Short answer: surge arrester voltage selection should start from system voltage, grounding method, MCOV, rated voltage, nominal discharge current and insulation coordination.
| System voltage | Confirm nominal system voltage and maximum operating voltage before selecting arrester rating. |
|---|---|
| Grounding method | Solidly grounded, resistance grounded and isolated neutral systems can require different MCOV margins. |
| MCOV | MCOV must be high enough for continuous operation but low enough to protect equipment insulation. |
| Discharge current | Common classes include 5kA, 10kA and higher project-specific ratings. |
Do not choose a surge arrester only by line voltage name. MCOV and grounding method must be confirmed.
Contact sales