VL-VCM-RU(I)8S-A1(A4)(D1) — Voltage & Current Monitoring Relay, True RMS
The monitoring relay adopts a specialized chip for AC and DC sampling, allowing it to measure single-phase or three-phase voltage, frequency, and current in the power grid. It can set over- and under-limit values based on actual site conditions, ensuring the working voltage and current of terminal equipment are fully controllable. This relay is suitable for protecting electrical equipment against overvoltage, undervoltage, overcurrent, and undercurrent. It supports a wide range of operating voltages (AC/DC 24–240V), comes in a compact 18mm width for easy installation on standard 35mm DIN rails, and provides high measurement accuracy through true RMS readings. Voltage and current transformation ratios are adjustable, while real-time monitoring values are clearly displayed. The intuitive digital display and flexible function buttons make operation convenient and allow users to adjust settings as needed.
Key Features
- AC/DC sampling chip measures single- or three-phase voltage, frequency and current
- True RMS measurement for high accuracy under distorted waveforms
- Adjustable voltage/current transformation ratios with digital display
- Variants for single-phase voltage (A1), three-phase voltage (A4), AC/DC auto-detect (A/D1, AD1), single-phase current (I8S-A1) and three-phase current (I8S-A4)
- Compact 18mm width, standard 35mm DIN rail installation
Technical Specifications
| Parameter | Specification |
|---|---|
| Operating voltage | AC 24–240V (50–60Hz) / DC 24–240V |
| Setting method | Digital display, button adjustment — voltage accuracy 1, current accuracy 0.1 |
| Detection range | Voltage 24–240V (freq. 40–65Hz) · Current: single-phase 0.02–16A / three-phase 0.02–5A (extendable via external CT) |
| Limit range | ±10% (voltage 22–275V/30–275V; current 0.02–20A/0.02–6A) |
| Delay time | 0.5–29.9s (2–29.9s for AC/DC auto-detect variant) |
| Recovery value | 3–19% |
| Detection accuracy | Voltage ±1V (<100V) / ≤1% (>100V); current ≤1%; temp <0.05%/°C |
| Reset time | < 1s (2s for AC/DC auto-detect) |
| Contact rating | 10/16A, AC1-resistive |
| Electrical life | 1×10⁵ (resistive load, 1s on / 9s off) |
| Environment | Working -10 to 55°C, ≤85% RH, ≤2000m · Storage -20 to 75°C |
Applications
Protecting terminal equipment against overvoltage, undervoltage, overcurrent and undercurrent, with adjustable thresholds fitted to actual site conditions.
Downloads
Technical documentation for this product (datasheet, type-test report, CAD drawing) is being finalized and will be published here shortly. Need it sooner? Contact us via the Request a Quote form and our team will send it directly.
Packaging & Logistics
Packaging details, minimum order quantity, lead time and HS code for this product are being finalized and will be published here shortly. Need this information sooner? Contact us via the Request a Quote form.