Technical Parameters
General
Product Type: Current monitoring relay (single‑phase)
Model: CM‑SRS.12S
Mounting: DIN rail (IEC 60715)
Terminal Type: Screw connection terminals
Output Contact: 1 × changeover (SPDT) contact
Contact Rating: Suitable for control and signal loads (e.g., up to ~250 V, typical industrial relay ratings)
Monitoring & Function
Monitored Current Type: AC and DC single‑phase
Detection Function: Over‑ and under‑current detection based on set thresholds
Output Contact Action: Changes state when monitored current exceeds or falls below the configured threshold
Adjustability: Threshold and hysteresis adjustable for precise current supervision
Indication: Relay output state indicates monitoring status
Coil / Supply
Control Supply Voltage: Typically supplied in variants such as 24 – 240 V AC/DC depending on version
Voltage Type: Compatible with AC/DC supply types (model dependent)
Electrical Ratings
Output Contact Capacity: Suitable for switching control circuits (e.g., up to ~4 A at 250 V AC)
Relay Contact Configuration: SPDT (Single Pole Double Throw)
Mechanical & Physical
Width: ~22.5 mm (1 module wide)
Height: ~85.6 mm
Depth: ~103.7 mm
Housing: DIN‑rail industrial enclosure
Mounting Rail: 35 mm DIN rail
Performance & Response
Response Time: Fast response to current changes (typically < 100 ms)
Hysteresis: Adjustable to prevent chattering around threshold point
Accuracy: Suitable for precise current monitoring in control systems
Environmental
Operating Ambient Temperature: Standard industrial ambient range
Pollution Degree: Industrial environments
Protection Rating: IP20 at terminal level (front/protection depends on panel installation)
Applications
Current monitoring in industrial control panels
Motor supervision and protection circuits
Alarm signalling for current thresholds
Automation control logic (PLC/relay inputs)
Detection of undercurrent / overcurrent conditions
The ABB CM‑SRS.12S is a single‑phase current monitoring relay designed for industrial control applications where precise supervision of current is required. It is intended to monitor AC and DC current in a single‑phase supply and provides an output signal via a single changeover (SPDT) contact when the monitored current crosses set thresholds. The device is mounted on a standard 35 mm DIN rail and connects with screw terminals for reliable wiring. With adjustable settings and fast response, it is used in automation systems, motor protection circuits, alarms, and control logic where accurate current monitoring and switching output are necessary.