SCHNEIDER PowerPact ™ H. Modbus Communication User Guide for J and L-type Circuit Breakers

SCHNEIDER PowerPact ™  H. Modbus Communication User Guide for J and L-type Circuit Breakers

Schneider PowerPact ™  H. The Modbus communication user guide for J and L-type circuit breakers covers four core contents: communication interfaces (IFM/IFE), Modbus protocol specifications, module registers and commands, and data acquisition and control. It clarifies the hardware configuration and communication parameters of IFM (RS-485 serial line) and IFE (Ethernet) interfaces, and lists in detail the register addresses, data types, and read-write rules of standard/old datasets, MicroLogic trip units, BSCM modules, and IO modules. It provides the execution process of remote commands such as circuit breaker opening and closing, parameter configuration, etc., while emphasizing safety operation standards (such as password management and permission control), suitable for remote monitoring and control in industrial distribution scenarios.

Document Overview

(1) Core positioning and scope of application

Category key information

Document Purpose: PowerPact ™  H. Installation, configuration, and operation guide for Modbus communication of J and L-type circuit breakers

Circuit breakers with firmware versions that meet the requirements (such as IMU module firmware ≥ V001.003.000)

The core value is to achieve remote reading of measurement data, diagnostic information, control of circuit breaker opening and closing, and configuration of protection parameters

Safe operation must be carried out by qualified electrical personnel, strictly following password management and permission control

(2) Compliance and reference standards

International standards: IEC/EN 60947-4-1, UL 508, CSA C22.2 No.14

Network Security: First use requires changing default password, disabling unused ports, deploying multi-layer network defense

Related documents: PowerPact Circuit Breaker User Guide, MicroLogic Release Unit User Guide, ULP System User Guide

Communication interface configuration

(1) IFM interface (Modbus SL)

Detailed parameters of configuration items

Part number LV434000 (replaces TRV00210/STRV00210)

Communication interface RJ45 port (Modbus SL), stacking interface (optional TRV00217)

Address setting rotary switch definition (1-99), default address 99, address 0 reserved for broadcasting

The power requirement is 24Vdc. It is recommended to use UL certified Level 2 power supply (maximum 3A) and only connect with copper wires

Padlock function enabled: Enable remote control command; Closed: Disabled (except for the 'Set Time' command only)

Automatic configuration method: detect baud rate (4800/9600/19200/38400) and parity; Manual configuration: through EcoStruxure Power Commission software

(2) IFE interface (Ethernet)

Detailed parameters of configuration items

Type and Part Number Single Circuit Breaker Interface (LV434001/LV434010), Ethernet Server (LV434002/LV434011)

Communication interface dual RJ45 ports (supporting daisy chain connection), no ring topology protection

IP configuration defaults to DHCP, which can be restored to default by pressing the reset button (1-5 seconds)

The power requirement is 24Vdc, and the stacked IFM interface is powered by the IFE server

The padlock function is the same as the IFM interface, only the "set time" command is not restricted

Featured features include embedded configuration/monitoring of web pages, device discovery services, email alert notifications

Modbus protocol specification

(1) Basic rules of communication

Master slave mode: 1 master device (monitor/PLC), up to 31 slave devices (circuit breakers)

Frame structure: Device address (1 byte) → Function code (1-2 bytes) → Data (n registers) → CRC16 checksum (2 bytes)

Response time: Typical<10ms, maximum value 700ms, recommended request interval ≥ 1 second

Data storage: INT32/64 type adopts Big Endian format (the most significant bit is transmitted first)

(2) Core functional code

Function code name usage restrictions

0x03 Read Hold Register Read Output/Internal Register (such as measurement value, status) Up to 52 registers

0x04 Read Input Register Read Input Register (such as sensor data) Up to 52 registers

0x06 Preset a register to write a single parameter (such as protection threshold)-

0x10 Preset multiple register batch write parameters (such as multiple protection settings) up to 52 registers

0x2B (sub function 0x0F/0x10) Get/set date and time synchronization from device time support broadcast synchronization

0x08 Diagnostic Function Management Counter (such as Bus Error Count)-

(3) Exception code description

Common reasons for the meaning of abnormal codes

0x01 The function code for the illegal function request is not supported

0x02 Illegal data address register address does not exist or is not compatible with firmware version

0x03 Illegal data value written to parameter exceeds allowed range

0x06 Busy device processing other commands

0x07 Negative confirmation programming request cannot be executed

Data collection and registers

(1) Dataset classification

Dataset type, register range, core content advantages

Standard dataset 32000-32341: Circuit breaker status, tripping reasons, current/voltage/power/energy, fast response to harmonic distortion, including high-precision data

The old dataset 12000-12165 is compatible with old devices and includes basic measurement values and status. A single request can read 114 registers

(2) Core module register

① MicroLogic trip unit (key register)

Register type, address range, core data update frequency

Real time measurement of 1000-1146 phase current (IA/IB/IC), line voltage (VAB/VBC/VCA), frequency of 1 second

Electricity measurement 2000-2031 Total active energy (kWh), total reactive energy (kVARh) 5 seconds

Protection parameter 8754-8930: Long delay Ir, short delay Isd, and instantaneous Ii settings are updated as needed

Log register 5732-29549 alarm logs (10 entries), trip logs (17 entries), maintenance logs (10 entries) event triggers

② BSCM module (circuit breaker status control)

Register type, address range, core data function

Status registers 563-564 Real time monitoring of circuit breaker opening and closing status and electric mechanism mode

Counter 571-582 opening and closing times, command execution times, threshold setting (default 5000), maintenance warning

Event log 602-652 10 event records (including timestamp and event type) fault tracing

③ IO module

Register Type Address Range (IO1) Core Data Function

Analog input 13824-13929 Pt100 temperature (-50~250 ℃), data validity, environmental monitoring

Digital input/output 13930-14000 6-channel input status, 3-channel output status switch control

Alarm status 203-205 User defined alarm (201-210) Activation status abnormal warning

Remote Command and Control

(1) Command execution process

Load command parameters into buffer (registers 8000-8015)

Send requests through Modbus function 16 (write multiple registers)

Read command status register 8021 and confirm if it is being executed (0x0003)

Verify if the command code of register 8020 matches the request

Read error code (register 8021 least significant bit), 0 indicates successful execution

(2) Example of Key Commands

Command Name Command Code Permission Requirements Core Parameters

Circuit breaker opening 904 administrator/operator has no additional parameters

Circuit breaker closing 905 administrator/operator has no additional parameters

Reset minimum/maximum value 46728 Administrators/operators need to specify the reset object (current/voltage/power, etc.)

Long delay protection setting 45192 administrator Ir setting value, tr delay (500~16000ms)

Password Modification - Administrator Old Password+New Password (4 ASCII characters)

(3) Permission and Security Control

User profiles: Administrator (highest authority), Service, Engineer, Operator (hierarchical authority)

Password rule: Default password (0000/111/2222/3333), must be changed for the first use

Write protection: dual protection of hardware padlock and software password to prevent illegal modification of protection parameters

Log audit: All operations (command execution, parameter modification) are recorded with timestamp logs

Safety and Maintenance Standards

Operation requirements: Installation and maintenance must be carried out by qualified electrical personnel, and wiring specifications must be strictly followed

Network Security: Disable unused ports/accounts, deploy firewalls, network segmentation

Firmware update: Ensure compatibility through EcoStruxure Power Commission software update

Maintenance indicator: By reading the usage time, contact wear rate, and tripping times of the circuit breaker through the register, a maintenance warning is triggered