Description
Key Technical Specifications
| Parameter | Value |
|---|---|
| Manufacturer | DEIF |
| Model | RMV-112D |
| Product Type | Undervoltage / Overvoltage Protection Relay |
| Series | Uni-Line |
| Protection Functions | Undervoltage (U<) and Overvoltage (U>) |
| ANSI Protection Codes | 27 / 59 |
| Measurement Type | Three-phase RMS voltage measurement |
| Measured System | Three-phase AC networks |
| Voltage Setting Range | U> 100–120% / U< 80–100% of nominal voltage |
| Auxiliary Supply | 24VDC |
| Power Consumption | Approx. 3.5VA / 2W |
| Trip Delay | Adjustable time-controlled tripping |
| Relay Outputs | Configurable normally energized/de-energized contacts |
| Contact Rating | Up to 250VAC / 8A, 24VDC / 8A |
| Mounting | 35mm DIN rail or panel mounting |
| Weight | Approx. 0.65kg |
| Protection Application | Generator, motor, transformer voltage supervision |
Product Introduction
DEIF RMV-112D Overview
The DEIF RMV-112D is a Uni-Line protective voltage relay designed for monitoring three-phase electrical systems and protecting generators, motors, and transformers against abnormal voltage conditions. It measures RMS voltage values and provides relay outputs when undervoltage or overvoltage limits are exceeded.
The DEIF RMV-112D is used in power distribution and generator control applications where reliable voltage supervision is required. Adjustable thresholds, delay settings, and DIN rail installation make it suitable for retrofit protection panels and legacy power control systems.
RMV-112D
Application Scenarios & Field Pitfalls (The Engineer’s Perspective)
Engineering Pain Point
A generator starts normally, but connected equipment trips during operation because the bus voltage is unstable. Technicians often check the generator controller first, while the actual issue may be a voltage protection relay detecting abnormal supply conditions.
The RMV-112D operates as part of the protection chain. It does not regulate voltage. It monitors the electrical condition and sends a trip or alarm command when limits are exceeded.
Typical Applications
- Power Generation Plants – Generator output voltage supervision and protection against abnormal operating conditions.
- Marine Power Systems – Shipboard generator protection and distribution monitoring.
- Industrial Facilities – Motor feeder voltage monitoring and transformer protection.
- Utility Distribution Systems – Three-phase supply supervision for critical equipment.
Technical Pitfalls to Avoid
- Confirm Nominal Voltage Configuration
The RMV-112D uses configurable voltage modules and settings. Verify the installed module rating matches the actual electrical system voltage before commissioning.
- Check Relay Logic Configuration
Output contacts can be configured as normally energized or normally de-energized. Incorrect interpretation can cause unwanted trips or failed protection actions.
- Verify Time Delay Settings
Short voltage disturbances and true faults must be separated correctly. Incorrect delay adjustment may cause nuisance shutdowns or delayed protection response.
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