DOLD 0060945 – MH9143.38 +/-5Hz UH AC/DC110-230V | JUAL DOLD 0060945 – MH9143.38 +/-5Hz UH AC/DC110-230V – Mains Frequency Monitor MH 9143 | Relay modules > Monitoring devices > Measuring relays / Monitoring relays > Measuring relays for main monitoring > MH 9143 > Mains Frequency Monitor > Mains Frequency Monitor MH 9143 > MH9143.38 +/-5Hz UH AC/DC110-230V