EPRO RSM020 Relay Output Module

The EPRO RSM020 is a compact, dual-channel relay module designed to provide alarm and trip functions based on analog input signals from sensors or conditioners. It accepts standard industrial inputs such as 4-20 mA current loops or voltage signals (0-10 V, ±10 V) and compares them against user-adjustable setpoints. Each channel has two independent relays (typically one for alarm, one for danger/trip) with adjustable hysteresis and time delays. The RSM020 is widely used in machinery protection systems to trigger alerts or automatic shutdowns when vibration, displacement, temperature, or other parameters exceed safe limits.

Key Features

• Dual Independent Channels: Each channel can monitor a separate input and control its own set of relays.

• Adjustable Setpoints: Front-panel potentiometers or DIP switches allow easy adjustment of trip levels without software.

• Adjustable Hysteresis: Prevents relay chatter near the setpoint by defining a reset band.

• Time Delay: Programmable on-delay and off-delay to avoid nuisance trips during transient events.

• Relay Outputs: SPDT or DPDT relays rated for 250 VAC / 5 A, suitable for direct control of alarms, annunciators, or PLC inputs.

• Input Isolation: Galvanic isolation between input channels and output relays protects against ground loops.

Technical Specifications

• Input Signals: 4-20 mA, 0-10 V, ±10 V (selectable per channel)

• Input Impedance: 50 Ω for current, >100 kΩ for voltage

• Accuracy: ±0.5% of full scale

• Setpoint Range: 0-100% of input span

• Hysteresis: 0-20% of span (adjustable)

• Time Delay: 0-10 seconds (adjustable)

• Relay Contacts: 2 per channel, SPDT, 250 VAC / 5 A resistive

• Power Supply: 24 VDC (18-36 VDC) or 115/230 VAC (depending on variant)

• Operating Temperature: -20°C to +60°C

• Mounting: DIN rail (EN 50022)

• Certifications: CE, UL (optional)

Applications

The RSM020 is used in turbine, compressor, and pump protection systems to monitor vibration, shaft displacement, bearing temperature, and process variables. It provides hardwired relay outputs for alarm horns, warning lights, or direct shutdown of machinery via emergency stop circuits. It is also employed in test stands and industrial processes requiring threshold monitoring with relay outputs.

Integration and Configuration

Installation involves mounting the module on a DIN rail, connecting the input signal(s) and power, and wiring the relay contacts to the external devices. Setpoints and hysteresis are adjusted using the front-panel trimmers or DIP switches. Some versions offer optional communication (e.g., Modbus) for remote monitoring of setpoints and relay status.

Reliability and Environmental Compliance

Designed for demanding industrial environments, the RSM020 meets IEC 61000-4 immunity standards and is tested for vibration and temperature extremes. Its robust relay contacts ensure long life even under frequent switching. The module is RoHS compliant and CE marked.

With its simple adjustment and reliable performance, the EPRO RSM020 relay output module provides a cost-effective solution for adding hardwired alarms to any monitoring system.