1SVR740850R0300 ABB CM-ENS.31P Liquid Level Fill/Drain Monitoring Relay

Why Choose the ABB CM-ENS.31P Liquid Level Monitoring Relay?

The ABB CM-ENS.31P, order code 1SVR740850R0300, is a versatile liquid level monitoring relay designed for filling and draining control of conductive fluids in industrial tanks, vessels and pumping systems. As part of the ABB CM-ENS liquid level monitoring relay series, it can control one or two liquid levels and provides dependable protection against overflow and pump dry running.

The CM-ENS.31P offers an exceptionally wide adjustable response sensitivity range of 0.1–1000 kΩ, enabling adaptation to conductive liquids with different electrical characteristics. Fill (UP) or Drain (DOWN) operation can be selected from the front of the relay, while selectable ON- or OFF-delay functionality helps prevent unwanted switching caused by temporary level fluctuations or wave formation.

With a wide 24–240 V AC/DC rated control supply voltage, two changeover (SPDT) output contacts and ABB Easy Connect push-in terminals, the CM-ENS.31P provides flexible integration into industrial control panels. Its compact 22.5 mm DIN-rail housing, three status LEDs and adjustable front-face controls make configuration and operation straightforward.

Key Advantages

• Flexible Fill (UP) or Drain (DOWN) liquid level control.
• Wide 24–240 V AC/DC control supply supports numerous industrial control systems.
• Adjustable 0.1–1000 kΩ response sensitivity for different conductive fluids.
• Controls one or two liquid levels for minimum and maximum level supervision.
• Provides overflow and pump dry-running protection.
• Selectable ON- or OFF-delay helps prevent unwanted switching caused by liquid movement.
• Two changeover (SPDT) contacts provide flexible signalling and control outputs.
• Maintenance-free Easy Connect push-in terminals simplify panel wiring.
• Compact 22.5 mm-wide housing conserves DIN-rail space.

Key Features

• ABB CM-ENS liquid level monitoring relay series.
• 24–240 V AC/DC rated control supply voltage.
• Fill (UP) or Drain (DOWN) operation selectable via front-face control.
• Adjustable response sensitivity of 0.1–1000 kΩ.
• Control of one or two conductive liquid levels.
• Minimum and maximum level monitoring capability.
• Selectable ON- or OFF-delay function.
• Tripping delay of 0 or 0.1–30 s.
• 2 c/o (SPDT) output contacts.
• 3 LED indicators for operational status.
• High EMC immunity for dependable industrial operation.
• Cascadable design for expanded monitoring applications.
• ABB Easy Connect push-in connection technology.
• Tool-free mounting and removal from DIN rail.

Reliable Filling and Draining Control for Conductive Liquids

Liquid level monitoring relays use electrodes in the monitored vessel to detect the presence of electrically conductive liquids. The ABB CM-ENS.31P can supervise minimum and maximum levels and switch its relay outputs according to the selected Fill (UP) or Drain (DOWN) operating mode, allowing pumps, valves and associated control equipment to respond automatically.

Its adjustable 0.1–1000 kΩ sensitivity enables the measuring circuit to be matched to a wide variety of conductive fluids. Selectable timing functionality can reduce unwanted switching caused by waves or short-term level changes, making the CM-ENS.31P suitable for reliable tank management, overflow prevention and dry-running protection.

Typical Applications

• Automatic filling of tanks and vessels.
• Automatic draining and emptying systems.
• Pump dry-running protection.
• Tank overflow protection.
• Minimum and maximum liquid level alarms.
• Water and wastewater handling systems.
• Industrial process tanks containing conductive fluids.
• Pump, valve and process control panels.