Proving Units

For voltage indicators that have a maximum 400V test range, you need the Martindale PD430 or PD440. If your voltage indicator has a maximum 690V test range, you will need the Martindale PD690 or PD700.

Always use a proving unit that will check the full range of your voltage indicator to ensure it is working correctly.

If you have a DC specific application, the Martindale PD710 will prove up to 700V DC.