UL94 V-0 Hygrostat 65% RH Control

The MFR012 is a purpose-built electromechanical hygrostat for preventing moisture-related damage in electrical enclosures. It activates connected heaters when relative humidity exceeds 65%, effectively elevating internal dew point and eliminating condensation — the leading cause of insulation breakdown and contact corrosion in industrial control gear. Constructed from UL94 V-0 rated light grey plastic, it meets stringent fire safety requirements for use inside low-voltage cabinets and distribution boards. Measuring 67 × 50 × 38 mm, it installs effortlessly on any EN 50022 35 mm DIN rail, with full positional flexibility. The terminal block accepts up to 2.5 mm² solid core or 1.5 mm² ferruled stranded wire, with precise 0.5 Nm torque specification. Its change-over contact handles loads from micro-signalling (20 V AC/DC, 100 mA) up to heavy-duty resistive heating (250 VAC, 5 A), with 100,000 operational cycles guaranteed. Operating temperature range is 0°C to +60°C (32°F–140°F), with storage capability down to −20°C (−4°F) and up to +80°C (176°F). Switch differential is tightly controlled at 4% RH (±3% tolerance), and it functions reliably even in high-airflow environments up to 15 m/sec. EMC compliance covers EN 55014-1-2 (emissions), EN 61000-3-2 (harmonics), and EN 61000-3-3 (voltage fluctuations).