Disconnecting Means

Location
USA
Occupation
Engineer
Article 625.43 states that a disconnect will be required for equipment rated more than 60A or more than 150V to ground. This sounds like high powered Level 2 chargers or DC fast chargers. I had a couple questions -

1. What is the purpose of having a Disconnect for EV chargers?
2. If the sub-panel that contains the EV charger's circuit breaker is within close proximity, is a separate disconnect still required?
3. What are the types of disconnecting means? Circuit breaker, Fusible disconnect, any other?
4. Some EV chargers have an emergency STOP button on their enclosures. Can those be considered as disconnects?
 

tom baker

First Chief Moderator
Staff member
1. Safety, same as why disconnects for anything. Allows us electricians to shut off the circuit
2. See definition of within sight
3. See definition of disconnecting means
4. No as it does not comply with 3 above
 
Location
USA
Occupation
Engineer
1. Safety, same as why disconnects for anything. Allows us electricians to shut off the circuit
2. See definition of within sight
3. See definition of disconnecting means
4. No as it does not comply with 3 above
1. Flipping the breaker off also disconnects power to the charger. Then why is there a separate disconnect required within sight?
2 and 3. Where can I find these definitions?
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Definitions are in article 100. Sometimes the local articles have more requirements for disconnecting means. But I think most of them require that the disconnecting means be within sight of the item. There are some exceptions where a breaker locking device can be used (e.g. some appliances in article 422) if the breaker is not within sight of the item. A cord-and-plug connection is also considered a disconnecting means.
 

tom baker

First Chief Moderator
Staff member
1. Flipping the breaker off also disconnects power to the charger. Then why is there a separate disconnect required within sight?
2 and 3. Where can I find these definitions?
1. Make it easier to service the charger as the breaker could in the basement of a building a block away, and what if the charger got run over by a reindeer, ops sorry dump truck
2/3Definitions in Art 100 of the NEC, listed first as when we know what is, we know what rules apply.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
625.43 does not require the disconnecting means to be within sight. So I believe that a breaker lock on the branch circuit breaker will suffice.

Cheers, Wayne

(2017 and 2020) 625.43 Disconnecting Means. For equipment rated more than 60 amperes or more than 150 volts to ground, the disconnecting means shall be provided and installed in a readily accessible location. The disconnecting means shall be lockable open in accordance with 110.25.
 
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