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Discussion Starter #1
Hi! I work as an electrician in sweden and have a problem with a clients car.
It´s an Zoe from 2017 and the problem is that the car is fully charged in the morning but the fuse has blown probably when the preheater is working.

I´m using an RCBO C16A. If i try to charge in a regular socket with regular fuses and an RCD, just the fuses blows and not the RCD.

BUT! If we start the heater manually and wait for the problem, nothing happens!
 

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Pre-heat will draw a maximum of about 3kW. If you're in Sweden, then you may also have a battery heater and I'm not sure what draw that will have. It seems odd for it to trip (blow?) the fuse, do you mean breaker(?) when heating but not charging. Is the charger a 3 or 7kW? You say its on a 16A RCBO, so I'm assuming its 3kW. It may be that when the car pre-heats, it also tries to charge too and is drawing too much power from the charger? But, the charger should be telling the car what its maximum output is.

Try plugging in to charge, then pressing the pre-heat button on the keyfob to activate pre-heating when charging. Does it trip then? Is the RCBO faulty?
 

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Co-author of CanZE. Q210 nov 2013
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As per the standard, car can take (from memory) 5% more current than specified by the pilot signal in the chargepoint.

Are you 100% sure the chargepoint is set to 16A? And believe it or not, I have seen a single phase chargepoint where the sparky connected the L1, L2 and L3 wires to the single feed line :whistle: Makes sense to use a B characteristic breaker.
 

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Discussion Starter #4
Pre-heat will draw a maximum of about 3kW. If you're in Sweden, then you may also have a battery heater and I'm not sure what draw that will have. It seems odd for it to trip (blow?) the fuse, do you mean breaker(?) when heating but not charging. Is the charger a 3 or 7kW? You say its on a 16A RCBO, so I'm assuming its 3kW. It may be that when the car pre-heats, it also tries to charge too and is drawing too much power from the charger? But, the charger should be telling the car what its maximum output is.

Try plugging in to charge, then pressing the pre-heat button on the keyfob to activate pre-heating when charging. Does it trip then? Is the RCBO faulty?
Sorry for my bad english! I mean Circuit Breaker and not a fuse.

And its a three phase ciruit breaker. Thats the "normal" here so i forgot to give you that information.

The car was set to 10amp when delivered but now we have changed the setting to 13A after talking with the car dealer. So settings is lower than the capacity of the CB and the car shouldn´t be able to overload that much to trip an 16A CB.


So, just to clarify.
When used in an single phase 10A outlet on the house it trips the Circuit Breaker sometimes but never the RCD.

When used in the Three Phase outlet with an Three Phase 16A RCBO, it trips every time.

BUT! If we start the heater with the key fob there´s never any problems....

Because the car is fully charge everyday the problem must be when it´s charged and then start to heat but the car sholud shut down the charging before heating!? and also the setting is lower than the capacity
 

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Co-author of CanZE. Q210 nov 2013
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A few clarifications:
- (semantics I know): you can't set the car to 10 or 13 amps. That has to be done on the chargepoint, but I am sure that is what you meant;
- the heater (compressor) is fed through the 400 volt bus, it's not like the consumption of the car charger is matching the heater. The heater is simply fired up and at the same time the charger is activated.

Are you 100% it is not a combined circuit breaker (overload) and earth leakage device tripping? If so it is very hard to determine if it's an overload or an earth fault causing the tripping.

If you are 100% sure it's the heating, it's most probably an isolation fault in the AC compressor and thus a ground current issue, not an overload. We've seen it before. Unfortunately if that is the case that is not a cheap repair.
 

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Hi,
My charger is set to 12A three phase. (car uses 11A) The attached pdfs show the power consumption at preheat @ -1. Timer set to 0715 so it starts at about two hours before at temperatures below 0. Less if warmer about one hour. R90 ZE40. the scale on the graphs is kW
 

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Co-author of CanZE. Q210 nov 2013
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Thank you!

For an R type motor/charger, that is completely in line with maximum draw, see Charging and cosphi third table.

For a Q model it is more complicated, because the power factor of the charger collapses pretty badly when charging @ 3 phases under 16 A.
 
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