C-Tran Transducer


C-Tran Transducer

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M552 C-Tran Introduction

The M552 C-Tran is a Current Transformer complete with an integrated, fully programmable, three phase power transducer. It provides two isolated RS485 communication ports both using Modicon's Modbus protocol.
The transducer's accuracy is class 0.2% for voltage and current signals down to 10% Un and 10% In, class 0.3 for power measurements and 1% of reading for energy measurements. (IEC1036), 50-60Hz.

The CT is class 1%

The M552 C-Tran measures Voltages, Currents, Import/Export Power (W, VAr, VA), True Power Factor, Frequency, Import/Export Demands(Wd, VArd, VAd, Ad) and Import/Export Energy and Hours Run

All measured quantities can be obtained from the transducer, the system's parameters can be set up remotely, important data can be saved to computer and the order of the Modbus registers themselves can be changed.

A second RS485 port can be used to drive up to 31 LCD meter style terminals.

Product Code M552-CTR
Nominal input voltage 280/485V AC
Nominal input current 100A AC
System Frequency 50Hz


M552 C-Tran specification

Rated Un:
Directly connected voltages:
(3ph4W) 100V to 330VL-N MAX
(3ph3W) 100V to 440VL-L MAX
Range 280V or 140V nominal
Rated In:
Rated In: dependent on CT primary (see below) Range 0-120% In
CT primary options:
100A, 125A, 150A, 160A, 200A, 250A
Frequency 50/60 Hz nominal range
45/65Hz working


Absolute maximum input: 4 x In

Specified at 23°C, 100V to Un, 10% to In
Integrated Transducer:
Parameters (unless stated) Class 0.3% to IEC 688 Voltage and Current Class 0.2% to IEC 688 Frequency Class 0.1 to IEC 688
Active & Reactive Energy 1% of reading to IEC1036 Current transformers: Class 1%

Self-powered: maximum 440V
Burden <10VA  

Working Temperature 0 to +60 deg C
Storage Temperature -30 to +65 deg C
Temperature Coefficient 0.01% per deg C

UL, C-UL Pending

Installation category III (480 VAC ph/ph)
Degree of pollution 2
Test Voltage:
4 kV RMS 50 Hz for 1 min voltage inputs to case . 3kV RS485 to case and voltage inputs.
(There is no isolation between Port 1 and Port 2) Impulse Test:
EMC 5kV transient complying with IEC 801/EN  55020 HF
 Electromagnetic Compatibility
Immunity to:-
electrostatic discharges: IEC 61000-4-2-Level III radiated radio-Hz fields: IEC 61000-4-3-Level III electrical fast transient/bursts: IEC 61000-4-4-Level III impulse waves: IEC 61000-4-5-Level III
conducted disturbances: IEC 61000-4-6-Level III voltage dips: IEC 61000-4-11
short interruptions: IEC 61000-4-11
Emissions to:-
Conducted and radiated: CISPR11-Class A

Applied Standards
General IEC 688 BSEN60688, BS4889, IEC 359
EMC Emissions EN61326-1
Immunity EN61326-2
Safety EN61010-1


Port 2:
Serial communication RS485 using Modbus protocol
Programmable Baud Rate 2400,4800,9600,19200,38400,57600
Parity Odd, Even or None
Auto Detection RS485
Port 1:
Serial communication RS485 using Modbus protocol
Fixed format: 8 data bits, Even parity, 1 stop bit
Programmable Baud Rate and floating point Endian