Proving unit for use with electrical test tools

A proving unit to verify the operation of a separate voltage measurement device, the proving unit comprising:

• an alternating current (AC) voltage source that, in operation, provides an AC voltage at an AC output node;
• a contact AC/DC positive port;
• AC-to-DC converter circuitry that, in operation, receives an AC voltage as input and outputs a DC voltage;
• at least one AC/DC switch that, in operation, selectively electrically couples the AC-to-DC converter circuitry between the AC output node and the contact AC/DC positive port;
• a field sense conductor electrically coupled to the AC output node;
• a mode selection switch;
• and
• control circuitry operatively coupled to the mode selection switch, the AC voltage source, and the at least one AC/DC switch, wherein, in operation, the control circuitry:
• receives, via the mode selection switch, a selection of a mode of operation, the mode of operation comprising at least a DC voltage mode or an AC voltage mode;
• controls the at least one AC/DC switch based at least in part on the received selection of a mode of operation;
• and
• causes the AC voltage source to provide an AC voltage at the AC output node.

A kit, comprising:

• a voltage measurement device;
• and
• a proving unit to verify the operation of the voltage measurement device, the proving unit comprising:
• a housing;
• an alternating current (AC) voltage source that, in operation, provides an AC voltage at an AC output node;
• a contact AC/DC positive port that is accessible to a test instrument probe of a separate contact voltage measurement device;
• AC-to-DC converter circuitry that, in operation, receives an AC voltage as input and outputs a DC voltage;
• at least one AC/DC switch that, in operation, selectively electrically couples the AC output node of the AC voltage source either directly to the contact AC/DC positive port, or indirectly to the contact AC/DC positive port via the AC-to-DC converter circuitry;
• a field sense conductor disposed within the housing at a sensor receiving portion of the housing, the sensor receiving portion configured and arranged to receive at least a portion of the voltage measurement device, the field sense conductor electrically coupled to the AC output node;
• a mode selection switch;
• and
• a controller operatively coupled to the mode selection switch, the AC voltage source, and the at least one AC/DC switch, wherein, in operation, the controller:
• receives, via the mode selection switch, a selection of a mode of operation, the mode of operation comprising at least a DC voltage mode or an AC voltage mode;
• controls the at least one AC/DC switch based at least in part on the received selection of the mode of operation;
• and
• causes the AC voltage source to provide an AC voltage at the AC output node.