0.1, unit: var. If use
CT, then customers need
to multiply by CT ratio. 40014
RO Total reactive power high
word
40015
RO Total power factor INT16 Calculation factor: 0.001.
40016
RO Phase A active power
INT16 Secondary side active
power. Calculation
factor: 0.1, unit: W. If use
CT, then customers need
to multiply by CT ratio.
Only when it is 3 phase 4
wires connection mode
can the value valid.
40017
RO Phase B active power
40018
RO Phase C active power
40019
RO Phase A reactive power
INT16 Secondary side reactive
power. Calculation
44
40020
RO Phase B reactive power
factor: 0.1, unit: W. If use
CT, then customers need
to multiply by CT ratio.
Only when it is 3 phase 4
wires connection mode
can the value valid.
40021
RO Phase C reactive power
40022 RO Phase A power factor
INT16 Calculation factor: 0.001.
Only when it is 3 phase 4
wires connection mode
can the value valid.
40023 RO Phase B power factor
40024 RO Phase C power factor
40025
RO Frequency
UNIT16 Calculation factor: 0.01,
unit: Hz
40026
RO Total active energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kWh
Range: 0-99,999,999.9
40027
Total active energy high
word
40028
RO Total reactive energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kvarh
Range: 0-99,999,999.9
40029
Total reactive energy low
word
45
40030
RO Input active energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kWh
Range: 0-99,999,999.9
40031
Input active energy high
word
40032
RO Output active energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kWh
Range: 0-99,999,999.9
40033
Output active energy high
word
40034
RO Input reactive energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kvarh
Range: 0-99,999,999.9
40035
Input reactive energy high
word
40036
RO Output reactive energy low
word
LUINT3
2
Calculation factor: 0.1,
unit: kvarh
Range: 0-99,999,999.9
40037
Output reactive energy high
word
40038 RO On-off status WORD1 D0 means 1 channel
46
6 D1 means 2 channel
0 means off
1 means on 40039
RO Relay status
40040
RO Alarm status WORD16 1 means alarm, 0 means
no alarm
Bit 1: over voltage
Bit 2: under voltage
Bit 3: over current
Bit 4: under current
Bit 5: Frequency too high
Bit 6: Frequency too low
Bit 7: over load
Bit 8: phase loss
Bit 9: Status 1 off
40041 RO CT Ratio
40042 RO Reserved
40043
RO Average phase voltage UINT16 Calculation factor: 0.01,
unit: V
47
40044
RO Average line voltage Calculation factor: 0.01,
unit: V
40045
RO Average phase current UINT16 Calculation factor: 0.001,
unit: A
40046
RO Current unbalance rate Calculation factor: 0.001
40047 RO Phase A apparent power UINT16 Calculation factor: 0.1,
unit: VA
40048 RO Phase B apparent power
40049 RO Phase C apparent power
40050
RO Total apparent power low
word
LUINT3
2
40051
Total apparent power high
word
40052 RO Grid Input Active Power Primary measurement Power,
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9 40053
40054 RO Grid Output Active Power Primary measurement Power,
48
40055
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9
40056 RO Grid total Active Power Primary measurement Power,
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9 40057
40058 RO Grid Input Reactive Power Primary measurement Power,
calculator factor 0.1, unit: kvarh
First is low byte, second is high byte
Range: 0-99,999,999.9 40059
40060 RO Grid Output Reactive Power Primary measurement Power,
calculator factor 0.1, unit: kvarh
First is low byte, second is high byte
Range: 0-99,999,999.9 40061
40062 RO Grid total Reactive Power Primary measurement Power,
calculator factor 0.1, unit: kvarh
First is low byte, second is high byte 40063
49
Range: 0-99,999,999.9
40064 RO Generator Input Active
Power
Primary measurement Power,
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9 40065
40066 RO Generator Output Active
Power
Primary measurement Power,
