Home Power Factor & Frequency Relays Monitored frequency range - 48 - 72 Hz Power Factor & Frequency Monitoring Relays - Monitored frequency range - 48 - 72 Hz Filters and sorting Cancel the filter Recommended Bestsellers Cheapest Most expensive -25% Quick info HRF-10 Hlídací relé frekvence In stock £ 34.20 excl. VAT £ 45.60 Add to cart Share Tweet Pin It