Residual current monitor type b with integrated measuring current transformers for earthed ac/dc systems (tn and tt systems) for comtraxx 2.1, option c (36 pages)
Ac/dc sensitive residual current monitoring module for measuring ac and dc currents up to ±100 ma (13 pages)
Summary of Contents for Bender LINETRAXX SmartDetect RCMS425-L
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LINETRAXX® SmartDetect RCMS425-L Four-channel residual current monitor sensitive to AC, pulsed DC, and smooth DC RCMS425-L_D00487_00_M_XXEN/05.2025...
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Indication of important instructions and information...............6 Service and Support............................6 Training courses and seminars........................6 Delivery conditions............................6 Inspection, transport and storage......................7 Warranty and liability.............................7 Disposal of Bender devices..........................7 Safety..................................8 Device features......................... 9 Function........................... 10 Intended Use..............................10 Functional description..........................10 3.2.1 Overview................................
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Table of contents 4.3.2 Supply voltage U ............................20 4.3.3 Wiring diagram...............................21 4.3.4 RS-485 interface............................. 22 4.3.5 Relay................................... 22 Interfaces......................... 24 NFC (Near Field Communication)......................24 Digital inputs and outputs (overview)....................24 Digital input and output Q........................24 5.3.1 Input................................... 25 5.3.2 Output................................
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LINETRAXX® SmartDetect RCMS425-L 7.10 Registers of input/output "Q"........................50 7.11 Registers of output "M+"..........................51 7.12 Registers of response-value parameters....................53 7.13 Function and operating-characteristics registers................54 7.14 Alarm-behaviour registers......................... 55 7.15 Time-behaviour registers........................... 56 7.16 Monitoring-functions registers........................ 56 7.17 Measuring-current-transformer registers.....................57 7.18 Device-error-code registers........................
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Regular face-to-face or online seminars for customers and other interested parties: www.bender.de > know-how > seminars. Delivery conditions The conditions of sale and delivery set out by Bender GmbH & Co. KG apply. These can be obtained in printed or electronic format. RCMS425-L_D00487_00_M_XXEN/05.2025...
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Bender GmbH & Co. KG is registered in the waste from electrical and electronic equipment (WEEE) register under the WEEE number: DE 43 124 402. For more information on the disposal of Bender devices, refer to www.bender.de > service & support.
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General information Safety If the device is used outside the Federal Republic of Germany, the applicable local standards and regulations must be complied with. In Europe, the European standard EN 50110 applies. DANGER Risk of fatal injury due to electric shock! Touching live parts of the system carries the risk of: •...
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• Device status and Alarm LEDs • Fault-memory behaviour selectable • RS-485 with Modbus RTU • NFC interface for device parameter setting via Bender Connect App with the device energised or de- energised • Continuous CT-connection monitoring • Sealable transparent cover (optional) •...
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Function Function Intended Use The device combination, consisting of RCMS425-L and the measuring current transformers intended for it, is designed for AC, DC and pulse-sensitive differential current measurement in TN, TT and IT systems. An RCMS425-L sounds an alarm when the adjustable response values are violated. Please note that, depending on the type of current, further function modules (in particular function module B) must be enabled and activated.
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LINETRAXX® SmartDetect RCMS425-L LEDs Ch1…4 Figure 3-1: Timing diagram 3.2.2 Connection monitoring The connections to the measuring current transformers are permanently monitored. In the event of a fault, a message is output via the interfaces and the status LED and the channel LED of the faulty connection flash yellow.
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Function 3.2.5 Alarm assignments to the alarm relay The messages • Test • Device error • Prewarning • CT connection fault • Response value main alarm I Δn can be assigned to the alarm relays K1 and K2 via the device interface. 3.2.6 Delay times t , t, t...
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LINETRAXX® SmartDetect RCMS425-L The monitoring modes available are overcurrent, undercurrent and window. • The overcurrent mode checks whether the measured value exceeds a response value. • The undercurrent mode checks whether the measured value falls below a response value. • The window discriminator mode checks whether the measured value is within a range. Lower limit: response value of the pre-warning Upper limit: response value of the main alarm Undercurrent mode...
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Function Parameter Adjustable per channel Modbus register Delay on release t 32910…32916 Type of measuring current 33100…33103 transformer 3.2.8 Automatic measuring range switching The RCMS425-L device measures at least 5 times the set residual operating current (5 x I Δn However, once (5 x I ) is reached, no measured value is displayed;...