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9 40067
40068 RO Generator total Active
Power
Primary measurement Power,
calculator factor 0.1, unit: kWh
First is low byte, second is high byte
Range: 0-99,999,999.9 40069
40070 RO Generator Input Reactive
Power
Primary measurement Power,
calculator factor 0.1, unit: kvarh
First is low byte, second is high byte
Range: 0-99,999,999.9 40071
40072 RO Generator Output Reactive Primary measurement Power,
50
40073
Power calculator factor 0.1, unit: kvarh
First is low byte, second is high byte
Range: 0-99,999,999.9
40074 RO Generator total Reactive
Power
Primary measurement Power,
calculator factor 0.1, unit: kvarh
First is low byte, second is high byte
Range: 0-99,999,999.9 40075
40076
RO Ferroelectric fault register Factory using
0: Normal
1. Abnormal
40077
RO Inside REF sampling real
time value
51
8.6.2 List of demand data registers
Regist
er
addres
s
Read
/write
attrib
ute
Definition Data
type
Description
40701 RO Phase A current demand UINT16 Calculation factor:
0.001, unit: A
40702 RO Phase B current demand
40703 RO Phase C current demand
40704 RO Phase A active power demand UINT16 Calculation factor:
0.1, unit: W
40705 RO Phase B active power demand
40706 RO Phase C active power demand
40707 RO Total active power demand low word LINT32 Calculation factor:
0.1, unit: W
40708 Total active power demand high word
40709 RO Maximum phase A current demand UINT16 Calculation factor:
0.001, unit: A
40710 RO Maximum phase B current demand
40711 RO Maximum phase C current demand
40712 RO Maximum phase A active power Calculation factor:
52
demand UINT16 0.1, unit: W
40713
RO Maximum phase B active power
demand
40714
RO Maximum phase C active power
demand
40715
RO Total active power demand
low word
LUINT3
2
Calculation factor:
0.1, unit: W
40716
Total active power demand
high word
40717 RO Phase A reactive power demand 10 times, unit: var
40718 RO Phase B reactive power demand 10 times, unit: var
40719 RO Phase C reactive power demand 10 times, unit: var
40720 RO Total reactive power demand 10 times, unit: var
40721
40722 RO Phase A apparent power demand 10 times, unit: VA
40723 RO Phase B apparent power demand 10 times, unit: VA
40724 RO Phase C apparent power demand 10 times, unit: VA
53
40725 RO Total apparent power demand 10 times, unit: VA
40726
40727
RO Phase A reactive power Maximum
demand
10 times, unit: var
40728
RO Phase B reactive power Maximum
demand
10 times, unit: var
40729
RO Phase C reactive power Maximum
demand
10 times, unit: var
40730 RO Total reactive power Maximum
demand
10 times, unit: var
40731
40732
RO Phase A apparent power Maximum
demand
10 times, unit: VA
40733
RO Phase B apparent power Maximum
demand
10 times, unit: VA
40734
RO Phase C apparent power Maximum
demand
10 times, unit: VA
40735
RO Total apparent power Maximum
demand
10 times, unit: VA
54
8.6.3 List of harmonic data registers
Register
address
Rea
d/wr
ite
attri
bute
Definition
Data
type
Description
40801 RO Va - THD UINT16 Calculation factor:
0.001
40802
RO Vb - THD
40803 RO Vc - THD
40804 RO Ia – THD UINT16
Calculation factor:
0.001
40805 RO Ib – THD
40806 RO Ic – THD
40807 RO 2nd harmonic component of Va UINT16
Calculation factor:
0.001, Unit: %
40808 RO 3rd harmonic component of Va
55
40809
-40835
RO …
40836 RO 31st harmonic component of Va
40837 RO 2nd harmonic component of Vb UINT16
Calculation factor:
0.001, Unit: %
40838 RO 3rd harmonic component of Vb
40839
-40865
RO …
40866 RO 31st harmonic component of Vb
40867 RO 2nd harmonic component of Vc UINT16
Calculation factor:
0.001, Unit: %
40868 RO 3rd harmonic component of Vc
40869
-40895
RO …
40896 RO 31st harmonic component of Vc
40897 RO 2nd harmonic component of Ia UINT16
Calculation factor:
0.001, Unit: %
40898 RO 3rd harmonic component of Ia
40899
-40925
RO …
56
40926 RO 31st harmonic component of Ia
