R22 State B to State C transition time

[david.b]

We have a vehicle with an onboard charger (Bel Power 350INVCH150-120-240-8G) that claims compliance to J1772 and not IEC 61851.

After connecting the vehicle to a evnex R22 (AI20490995XXY), the CP line drops to 8.7V as expected and after 4.5 seconds, the R22 applies a 1kHz 50% wave but displays an error after 200mS.

{
  "errorCode": "OtherError",
  "vendorErrorCode": "Pilot Fault",
  "connectorId": 1,
  "status": "Faulted"
}

Looking at previous logs from other EVSE, it appears the charger dwells in state B for ~10 seconds before applying the S2 to transition to state C.

It appears the R22 only waits 200mS before erroring. Is this per IEC 61851 or is this time able to be changed?

[Ashley]

Hi David,

We have reviewed your error message and scope picture. Thanks for sending such detailed information. The fault you are seeing is caused by the pilot signal not being within defined high and low voltage ranges while in the B2 state.

The required voltage ranges are -13.0 to -11.0 Volts for the low part of the PWM signal and 7.5 to 10.5 Volts for the high part of the signal.

In your scope picture it looks like it may not quite be reaching -11 Volts at the bottom right of the PWM area.

If you could please send a close up scope picture of the PWM signal near the end of the PWM just before it faults we could confirm this.

Regards

Ashley
Evnex

[david.b]

Thanks for your response Ashley, attached is an image showing the bottom of the waveform. It appears ok.

[david.b]

One more picture - each pulse seems to have a slow slope to the minimum voltage as indicated below:

[Ashley]

Hi David,

Thanks for the updated pictures. The pilot signal will be measuring around -10.5V which is the cause of your fault. There seems to be a lot of curve on that signal. Possibly the on board charger or the cable has excessive capacitance. J1772 defines a limit for the capacitance on the cable and the on board charger.

The PWM signal would normally be very square. Also, the negative side of the PWM is very close to the -11V limit even when it is stable. It would be OK, but normally you would see -11.8 to -12.0V.

What type of vehicle are you charging?

Regards

Ashley
Evnex

[david.b]

Thanks Ashley, the vehicle is a converted Toyota LandCruiser as as mentioned in my initial email uses a Bel power onboard 22kw charger.

We have successfully charge the vehicle using a evbox businessline EVSE which is also certified to IEC 61851:2017.

We will check the cabling and try and different lead and get back to you.

[david.b]

Hi Ashley, we identified a 46k of resistance across the CP line that was used for a PLC input on the vehicle. We have removed this resistance and the R22 is successfully charging. Thanks for your help.

[Ashley]

Good find! Glad you got it all sorted. Thanks for letting us know.

[david.b]

Hi Ashley,

I intended to include the below - showing bottom of the pulse after removing the additional resistance:

Dave