Issue
Various controller install guides suggest fitment of an optional varistor for surge/spike protection, what components should be used?
Product Line
Andover Continuum
Environment
- Surge and transient protection
- Metal Oxide Varistors (MOV) Part Number
- Line voltage protection, power line protection, mains spike protection.
- Noise, EMC resilience.
Cause
Install guides specify 39V, 130V or 250V varistors but what component part numbers should be used?
Resolution
For controllers with a 24VAC power feed, these are specified as a 39V Varistor, a suitable component would be: V39ZA1 This is also equivalent to Part # 01-2020-095 as listed in some install guides.
For controllers fed from a 115VAC power feed, these are specified as a 130V Varistor, a suitable component would be: V130LA20A
For controllers fed from a 230VAC power feed, these are specified as a 250V Varistor, a suitable component would be: V250LA40A
Littelfuse Varistor ZA Datasheet PDF showing the full specification for each varistors is attached.