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LINETRAXX® SmartDetect RCMS425-L 3.2.10 Combined function button (T/R button) Reset = pressing the T/R button 1…3 s Test = pressing the T/R button 3…6 s NFC = pressing the T/R button 6…10 s Addr. = pressing the T/R button 10…15 s 3.2.11 Fault memory The storing of a fault in the memory can be enabled or disabled.
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3.2.15 NFC interface The NFC interface can be used to transmit a previously configured device parameter setting directly to the device. This function is available only via the Bender Connect App. You can find this app in the Appstores for and Android.
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Function module C: Connection of Type A external current transformers Function module C permits the use of measuring-current transformers by manufacturers other than Bender. When an external current transformer is used, a number of turns must be selected in the corresponding Modbus register (33104…33107).
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Dimensions, mounting and connection Dimensions, mounting and connection Only skilled persons are permitted to carry out the work necessary to install, put into service and run a device or system. DANGER Risk of fatal injury due to electric shock! Touching live parts of the system carries the risk of: •...
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Dimensions, mounting and connection Bottom Terminal Description 21, 24, 22 Relay K2 Digital input Multifunctional output Digital input/output ON (R) Termination of RS-485 interface A, B RS-485 interface: Modbus RTU +, - Supply voltage DC 4.3.2 Supply voltage U The device has two separate supply voltage connections US (A1, A2 and +, -). The technical data must be observed.
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LINETRAXX® SmartDetect RCMS425-L 4.3.3 Wiring diagram AC/DC 100…240 V DC 24 V Back-up fuse for U : 6 A RCMS425-L and all connected CTUB102-CTBCxx devices must be supplied from the same power supply. For UL applications: The measuring current transformers must be connected before operation. Cable lengths to the measuring current transformer: See technical data.
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Specification The RCMS425-L has an RS-485 interface with Modbus RTU protocol. In a system setup it is therefore compatible with other Modbus RTU-capable device series from Bender, such as e. g. the RCMB300 series, RCMS150-01, and RCMB13…-01. Up to 247 Modbus-RTU devices can be used on the bus.
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LINETRAXX® SmartDetect RCMS425-L Function State Description The relay switches if a measuring current transformer CT connection fault on | off connection fault exists ADVICE Attention! High contact currents damage the hard gold plating of the relay contacts. Damaged contacts prevent the relay from switching correctly at low contact currents. RCMS425-L_D00487_00_M_XXEN/05.2025...
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NFC (Near Field Communication) The NFC interface can be used to transmit a previously configured device parameter setting directly to the device. This function is available only via the Bender Connect App. You can find this app in the Appstores for and Android.
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LINETRAXX® SmartDetect RCMS425-L The output becomes active if AL1 of the selected measuring channel Prewarning (AL1) AC/DC/RMS CH1…4 is present. The output becomes active if AL2 of the selected measuring channel Main alarm (AL2) AC/DC/RMS CH1…4 is present. The output becomes active if a CT-connection fault (short circuit or CT-connection fault CH1…4 interruption) of the selected measuring channel is present.
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Interfaces Low-active: In the active mode the GND potential is applied to output Q. In the passive mode an external voltage can be connected (see Technical data). The output switches the applied potential to GND. internally externally Permanently high: The output is permanently set to +24 V.
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LINETRAXX® SmartDetect RCMS425-L 5.4.1 Digital mode Settings in registers 32500…32501 In digital mode, M+ can be operated in Active, Passive or Permanent mode. The following settings can be assigned: M+ = Active High-active: In the active mode +24 V are applied to output M+ internally. Low-active: In the active mode the GND potential is applied to output M+.
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Interfaces M+ = Permanently low The output is permanently switched to GND. In this manner e. g. an additional reference for the digital input can be created. Alarm assignments permit assigning the following alarms to the output M+ in digital mode (registers 32504… 32519): The output becomes active if AL1 of the selected Prewarning (AL1) AC/DC/RMS CH1…4...
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LINETRAXX® SmartDetect RCMS425-L 50 % ≥ 100 % I or set Δn RMS full scale value 0…20 mA 10 mA 20 mA 0…10 V 10 V 50 % 4…20 mA 4 m A 12 mA 20 mA 2…10 V 10 V Explanation to in the diagram: In the 4…20 mA or 2…10 V mode an output value of 0 mA or 0 V is a sign of a wiring fault of the analogue...