40927 RO 2nd harmonic component of Ib UINT16
Calculation factor:
0.001, Unit: %
40928 RO 3rd harmonic component of Ib
40929
-40955
RO …
40956 RO 31st harmonic component of Ib
40957 RO 2nd harmonic component of Ic UINT16
Calculation factor:
0.001, Unit: %
40958 RO 3rd harmonic component of Ic
40959-409
85
RO …
Calculation factor:
0.001, Unit: %
40986 RO 31st harmonic component of Ic
Calculation factor:
0.001, Unit: %
57
8.6.4 List of configuration registers
Register
address
R&W
attribute
Definition Description
40201 RW Communication Address 1--247
40202 RW CT ratio 1--10000
40203
RW Connection mode 0--1
0 ： 3 phase 4 wire
1：3 phase 3 wire
40204 RO Reserved Read only
40205 RO Reserved Read only
40206
RW
Baud rate
0--1
0：4800
1：9600
40207
RO Reserved Read only
40208
RO Reserved Read only
40209
RO Reserved Read only
58
40210
RW
Current Channel of 1st
Voltage mapping
Default 1, 1st forward current
1 means 1st forward current
2 means 2nd forward current
3 means 3rd forward current
0x8001 means 1st reverse current
0x8002 means 2nd reverse current
0x8003 means 3rd reverse current
40211
RW
Current Channel of 2nd
Voltage mapping
Default 2, 2nd forward current
1 means 1st forward current
2 means 2nd forward current
3 means 3rd forward current
0x8001 means 1st reverse current
0x8002 means 2nd reverse current
0x8003 means 3rd reverse current
40212
Default 3, 3rd forward current
1 means 1st forward current
59
RW
Current Channel of 3rd
Voltage mapping
2 means 2nd forward current
3 means 3rd forward current
0x8001 means 1st reverse current
0x8002 means 2nd reverse current
0x8003 means 3rd reverse current
40213
RW
Working status of relay 1
0—1, default 0, remote
0 means remote control
1 means auto alarm
40214
RW
Return time of relay 1
Default 0
0~120 (s)
0 means blocking.
40215
RW
Working status of relay 2
0—1, default 0, remote
0 means remote control
1 means auto alarm
40216
RW
Return time of relay 2
Default 0
0~120 (s)
0 means blocking.
40217 Reserved
60
40218 Reserved
40219 Reserved
40220 Reserved
40221
RW Operation value of
voltage upper limit
Calculation factor: 0.01, Unit:V
0 means closed
For 110V – 500V, default 0.
40222
RW Action time of voltage
upper limit
0-120s。
40223
RW Operation value of
voltage lower limit
Calculation factor: 0.01, Unit:V
0 means closed
For 110V – 500V, default 0.
40224
RW Action time of voltage
lower limit
0-120s。
40225
RW
Operation value of
current upper limit (low
word)
Primary value of current.
Calculation factor: 0.1, Unit: A
0 means closed
1.0A-60000.0A
40226
Operation value of
current upper limit (high
61
word)
40227
RW Action time of voltage
upper limit
0-120s
40228
RW
Operation value of
current lower limit (low
word)
Primary value of current.
Calculation factor: 0.1, Unit: A
0 means closed
1.0A-60000.0A
40229
Operation value of
current lower limit (high
word)
40230
RW Action time of voltage
lower limit
0-120s
40231
RW Operation value of
frequency upper limit
Calculation factor: 0.01, Unit: Hz
0 means closed
45Hz – 65Hz
40232
RW Action time of frequency
upper limit
0-120s
62
40233
RW Operation value of
frequency lower limit
Calculation factor: 0.01,
Unit: Hz
0 means closed
45Hz – 65Hz
40234
RW Action time of frequency
lower limit
0-120s
40235
RW Operation value of active
power upper limit (low
word)
Primary side value
Calculation factor: 0.1,
Unit: kW
0.1-40000.0kW
40236
Operation value of active
power upper limit (high
word)
40237
RW Action time of active
power upper limit
0-120s
40238
RW Setting for phase loss
alarm
0 means closed
1 means open
When phase A or phase B < 110V,
it means phase loss.
63
When phase A, phase B and phase
C all < 110V, it means work normal.
40239
RW Alarm status 0 means closed
1 means open.
Note: Register 40221—40239 should be set once time. What’s more, the upper limit must
higher than lower limit.
