Industrial VM221D Relay

The VM221D Relay is Schneider Electric’s VAMP 221 arc protection system component designed for selective arc fault protection in low- and medium-voltage power networks. It combines a central unit with modular I/O options (including VAM 12L and VAM 12LD, VAM 10L, VAM 3L, and VAM 4C/4CD/4CRL, plus the multiplying VAMP 4R) and uses a BI/O bus interface to connect multiple central units and I/O modules. The system delivers zone-based arc fault protection (50ARC) and circuit breaker failure protection (50BF), along with unbalance alarms, enabling coordinated responses across protection zones. This architecture supports tailored protection schemes for complex switchgear configurations and is suited to LV and MV installations, with documentation noting EU directive compliance.