Mustart level 2 240 volt charger

Glad that you got it back working.. I have a Mustart 32 amp charger for about 8 months and no issues.. I did have the 26 amp version before and it worked fine but the plug overheated, so I sent it back and they sent me a 32 amp version as replacement.. Has worked fantastic ever since.. No issues. I don't plug and unplug every day.. I turn off the breaker when I'm not using it and turn it on when I need it.

 

I'm not a fan of this:

Using a circuit breaker as a switch, especially the older ones, can lead to early wear of the contacts and spring that could reduce the effective current handling. More modern ones are less likely to suffer from this kind of wear but they are pricy: https://www.mikeholt.com/mojonewsarchive/NEC-HTML/HTML/ElectricalCircuitBreakers~20020419.htm

Likewise in a parallel manner; we say that a circuit breaker can control and protect an electrical circuit. An electrical relay is an example of an operating control; it opens and closes the circuit. Circuit breakers are not designed as replacements for relays, operating controls.

There is as you may intuitively have anticipated an exception. Some circuit breakers are manufactured for use in a specific type of application. When a circuit breaker is designed to also be routinely used as an on-off switch to control 277 volt florescent luminaires they are marked SWD, for switch duty. This does not mean that a switch duty breaker can be used to manually control a traffic signal light where it will be cycled 1,000 or more times per day. The point is; the listing for switch duty (SWD) does not mean a circuit breaker can be used as a high frequency cycling operating control, such as a relay that has a life span rated in tens, if not hundreds of thousands of duty cycles.

While circuit breakers can be legitimately and safely used as switches, the frequency and duration of such use is very limited. Routinely circuit breakers are manually operated for service-maintenance, and repair type activities. With the preceding enhancing our understanding; we can say that circuit breakers can legitimately be used as switches, generally they are not intended for prolonged frequent or repetitive manual breaking and making type control of electrical energy utilization equipment.
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My experience is that the current limit of a circuit breaker tends to decrease the more often it cycles. When they trip or are switched, there is a tendency to 'arc' and that pits and oxidizes the contacts. This can lead to warmer operation and a lower current. Of course there are circuit breakers that are designed to be switches.

The safest way is to disconnect the plug from the car as this first opens the "presence" line, a no power signal line. Both the car and the EVSE will take power off safely and minimize any relay contact arcs. An equally valid approach is to command either the car or the EVSE to stop charging. Again, the power is taken off first.

GOOD LUCK!
Bob Wilson

 

I'm getting conflicting information on this. Some sources say that unplugging and plugging back in will wear the contacts and that turning the circuit breaker on and off will extend life. Now you are telling me the exact opposite.. I'm confused..

 

Breakers are $30. Plugs are $30. Does it really matter which wears out first?

I will further confuse with my own recommendation: Just leave it plugged in with the power on. Why bother shutting it off or unplugging between uses?

I own a Mustart level 2 myself. Hasn’t been unplugged or shut off since I installed it in 2018. Works great.

 

I never switch it off under load.. I have plenty of spare breakers at home too in case it goes.. As a home flipper and landlord, I'm very well stocked in electric and other supplies..

 

did you plug them in in the wrong order?
good thing you got it to work anyways.
electric golf cart chargers are like that too. plug them into the wall, then the cart.
won't work the other way.