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Modbus power control license bluelog Neo data sheet

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Modbus Power Control
bluelog Neo

Item no. 557.402

Modbus interface for real-time process data exchange with the grid operator.

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Description

The Modbus Power Control interface is an open Modbus TCP interface. It facilitates the real-time process data exchange with the grid operator. If telecontrol protocols (IEC 60870-5-101/-104, IEC 61850 or DNP3) are used, the interface is the ideal connection between a protocol converter (for example programmable logic controller - PLC) and the telecontrol system of the grid operator.

Features

  • Modbus TCP interface

  • Setpoint commands given by the grid operator (active power curtailment, power factor (cos ϕ) control, reactive power control)

  • Interface for protocol converter of telecontrol protocols (IEC 60870-5-101 /-104, IEC 61850 or DNP3)

  • Switching between different methods for active / reactive power management

  • Setting of reference voltage for parallel shift of the characteristic curve Q (V)

  • Feedback (acknowledgement) of setpoint commands for signal monitoring

  • Feedback of electrical parameters measured at grid connection point (for example P, Q, cos φ, f, V, I)

Requirements

  • bluelog Neo

  • 557.402 Modbus Power Control bluelog Neo license. The license is issued for a specific bluelog Neo. When ordering, provide the 14-digit hardware serial number of your data logger.

Modbus specification

Communication parameters

  • Slave ID (Client ID): 1

  • Port: 502

  • Delay: 1,000 ms

General register definition

  • If a device does not deliver a measured value, a missing value will be sent instead. See table “Data types” below.

    • Missing values int: 0x80000000 | float: 0x7FC00000

  • Read values: Function code 03 - Read holding registers

  • Write values: Function code 16 - Preset multiple registers

  • Register and byte order:

    • The word order is LOW register before HIGH register (Little Endian)

    • The byte order is HIGH byte before LOW byte (Big Endian) → 0xCCDDAABB

Example

Command with mbpoll

Write command to limit the feed-in of active power to 10%.

mpc_modbus-specification_neo (1).svg
Example setpoint via Modbus power control



Data types

Abbreviation

Description

Missing values

U16

16-bit unsigned integer

0xFFFF

U32

32-bit unsigned integer

0xFFFFFFFF

I16

16-bit signed integer

0x8000

I32

32-bit signed integer

0x80000000

F32

32-bit float

0x7FC00000

String

  • String, ASCII encoding.

  • If the whole length of the field is used, then the end of the string will be filled with 0x00.

  • If a value (for example model name) does not fit in the register, then it will be cut off.

0x00


Interface registers

This PDF provides an overview of the registers:
Modbus-Power-Control_Neo_registers_en_2026-02-17.pdf