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Discussion Starter #1 (Edited)
Hi all - Does anyone have a Rolec (Type 2) charging point in the Ackworth/Wakefield/Barnsley area I could test my BMW 530E with?

I purchased one its the 7.2KWh 32A version - although the car is just 3.6KWh charging (We have a Jaguar that uses it also at a higher charge rate), tried other type 2 cables as well , no difference.

When I plug the 530E in it stops charging after 30 secs to a min and the car shows a charging error (Have tried all three charging rate options - No difference)

The BMW 530E works on the granny charger and also at POD points I have tried (Tesco).

Our company Jag (EV) and also a BMW 330E (Son in law's) charges fine on the Rolec we installed but the 530E fails every time. (I have tried it with minimal and half charge on the car battery at a suggestion - just the same)

My Car also would not Charge on another Rolec at our southern office, but I just want to try at least one other to prove this. BMW garage Chargers work fine too.

The earth on the Rolec is a TT earth spike at 32 Ohms (Changed from standard after Rolec suggested the earth may be the problem).
Also Rolec had it back and said the communications module was faulty and replaced it - (No difference)

Can anyone confirm what negotiates the charging current with the car - is it resistance on two of the pins or a 1KHz signal with different timescale for each methodology (I have seen differing opinions online), I'm thinking of getting an storage oscilloscope on the CP wire to see what we get now!

BMW have offered to check the vehicle again - but I think they just plug it into their charger and if it works thats fine...

I would like to gain some evidence to either point to BMW or Rolec so I can get it sorted out (unit is in Barnsley - anyone local is welcome to test it).

Any help will be recieved gratefully

Robert
 

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Hi Robert I've a rolec 7.3kw 32amp charger at home ( Wakefield) your welcome to bob over and try it if you can't find anyone who can help nearer
Ashley
 

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Can anyone confirm what negotiates the charging current with the car - is it resistance on two of the pins or a 1KHz signal with different timescale for each methodology (I have seen differing opinions online), I'm thinking of getting an storage oscilloscope on the CP wire to see what we get now!
The charging point signals to the car (using the mark/space ratio of the 1kHz signal) the maximum current that the car may draw. The charging cable by the resistance between two pins signals to the charging point the maximum current rating of the cable, which then adjusts the mark/space ratio of the 1kHz signal to the car if the charging cable has a lower current carrying capacity than what the charging point would otherwise supply.

Some charging points are also capable of signalling the car to reduce the maximum current drawn when the supply to the house would otherwise be overloaded - this requires a current transformer clamp on one of the house's incoming supply wires and a means of communicating this information to the charging point. Very useful if otherwise charging the car and running the electric shower would overload the house supply cable.
 

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The EVSEs will also monitor the voltage supplied by the grid, and if that drops too low, it's a failure situation & charging will stop. If you can, try setting your to car to charge at a low current, e.g. if it works at 3.3 kW but not at 7, then this might be the cause. Could be low volts from the grid to begin with, or the length of cable from CU to EVSE may be dropping he voltage too much under max current load, suggesting you need a thicker cable from the CU. You'll need to stick a voltmeter on the mains input to the EVSE when charging starts to check this.
 

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Discussion Starter #7
Hi Robert I've a rolec 7.3kw 32amp charger at home ( Wakefield) your welcome to bob over and try it if you can't find anyone who can help nearer
Ashley
Hi Robert I've a rolec 7.3kw 32amp charger at home ( Wakefield) your welcome to bob over and try it if you can't find anyone who can help nearer
Ashley
Hi Again, Hi yes please let me know when its convenient, should only take ten mins.

Thanks

Robert
 

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The EVSEs will also monitor the voltage supplied by the grid, and if that drops too low, it's a failure situation & charging will stop. If you can, try setting your to car to charge at a low current, e.g. if it works at 3.3 kW but not at 7, then this might be the cause. Could be low volts from the grid to begin with, or the length of cable from CU to EVSE may be dropping he voltage too much under max current load, suggesting you need a thicker cable from the CU. You'll need to stick a voltmeter on the mains input to the EVSE when charging starts to check this.
Hi, Thanks, I have tried all three charging modes on the car, Voltage and earth is fine according to electrician, tried different type 2 cables. Also the unit works fine on a 330e and jag in 'any' and all charging modes?
 

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Does sound like a car fault to me, as all the other Evs seem to work fine. If you want to try to diagnose it a bit further yourself with a scope, you're going to need one that captures & stores a lot of waveform, as you'll want to monitor the voltage level on the CP line at the point the charging stops. CP starts out at +12V; plugging the car in reduces that to 9V, and when the car wants power it drops it a bit more to 6V (switches in anotehr resistor aross that and ground), and somewhere around this point the EVSE starts PWMming the CP line to supply the max current info the car needs, and closes teh contactor to energise the mains wire. If the car decides it's had enough of a charge, it will let the CP line float back up to 9V, and the EVSE detects this & stops the charge & opens the contactors. But if the EVSE decides to stop the charge, it will stop the PWMming, and at some point open the contactors. I'm not sure if it will wait for thr car to let the CP line float up to 9V after stopping PWMming, but I suspect not, as e.g. suppose someone cut all power to the EVSE, then the contactors would have to open immediately, regardless of what the car was doing. In this scenario, my Ampy detects that something's gone wrong with the EVSE & flags up a moaning message to tell me, but yours might not.
 

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this sounds like a user error. Are you plugging it in correctly?

Hi all - Does anyone have a Rolec (Type 2) charging point in the Ackworth/Wakefield/Barnsley area I could test my BMW 530E with?

I purchased one its the 7.2KWh 32A version - although the car is just 3.6KWh charging (We have a Jaguar that uses it also at a higher charge rate), tried other type 2 cables as well , no difference.

When I plug the 530E in it stops charging after 30 secs to a min and the car shows a charging error (Have tried all three charging rate options - No difference)

The BMW 530E works on the granny charger and also at POD points I have tried (Tesco).

Our company Jag (EV) and also a BMW 330E (Son in law's) charges fine on the Rolec we installed but the 530E fails every time. (I have tried it with minimal and half charge on the car battery at a suggestion - just the same)

My Car also would not Charge on another Rolec at our southern office, but I just want to try at least one other to prove this. BMW garage Chargers work fine too.

The earth on the Rolec is a TT earth spike at 32 Ohms (Changed from standard after Rolec suggested the earth may be the problem).
Also Rolec had it back and said the communications module was faulty and replaced it - (No difference)

Can anyone confirm what negotiates the charging current with the car - is it resistance on two of the pins or a 1KHz signal with different timescale for each methodology (I have seen differing opinions online), I'm thinking of getting an storage oscilloscope on the CP wire to see what we get now!

BMW have offered to check the vehicle again - but I think they just plug it into their charger and if it works thats fine...

I would like to gain some evidence to either point to BMW or Rolec so I can get it sorted out (unit is in Barnsley - anyone local is welcome to test it).

Any help will be recieved gratefully

Robert
 
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