Residual current monitoring system LINETRAXX® RCMS490-L

transformercontinuousdigital

Overview
The LINETRAXX® RCMS490-L is a multichannel residual current monitor for detecting and evaluating fault, residual and operating currents in earthed power supplies. Each device provides 12 measuring channels and the RCMS490 variant offers one alarm contact per channel. Systems can be expanded via BMS bus (RS-485) to monitor large numbers of sub-circuits.

Key capabilities

• Selectable measurement sensitivity per channel: AC (Type A), pulsating DC or AC/DC sensitive (Type B) depending on the measuring current transformer
• Alternative to insulation testing during periodic verification
• Per-channel alarm (RCMS490) or device alarm relays
• Analysis of harmonics, DC components and THD
• Adjustable frequency response for fire protection and plant protection

System and measuring current transformers
Measuring current transformers (CT) relevant for each measurement type: closed CTBS25 or CTUB100 series for AC/DC sensitive (Type B, require 24 V DC supply); CTAC (closed), WR (rectangular), WS (split-core) and WF (flexible) series for AC and pulsating currents (Type A). Any combination of CT series may be connected to device channels. Up to 90 RCMS devices can be linked via BMS bus (RS-485 with BMS protocol), enabling monitoring of up to 1,080 channels in one system.

Features

• True r.m.s. value measurement
• 12 measuring channels per device (residual current measurement or digital input)
• Fast parallel scanning for all channels
• Response ranges examples: 10 mA…10 A (0…2000 Hz); 6 mA…20 A (42…2000 Hz); 100 mA…125 A (42…2000 Hz) for certain variants
• Preset function and adjustable time delays
• History memory with date/time stamp (300 records) and data logger (300 records per channel)
• Continuous CT connection monitoring; password protection for settings
• Backlit graphical display and alarm LEDs

Applications

• Monitoring and evaluation of residual, fault and operating currents across wide frequency ranges (0…2000 Hz or 42…2000 Hz depending on CT)
• Fire-hazard current detection and fast disconnection for fire protection
• EMC monitoring in TN-S systems for stray currents and additional N-PE connections
• Monitoring neutral conductors for overload due to harmonics
• Verification of PE and equipotential bonding conductors to ensure they are free of current
• Residual current monitoring of fixed electrical equipment to determine practical test intervals (e.g., DGUV V3)
• Monitoring digital inputs

Variants
Type | Supply voltage U_S | Art. No.
RCMS490-L-1 | DC 16…94 V / AC 16…72 V, 42…460 Hz | B94053007
RCMS490-L-2 | DC 70…276 V / AC 70…276 V, 42…460 Hz | B94053008

Optional accessories (selection)
Power supplies
STEP-PS/1 AC/24 DC/0.5 (for up to 4 CTUB100) | B94053110
STEP-PS/1 AC/24 DC/1.75 (for up to 14 CTUB100) | B94053111
STEP-PS/1 AC/24 DC/4.2 (for up to 34 CTUB100) | B94053112
DI-1PSM (RS-485 repeater) | B95012044

Repeaters and interface converters (examples)
COM465IP | Condition Monitor with integrated gateway (Bender/Ethernet) | B95061065
CP907-I / CP915-I | Condition Monitor for connection of BMS devices to TCP/IP networks | B95061031 / B95061032 / B95061033 / B95061034

Measuring current transformers (selection)
Pulsating-current sensitive examples: CTAC20 (ø20) B98110005; CTAC35 (ø35) B98110007; WR70x175S (70x175) B11738; WS20x30 (split-core) B98080601.
AC/DC sensitive examples: CTUB102-CTBC20 (ø20) B78120011; CTBS25 (ø25) B98120060.

Downloads (selected)
Datasheets, manuals, CE/UKCA declarations and technical addenda are available for the RCMS460/RCMS490 product family.

Technical specifications

• Product family: LINETRAXX® RCMS (RCMS490-L device variant)
• Measuring channels per device: 12
• Expandable via BMS bus (RS-485) up to 90 monitors / 1,080 channels
• Measurement types: AC, pulsating DC, AC/DC sensitive (dependent on CT series)
• Response frequency ranges: 0…2000 Hz and 42…2000 Hz (depending on CT)
• Response ranges (examples): 10 mA…10 A; 6 mA…20 A; 100 mA…125 A for certain variants
• Alarms: per-channel alarm (RCMS490) or device alarm relays
• History memory and data logger: 300 records
• Interfaces: BMS bus (RS-485); gateways available for Ethernet/Modbus/SNMP
• User interface: Backlit graphical display and alarm LEDs
• Protection/configuration: Adjustable frequency response and time delays; password protection; continuous CT connection monitoring
• Standards/compliance: CE and UKCA documentation available