After having Tesla reminded for several times that I really need the guide for the UMC, I still have not received a clear response. I suspect that Tesla is not willing to give me a copy as a ranger told me yesterday that the UMC does not - much to my surprise - meet the European regulations. When I told him that it was nevertheless sold to me in 2012, I got a polite smile but no (other) reaction.
Anyhow, in the meantime I have determined that I have two problems related to charging. The first - as set out earlier in this thread - is the incorrect wiring from the main panel to the UMC. The second is the 32A adapter that came with the UMC. It has a slight wobbly/not perfect connection causing resistance/heat and some coloring, probably caused by heat/warming, is visible within the adapter. Both cause voltage dropping and charging at higher Amps gives problems; the charging is cut off often, especially when ambient temps are at 25C plus. I would ask the experts among us to verify my followings plans on any danger - for the Roadster as well as for anyone or anything else.
INCORRECT WIRING: the UMC is connected to a 32A three phase system (able to deliver 230V, not 240V as I mentioned earlier). The UMC, as far as I have been able to check, does not accept/cannot be connected to all three legs of the 3 phases. The wire from the main panel to the UMC has 5 conductors, each 4mm sq. I need some 25 to 30 meters to bridge with the wiring, which runs partly through a cellar and partly under the ground. The cable is especially designed/suitable for use in the ground.
My plan is to use two pairs of conductors for the two legs of electricity (by disconnecting two of the three phase legs in the main panel) and one for the ground connection. Is there any risk in doing so? Should I take special measures in pairing the conductors? I do not mean any risks in terms of shutting off the power when the pairing will be done or connecting the correct conductors at the correct spot, but in terms of any resistance/heat that may be caused when 230V at 32A flows through paired conductors and how to limit that, if possible. Should the conductors be twisted in each other, or is it better to not do that? Or would 4mm sq. per conductor be sufficient for the 25 to 30 meters and should I not pair the conductors and leave the wiring as it is?
Another question: is there any risk in only taking the load from one leg of a three phase connection? I have done that for 2.5 years now, but without realising this.
BTW if I will proceed with this, these operations will not be done by myself but by an electrician. So do not worry.
THE 32A ADAPTER: the plan is to remove it and connect the end of the cable that is connected to the adapter - nearest to the UMC - directly in the plug (
CEE male 5 polig 6H 32A IP67 stekker 380-415VAC). The question I have here, is whether the purple wire for the pilot signal should be connected (indeed, as suggested in a couple of other threads on TMC) to the ground cable? And is there any risk or negative consequences in having the small device that is connected to the purple wire put in the plug instead of in the adapter? This device is tied to a piece of plastic that forms part of the inner side of the adapter with two tie wraps. The plug in which I plan to put it in, has nothing in it to tie it to, except for the conductors. Is it safe to tie it to the ground cable, as much as possible away for the other conductors?
Any help/reaction is appreciated.