BENDER LINETRAXX® CTUB100 series AC/DC sensitive measuring current transformers (type B)

BENDER LINETRAXX ®  CTUB100 series AC/DC sensitive measuring current transformers 

Product Overview

Bender LINETRAXX ®  The CTUB100 series is an AC/DC sensitive measuring current transformer designed specifically for residual current monitoring. It adopts a "electronic module+transformer core" modular structure that can be combined. Its core advantages include supporting AC/DC current signal conversion, replaceable modules (without separating primary conductors), adaptability to multiple evaluation devices, and some models have full magnetic shielding, which can withstand high load currents and surge currents. The product complies with international and railway industry standards and is widely used in industrial control systems, railway vehicles, and other scenarios that require high accuracy and stability in current monitoring.

Core components and specification parameters

（1） Types and Differences of Electronic Modules

Module model, power supply voltage adaptation equipment, key characteristics, product number

CTUB101 DC ± 12V RCMA420/423 with T terminal, output full range 8A B78120050

CTUB102 DC24V RCMS4 series, EDS441-LAB replaces CTUB104, supports maximum positioning current of 25mA B78120051

CTUB105 DC24V RCMS4 series measurement range 3 fixed non adjustable B78120054

（2） Specification of transformer core

Is the inner diameter of the iron core model equipped with magnetic shielding and weight? Product number

CTBC20 20mm No ≤ 230g B98120001

CTBC20P 20mm is ≤ 290g B98120002

CTBC35 35mm No ≤ 310g B98120003

CTBC35P 35mm is 390g B98120004

CTBC60 60mm No ≤ 530g B98120005

CTBC60P 60mm is ≤ 690g B98120006

CTBC120 120mm No ≤ 1460g B98120007

CTBC120P 120mm is 1820g B98120020

CTBC210 210mm No ≤ 4290g B98120008

CTBC210P 210mm is 4940g B98120021

（3） Core technical parameters

Category specific parameters

Output characteristics: Output terminals S1 (k) and S2 (l); Scale 400mV/1A; Maximum voltage ± 10V

Power supply requirements CTUB101: DC ± 12V; CTUB102/105: DC24V

Environmental adaptability working temperature -25 ℃~70 ℃; Climate grade 3K22 (fixed use)

Mechanical characteristics Mechanical grade 3M11 (fixed use); Support any installation location

Connection standard wire type: Copper wire 0.2~1.5mm ² (rigid/flexible); Terminal type DFMC 1.5/4-ST-3.5 BK

The protection level of internal components for security protection is IP40; Terminal protection level IP20; Flame retardant grade UL94V-0

Installation and wiring specifications

（1） Installation requirements

All current carrying cables must pass through the core of the transformer, and protective conductors and low resistance conductor circuits must not pass through the core;

Avoid placing connecting cables (power supply, secondary connections, etc.) directly close to the transformer core to prevent interference pulses;

A conductor bending must meet the minimum distance requirement (90 ° angle distance=2 x conductor outer diameter) and be aligned with the center of the transformer;

Fixing method: M5 screws are used for CTBC20 (P)~CTBC60 (P), and M6 screws are used for CTBC120 (P)~CTBC210 (P), with tightening torques of 0.6km and 1km respectively.

（2） Wiring specifications

When multiple transformers are powered, star connections (such as through potential dividers) should be used, and daisy chain connections are prohibited;

60/75 ℃ rated copper wire must be used, with a maximum connection cable length of 10m;

Special cables are required to connect with the evaluation equipment: CTX series for RCMA420/423, CTXS series for RCMS4 series/EDS441-LAB;

Two types of surge protectors (such as Finder 7P.22.8.275.1020) need to be installed upstream of the power supply unit.

（3） Measurement range setting (applicable to CTUB101/102)

Potentiometer setting evaluation equipment response value I ∆ n effective value measurement range peak measurement range

1 ≤0.1A 0~450mA 0~900mA

2 0.1A＜I∆n≤0.5A 0~0.75A 0~3.5A

3 ＞0.5A 0~10A 0~20A

System status and LED indication

System Status Green LED Red LED Description

The device is turned off and extinguished. The device is not powered on

Normal operation, constant on/off, normal power supply, good connection between electronic module and iron core

The device has malfunctioned and is flashing. The power supply is normal, but the iron core connection is abnormal or there are other device malfunctions

Key issues

Question 1: What is the core component combination logic of the CTUB100 series? What are the differences in adaptation scenarios for different electronic modules?

Answer: The core combination logic is "electronic module+transformer core", and any electronic module can be combined with all CTBC series cores to form a complete transformer. The adaptation scenarios of different electronic modules differ as follows: ① CTUB101 (DC ± 12V): only compatible with RCMA420/423 series evaluation equipment, including T terminal, suitable for industrial circuit monitoring that requires bipolar power supply; ② CTUB102 (DC24V): compatible with RCMS4 series evaluation equipment and EDS441-LAB, can replace CTUB104, supports a maximum positioning current of 25mA, and is suitable for multi scene compatibility requirements; ③ CTUB105 (DC24V): Only compatible with RCMS4 series, with a fixed and non adjustable measurement range of 3, suitable for fixed monitoring scenarios that do not require flexible range adjustment.

Question 2: What are the special advantages of the P-type transformer core with magnetic shielding (CTBCxxP)? What are the key requirements to pay attention to during installation?

Answer: The special advantage of P-type iron core is its integrated full magnetic shielding, which is insensitive to load current and can withstand extremely high system peak load current and surge current. It is suitable for strong interference scenarios such as railway vehicles and high-power industrial equipment. Key installation requirements: ① All current carrying cables must pass through the center of the iron core completely, and it is strictly prohibited for protective conductors and low resistance conductor circuits to pass through the core; ② The minimum distance for conductor bending should be maintained (90 ° angle distance=2 x conductor outer diameter) to avoid the influence of conductor offset on measurement accuracy; ③ The connecting cables should be kept away from the iron core to prevent interference pulses, and star connections must be used for power supply to multiple devices. Chrysanthemum chains are prohibited; ④ The fixing screws should be selected according to the specifications (M5/M6), and the tightening torque should be strictly controlled at 0.6km (small size) or 1km (large size).

Question 3: How to set the measurement range of the CTUB100 series? What are the key points for matching the output signal characteristics with the evaluation equipment?

Answer: The measurement range is only supported by CTUB101/102 and can be set through potentiometers (CTUB105 fixed range 3). There are 3 options available, which should correspond to the I ∆ n response value of the evaluation device (e.g. I ∆ n ≤ 0.1A, select option 1). Output signal characteristics: The output terminals are S1 (k) and S2 (l), with a scaling ratio of 400mV/1A, a maximum output voltage of ± 10V, a maximum full-scale value of 8A, and an output resistance of 172 Ω. Matching points with evaluation equipment: ① Power supply matching: Select the corresponding electronic module (DC ± 12V/24V) according to the requirements of the evaluation equipment; ② Cable matching: Connect RCMA420/423 with CTX series cables, and connect RCMS4/EDS441-LAB with CTXS series cables, with a length not exceeding 10m; ③ Range matching: The measurement range must not be less than the I ∆ n response value of the evaluation equipment, otherwise it will reduce the measurement resolution; ④ Surge protection: Class 2 surge protectors must be installed upstream of the power supply to ensure compliance with regulatory requirements.