8.6.5 Register for command and clear energy
Register
address
Read/write
attribute
Data
type
Definition Description
40252 WO U16 Clear Maximum
value of demand
Write 888
40253 WO U16 Clear energy Write 78
40254 WO U32 Input active energy Calculation factor: 0.1,
Unit: kWh
40255
40256 WO U32 Output active
energy
40257
40258 WO U32 Input reactive Calculation factor: 0.1,
64
40259 energy Unit: kvarh
40260 WO U32 Output reactive
energy
40261
Note: Register 40254~40261 should be read /write once time
8.6.6 List of device information registers
Register
address
Read/write
attribute
Definition Description
49001 RW Device No.
49002
49003 WO Recover user system Write 888
49004 WO Recover factory setting Write 888
49005 RO Firmware version 1.0.5 <Main version>.<Sub
version>.<modify version>
49006 RO Hardware version 1.0.5 <Main version>.<Sub
version>.<modify version>
65
9. Maintenance and Trouble Shooting
Possible
problem
Possible cause Possible solution
There is no
display on device
after impose
power supply.
The power supply fails to
be imposed on the meter.
Check if the correct working voltage
has been imposed on the L/+ and N/-
terminals of the meter.
Check if the fuse for the control power
supply has been burnt down.
The measured
value is not
correct or does
not conform to the
expectation.
The voltage
measurement is not
correct.
Check if the neutral point has been
connected reliably.
Check if the measured voltage
matches the rated parameter of the
meter.
Check if the PT ratio has been set
correctly.
The current
measurement is not
correct.
Check if the measured current
matches the rated parameter of the
meter.
66
Check if the CT ratio has been set
correctly.
The power measurement
is not correct.
Check if the measurement mode has
been set correctly.
Check if the phase sequence
corresponding to the voltage and the
current is correct.
Check if the current terminals of the
same name are wrong.
The digital input
status no
changing.
The voltage relating to
digital input is not correct.
Check if the types of external nodes
match the rated parameters of the
meter.
Check if the external connection is
correct.
The relay output
status no
changing.
The relay does not
receive the control
command.
Check if the communication link is
correct.
The control mode of relay Check if the current relay is under the
67
is not correct. correct mode.
There is no
communication
between the
upper end device
and the meter
The communication baud
rate of the meter is not
correct.
Check if the communication baud rate
of the meter is consistent with its
definition.
The communication link
has not been connected
to the terminal resistor.
Check if the 120-Ohm resistor has
been connected.
The communication link
suffers interference.
Check if the communication-shielding
layer has been earthed effectively.
The communication line
is interrupted.
Check if the communication cable has
been disconnected.
The communication baud
rate of the meter is not
correct.
Check if the communication baud rate
of the meter is consistent with its
definition.
68
10. Appendix 1
10.1 Terminals Definition
No. Definition Instruction No.
Definiti
on
Instruction
1 L/+
Positive pole of
power supply
2 NC Null
3 N/-
Negative pole of
power supply
4 NC Null
5 S1 Status input 1 6 S2 Status input 2
7 SG
Status input
public GND
8 RL1
Relay 1 output
1
9 RLN1 Relay 1 Output 2 10 RL2
Relay 2 Output
1
11 RLN2 Relay 2 Output 2 12
RS485
-
485 positive
pole
13 RS485+ 485 positive pole 14 SHLD RS485 shield
15 VA phase A voltage 16 VB
phase B
voltage
17 VC phase C voltage 18 VN Neutral line
19 I11
Phase A current
incoming line
20 I12
Phase A current
outgoing line
21 I21
Phase B current
incoming line
22 I22
Phase B
current
outgoing line
23 I31
Phase C current
incoming line
24 I32
Phase C
current
outgoing line
69
10.2 Typical Connection
SPM33 supports multiple connection modes of measurement, the following
methods were used icons explained.
A
B
C
N
A
B
C
Vector of three-phase four-wire
system
Vector of three-phase three-wire
system
■ three-phase four-wire system：
70
■ three-phase three-wire system，3CT：
■ three-phase three-wire system，2CT：
71
SPM33 typical wiring diagrams, comprehensive electrical parameters
measuring under three-phase four-wire mode, with digital status inputs and one
RS485 communication function:
72
Notice:
z PILOT reserves the right to modify this manual without prior notice in view
of continued improvement.
z Technical Consulting: +86 15916202620
z After-sale Services: +86 15916202800
z Email: pilot006@pmac.com.cn
Zhuhai Pilot Technology Co., Ltd.
Add: No. 15, Keji 6 Road, Chuangxin Haian, Tangjia High-tech Zone, Zhuhai,
Guangdong, 519085 China
Tel: +86 -756-3629926
Fax: +86-756-3629600/ 3629670
http://www.pmac.com.cn
Loading...