I have a 4 wire NEMA 14-50 outlet installed when I first got my car and would use the charge cable got charge. I recently got a HPWC that I was hoping to mount on the wall and install a NEMA plug that goes to my existing outlet. Upon further I inspection I noticed the HPWC only uses the 3 wire configuration and recommends grounding the neutral. Has any one done this type of install? What did you do with your neutral lead? Ground it in the charger or convert to three wire before the HPWC?