ROBERT via EV wrote:
I ask again.  Is it a relay or a contactor?  And before you answer, remember
that a relay is tested to a different set of requirements than a contactor.

The problem with a solid state relay is not the failure mode but the fact
that a solid state device always has some level of leakage current.  In other
words, a SSD cannot provide complete isolation from a source.  Have you every
seen a UL listed (UL489) solid state branch circuit protection device?

Contactors are basically larger, more powerful versions of relays. You're right; they are often tested to different standards, because of the power level and consequences of failure can be more drastic.

A 120vac EVSE could use a relay. I have two, and they both use small inexpensive relays.

A 240vac EVSE is higher power, and almost certainly would use a contactor. I have one EVSE, and it has a contactor.

No way would I trust a solid-state relay for a safety disconnect!
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