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Discussion Starter #1
I have taken delivery today of a BMW i3 94Ah REX.

I already had a 4 year old tethered charging unit with a type 1 connector

After getting rather unhelpful advice to swap the whole unit for £450+ from chargemaster, I decided to swap just the plug on the end of the cable and this seemed to go successfully.

However the car is not charging. I feel fairly confident in the wiring except for details around the two thin control wires marked pp and cp.

Any advice or pointers to friendly companies that could help?

Thanks
 

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Discussion Starter #6
Two pictures loaded below. These show the type 1 connector before I swapped to the type 2.
20181208_140412.jpg

20181208_140355.jpg

The grey control wire was cut off short and replaced (if you can see in my pictures) with a pair of wires through a micro switch that was operated by the button on the top of the plug which also operates a physical clip. One side of this pair of wires was inserted with the earth cable and one into the PP pin.

For my Type 2 plug there is no button or micro switch so I used the grey wire in the cable (stripping back a bit further to expose enough length) and inserted PP and CP into their respective pins.

These are attached to a four year old chargemaster unit. There is a yellow light on the unit which I think is the normal power on but not charging indication.

When I plug in the cable to the i3 nothing happens.
 

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FWIW on my Rolec, the CP & PP wires simply go straight from the charger end through the cable and onto the pins on the plug. There's no electrical switching going on in my untethered cable plug at the car-end, only the mechanical clip-lock. You could try bypassing the microswitch altogether.

Also, check you have a resistor somewhere controlling the permitted-max-current for the cable.

If you google for "EPC Manual V1.2_050816_1.pdf" you'll find the Mainpine docs describing that CP & PP usage, though that doc doesn't describe the per-cable resistor.

google for "finalsaej1772" gets you the official J1772 spec. There may be a newer version than this, but the bit you're interested should be unchanged. But I can't see the inline cable-resistance values in there!

"Simple-EVSE1-1.pdf" describes the cable part. There should be a resistance measurable across PP & PE at the car-end, check when the charger is off. This should be 220 Ohms for a 32A cable, or 680 Ohms for a 16A one. On my detachable cable this resistor is fitted inside the car-plug end. On a tethered one it may be built in elsewhere, but it should be there and measurable. Hope this helps!
 

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I have taken delivery today of a BMW i3 94Ah REX.

I already had a 4 year old tethered charging unit with a type 1 connector

After getting rather unhelpful advice to swap the whole unit for £450+ from chargemaster, I decided to swap just the plug on the end of the cable and this seemed to go successfully.

However the car is not charging. I feel fairly confident in the wiring except for details around the two thin control wires marked pp and cp.

Any advice or pointers to friendly companies that could help?

Thanks
Alternatively, you could cut your losses and buy my brand new tethered cable, with a type 2 plug on the end, to rewire into the charger itself as you remove the old type 1 tethered cable. Then sell on your loose type 2 plug to someone else to fathom out. As well as the old type 1 cable.

I bought this cable very recently to do the same job that faced you by upgrading my 32amp type 1 Tethered Rolec to type 2. But then discovered that the Ioniq came with its own subsidised wall charger making the new cable redundant. It cost me £115 but I would sell it to you for £80 to solve your problem. The four wires at the charger end of the cable are easy to connect to the existing four contacts in there. Why stress. Walk away and put it down to experience. If this of interest to you ( or any other person reading this ) send me an IM.
 

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Discussion Starter #10
My plan, having read various articles and wiring diagrams and watched some youtube videos, is to connect the grey PP wire from the back of pin in the female type 2 plug end, to the earth cable.

From what I read there is a process of measuring the resistance to determine how much power the car can pull.

In some wall units (seen on youtube) the PP wire is connected to the same terminal as the earth (in the wall unit) it seems mine was set up connected to the earth in the plug itself.

This was the setup for the type 1 plug (albeit with the complication of a button and switch breaking this wire which no longer exists).

I'm going to try this tonight unless anyone here knows a reason why not?
 

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For a Type 2, the CP connects back to the controller
L1 is live (L2 and L3 are for a three phase setup)
N neutral
PE - Earth
Connect a suitable resistor between PE and PP. PP is not returned to the EVSE usually

See here Variable Rate Charger

Depends what the original cable is but if its a 16A (3.6kW) unit then do not try the 30A resistor, sorry if thats stating the obvious.

I hope you have the correct crimp tool for the large pins in the type 2 plug, these currents can be a problem with soldered joints.
 
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