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Interfaces The response delay and the delay on release of the digital input are set to 100 ms each. Input CT 5.6.1 Wiring of measuring current transformer type A/type F S2(l) S1(k ) S1(k)S2(l) Measuring current transformers "Type A/Type F" CAUTION High-frequency residual currents (>10 kHz) through any connected residual current transformer can cause crosstalk on all channels to which a CTUB102-...
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LINETRAXX® SmartDetect RCMS425-L 5.6.2 Wiring of measuring current transformer type B/B+ * = RCMS… 5.6.3 Suitable measuring current transformers Type B/Type B+ Type A/Type F Type A Series Series CTBS Series CTUB Series CTAC Series WR Series WS CTAS WR70x175S WS20x30 CTAS50 W0-S20...
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The device has an RS-485 interface with Modbus RTU protocol. In a system setup it is therefore compatible with other Modbus RTU-capable device series from Bender, such as e. g. the RCMB300 series, RCMS150-01, and RCMB13…-01. Up to 247 Modbus-RTU devices can be used on the bus.
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LINETRAXX® SmartDetect RCMS425-L Termination The bus line must be terminated at both ends with resistors (120 , > 0.25 W). A terminating resistor is installed in the device and can be enabled or disabled with the DIP switch at the underside of the housing.
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Operation and settings on the device Operation and settings on the device Control panel Control panel Meaning STATUS LED Operating mode ALARM 1 ALARM LED Pre-warning ALARM 2 ALARM LED Main alarm Ch 1…4 CHANNEL DISPLAY LEDs 1…4 Test/reset button STATUS LED Multicoloured display of various operating modes.
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LINETRAXX® SmartDetect RCMS425-L ALARM LEDs Display of prewarning AL1 and main alarm AL2 Operating state PRE-WARNING ALARM1 Lights up continuously when the pre-warning threshold has been exceeded on a channel. MAIN ALARM ALARM2 Flashes when the residual-operating-current threshold I has been Δn exceeded on a channel.
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Operation and settings on the device "RESET" function The "RESET" function on the button resets stored alarm states. "TEST" function The "TEST" function simulates a residual current of 1.5 x I for a period of 5 seconds. During this period, the Δn device has the following states: •...
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LINETRAXX® SmartDetect RCMS425-L Addresses can only be entered within the valid address range. When there is no input for a period of 5 minutes, the device automatically exits the address setting mode. The device then uses the currently set Modbus address.
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Modbus interface Modbus interface Overview The following Modbus function codes are supported: • Holding registers for reading out values (Read Holding Register; function code 0x03) • Registers for device programming (Write Multiple Registers; function code 0x10) For a complete Modbus-protocol specification, visit http://www.modbus.org. Read and write permissions Read Only (read access only) Read/Write (read and write access)
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UTF8 String Article number e.g.: B74604040 UTF8 String Serial number 10 digits, e.g.: 2002123456 UTF8 String Manufacturer Bender GmbH & Co. KG UTF8 Application D number UINT16 631 = D631 Application version UINT16 xxx = Vx.xx number Application build UINT16...
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Modbus interface Alarm/measuring value registers Measured values (registers 999…1999) Prop- Register Description Format Bytes Values / Unit / Comment erty 0…n = number of active messages (device error, alarms, Number of active connection faults, …) UINT16 messages n is the number of messages that could also be attributed to an output (e.
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LINETRAXX® SmartDetect RCMS425-L Prop- Register Description Format Bytes Values / Unit / Comment erty 1072 AC CH1 Float 1074 AC CH2 Float 1076 AC CH3 Float 1078 AC CH4 Float 1080 DC CH1 Float Residual current 1082 DC CH2 Float measured Smallest measured value since the last Modbus query 1084...
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Modbus interface Prop- Register Description Format Bytes Values / Unit / Comment erty Status Reload 2014 memory Input/output UINT16 0 = Reload memory inactive "Q" 1 = Reload memory active Status Reload 2015 UINT16 memory Output "M+" Status information registers Status information (registers 3000…3999) Prop- Register...
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Modbus interface Prop- Register Description Format Bytes Values / Unit / Comment erty THD (Total Harmonic Distortion) 5084 THD CH1 UINT16 THD channel 1 Validity of the THD value 5085 THD validity CH1 UINT16 0: = 2: > 5086 THD CH2 UINT16 THD channel 2 Validity of the THD value...
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LINETRAXX® SmartDetect RCMS425-L Prop- Register Description Format Bytes Values / Unit / Comment erty Full spectrum (H1…H400) THD: Square root of the sum of the squares of the harmonics H1…400 (excluding fundamental) divided by the fundamental; 5601 Full spectrum THD UINT16 range of values 0…10,000 [%] Validity of the THD value...
