Analog AC line monitoring box

This is a quick post about our newly constructed AC line monitoring unit. This unit consists with analog AC voltmeter, frequency meter and ammeter. Both voltmeter and frequency meter are 2.5 × 2.5 inch in size and ammeter is 3.5 × 3.5 inch in size. All these panel meters are commonly available in market. Ammeter in this assembly is connected to the mains line through 60A – 5A current transformer and all the other panel meters are coupled to the mains line through 100mA quick blow fuses. Wiring diagram of this unit is illustrated in below.

Wiring diagram of analog AC line monitoring box

Enclosure of this assembly is made with medium density plywood sheets. All the internal mains line of this unit is wired using 2 × 12SWG copper wires.

We construct this unit to monitor the AC line status continuously and also to get some line measurements accurately (from known reference level). In our version of line monitor all the AC line connectors can withstand maximum of 20A because we don't have any idea / plans to do our experiments beyond 20A.

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