CM-UFD.M31M grid relay: monitored quantities, interface settings and protection review
The CM-UFD.M31M is an ABB grid-interface monitoring relay intended for grid-connected generation applications. ABB product information lists a 24–240 V AC/DC control supply, 0–540 V AC measurement span, Modbus RTU and monitoring functions that include voltage, frequency, neutral-loss and vector-shift checks. Grid protection settings and approvals are jurisdiction-specific; do not treat a family datasheet as approval for every installation.
Key technical data
| Technical item | Verified value / selection note |
|---|---|
| ABB order code | 1SVR560731R3701 |
| Type designation | CM-UFD.M31M |
| Control supply | 24–240 V AC/DC |
| Measurement range | 0–540 V AC family/product data |
| Monitoring | Over/undervoltage, over/underfrequency, neutral failure, vector shift and ROCOF functions |
| Communication | Modbus RTU |
| Enclosure and terminals | IP20, screw terminals |
| Listed grid standards | VDE-AR-N 4105, 4110 and 4120; verify exact project approval scope |
The values above are intended to identify the listed version and support an initial technical review. Confirm applicable standards, rating conditions, installed accessories and the current ABB documentation for the serial number or revision before design approval, replacement or commissioning.
Application and engineering focus
Define the monitored system voltage, phase arrangement, neutral reference, grid connection point and required protection functions before selecting settings. Verify the applicable interconnection rules, utility requirements, firmware and certificate version. Thresholds, delays and reconnection logic must be engineered and approved by the responsible protection engineer. Modbus monitoring does not replace hardwired trip paths where the protection design requires them.
Configuration, compatibility and related references
Check measurement-transformer or direct-measurement arrangement, terminal assignment, communication addressing and Modbus register mapping. Confirm that the selected M31M model and certification align with the actual network code. Related CM-UFD variants can target different regulations or communication needs. Do not copy settings from M22M/M34M or another grid jurisdiction without a documented engineering review.
The related designations below are comparison references, not automatic substitutes. Confirm the complete type code, order number, interface, ratings and revision against the approved application before selecting an alternative.
- CM-UFD.M22M
- CM-UFD.M31
- CM-UFD.M34M
Installation and commissioning checks
Mount within an IP20 enclosure and observe wiring separation between measurement, control supply, trip circuits and RS-485 communications. Verify polarity, grounding, termination and bus bias for Modbus RTU. During commissioning, inject or simulate the required operating conditions under an approved test plan, confirm relay outputs and trip actions, validate event data, and seal or control protection settings according to site procedures.
During commissioning, verify the nameplate, configuration, wiring and diagnostics before enabling normal operation. Test the relevant signal path or protection response end to end under controlled conditions. Record settings and as-left measurements, and investigate abnormal values at the sensor, load, wiring or system configuration before replacing components.
Ordering, replacement and application information
For a quotation or replacement review, provide the complete designation 1SVR560731R3701,CM-UFD.M31M, ABB order code where available, serial or hardware revision, quantity, installation environment, connected equipment, interface requirements and target delivery date. Include a clear rating-label photograph and relevant wiring, loop or panel drawing when possible.
Ask the supplier to confirm the exact configuration, accessories, revision and any approved successor in writing. Do not select solely from a family name or product photograph. For safety, grid-protection, medium-voltage or regulated applications, obtain review by the responsible qualified engineer and follow local codes and the manufacturer’s instructions.
