The Voltage Protection Rating (VPR) is a measurement of clamping voltage that is adjusted to round up to a predefined table of standardized values. It represents the average limiting voltage of a Surge Protective Device (SPD) when exposed to a surge generated by a 6 kV, 3 kA 8/20 µs combination waveform generator. VPR serves as a standardized system for straightforward comparisons of similar SPDs of the same type and voltage. Common VPR ratings include 330, 400, 500, 600, 700, and so on.

What is a Good Voltage Protection Rating?

VPR or Voltage Protection Rating of a surge protector indicates its clamping voltage, which is the highest voltage that allows passing through before limiting additional voltage. A lower rating indicates better protection and the minimum clamping voltage rating is set at 330 volts.

Also Read: Does a Surge Protector Protect Against Lightning?

What is the Difference between VPR and MCOV?

Maximum Continuous Operating Voltage (MCOV) denotes the maximum voltage allowable per mode for the device. In contrast, the Voltage Protection Rating measures the limiting voltage after a surge occurrence.

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