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LINETRAXX® SmartDetect RCMS425-L Prop- Device Register Description Format Bytes Value/Unit/Comment Reversible erty faulty 486 =invalid setting of CT4: AC response value < 10 mA or > 10 A 58025 4.86 UINT16 with a "type B" measuring-current transformer 58026 6.00 UINT16 600 = internal error 58027 6.10...
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Modbus interface 7.19 Control-commands registers Control commands (59000) Prop- Factory Register Description Format Bytes Values / Unit / Comment erty setting 0 = disabled 59000 UINT16 1 = enabled (automatic disabling after 5 min) 59001 Test Relay K1 UINT16 0 = Switch off relay (automatic return to normal operating mode after 60 s) 1 = Switch on relay (automatic return to normal 59002...
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LINETRAXX® SmartDetect RCMS425-L Prop- Register Description Format Bytes Value/Unit/Comment erty 60003 Modbus address UINT16 0…247 = new Modbus address Function 2: Find device 60000 Function selection UINT16 2 = Selection of the "Find device" function 61918 60001 Pattern value part 1 UINT16 Security pattern must be written for the function to be executed.
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Error – Cause – Error correction Error – Cause – Error correction Error pattern Cause Correction Complete device Terminal blocks incorrectly plugged in Plug in terminal blocks correctly. No device start Supply voltage incorrectly connected Establish correct wiring. RS-485 Missing termination due to incorrect Configure the terminating resistor, commissioning or defective component.
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LINETRAXX® SmartDetect RCMS425-L Technical data Frequency responses of the filters The curves represent the area in which the device triggers a main alarm. The frequency range below 15 Hz is not defined. RCMS425-L_D00487_00_M_XXEN/05.2025...
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Technical data RCMS425-L_D00487_00_M_XXEN/05.2025...
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LINETRAXX® SmartDetect RCMS425-L Tabular data ()* = Factory setting Insulation coordination (IEC 60664-1/ IEC 60664-3) Definitions Supply circuit (IC1) A1, A2 Measuring circuit (IC2) +, –, A, B, M+, Q, I, GND, CT1…4 Control circuit (IC3) 11, 12, 14 Control circuit (IC4) 21, 22, 24 Rated voltage 250 V...
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Technical data Supply voltage (+, -) Connection +, – Supply voltage U DC 24 V Protection class of power supply unit 2 or 3 Permissible tolerance –30…+25 % Permissible ripple Power consumption ≤ 2 W Inrush current (< 5 ms) <...
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LINETRAXX® SmartDetect RCMS425-L Hysteresis 10…25 % (15 %)* Fault-memory alarm messages on/off (on)* Permissible continuous residual current with single-channel use 85 A dual-channel use 60 A use of three channels 49 A use of four channels 42 A The requirements of the respective standards are only met with a response value from 30 mA to 9.9 A. Measuring-current transformers Connection CT1…4 (S1, S2)
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Technical data Time response Start-up delay t 0…999 s (0 s)* Response delay t 0…10 s (0 s)* Delay on release t 0…999 s (1 s)* Operating time t with 1 x I ≤ 260 ms Δn with 5 x I 40…100 ms Δn Response time t...
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LINETRAXX® SmartDetect RCMS425-L Input I Connection Max. cable length (recommended) 10 m External connections Potential-free contact Input/output Q Connection Max. cable length (recommended) 10 m Max. load 20 mA Low voltage level (output) 0…2 V High voltage level (output) 10 V…U External voltage (passive mode) DC 0…(U - 1 V)
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Technical data Connections (A1, A2, relays) Terminals Plug-in screw-type terminals Terminal series Phoenix Contact MSTBT 2,5/…-ST-5,08 BK Connection properties Rigid 0.2…2.5 mm² Flexible, without plastic sleeve 0.25…2.5 mm² Flexible, with plastic sleeve 0.25…2.5 mm² Stripping length 7 mm Tightening torque 0.5…0.6 Nm Conductor cross section AWG 24…12...
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Declaration regarding the radio system EU declaration of conformity Bender GmbH & Co. KG hereby declares that the device covered by the Radio Equipment Directive complies with Directive 2014/53/EU. The full text of the EU Declaration of Conformity is available at the following...
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Technical data Ordering information Measuring current transformers that can be used Supply Configurable Enabled function Type Art. No. voltage U at the factory modules * Type A Type B Type F Type B+ In preparation: Customised with function In preparation ex factory B84605040 module B...
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