Charger circuit breaker flips after a minute or two of charging

[shadowman]

it is possible its just a C.B best way to find out try the charger on another cart see if does the same thing if so replace it.......if not check wiring in cart...........................

[808Pants]

I coulda started this thread yesterday, though it's 7 years old now...having recently bought a cart I worked on a few years ago (now sorting through the neglect), I was in the process of writing up my bafflement at the 15A charger breaker tripping when the ammeter shows way less, wondering whether the 20A-scale on the meter made sense ever, considering that 15A breaker... and then clapped myself on the forehead, because I'd realized the circuit-breaker in the charger is on the primary (AC input) side of the transformer, not the charging/DC side. There isn't anything like a 1:1 relationship between AC input and the metered charging current, though I expect an EE might post a rough formula if we wanted to nerd out on this...something like

In the case of my charger, I put a clamp-on ammeter on one AC lead (at the transformer input, where the line-cord splits within the case), and found that it was consuming about 9A, at the same time as the DC charging current was around 18A.

And yep, that means the 15A breaker shouldn't have been chronically tripping (should not even at 20A charging current).

Until my replacement ebay breaker arrives, I've just bypassed the panel-mount breaker and am relying on a 15A power-strip breaker. An AC ammeter for the charger might be on my list of things to do...but I guess it'd be pretty far down the list.

[greg-g]

Originally Posted by 808Pants

I coulda started this thread yesterday, though it's 7 years old now...having recently bought a cart I worked on a few years ago (now sorting through the neglect), I was in the process of writing up my bafflement at the 15A charger breaker tripping when the ammeter shows way less, wondering whether the 20A-scale on the meter made sense ever, considering that 15A breaker... and then clapped myself on the forehead, because I'd realized the circuit-breaker in the charger is on the primary (AC input) side of the transformer, not the charging/DC side. There isn't anything like a 1:1 relationship between AC input and the metered charging current, though I expect an EE might post a rough formula if we wanted to nerd out on this...something like

In the case of my charger, I put a clamp-on ammeter on one AC lead (at the transformer input, where the line-cord splits within the case), and found that it was consuming about 9A, at the same time as the DC charging current was around 18A.

And yep, that means the 15A breaker shouldn't have been chronically tripping (should not even at 20A charging current).

Until my replacement ebay breaker arrives, I've just bypassed the panel-mount breaker and am relying on a 15A power-strip breaker. An AC ammeter for the charger might be on my list of things to do...but I guess it'd be pretty far down the list.

I would disconnect the charger NOW replace both the diodes and breaker.

primary vs secondary
take the primary amps per clamp on multiply by volts 110-120 and get watts
take the secondary amps per gauge multiply by volts 48-60 and get watts now compare the watts reading.

[Volt_Ampere]

I have had several of this type of circuit breaker fail this way. You will have to replace it or you could change it to a fuse. Fuses tend to be much more reliable than circuit breakers.

[808Pants]

Originally Posted by greg-g

I would disconnect the charger NOW replace both the diodes and breaker.

primary vs secondary
take the primary amps per clamp on multiply by volts 110-120 and get watts
take the secondary amps per gauge multiply by volts 48-60 and get watts now compare the watts reading.

Why mess with diodes?

Your watt-conversion seems reasonable, assuming power-factor of around 1, and would square with the charging current I was seeing. OTOH, the breaker is clearly tripping at about half its rating, ergo trashed. And my temp power-strip setup has a similarly-cheesy breaker that pops regularly if I look at it wrong, so...I don't see the need to stop charging.

--Dave