When I charge my car, I usually try to lay out my charging cable so that there are no loops in the cable. That is, no part of the cable touches another part of the cable. I believe the current going into the car is AC, so I imagine there is some (hopefully small) amount of inductance created by any loops in the cable. Does this matter in terms of either charging efficiency or safety?
Wow! I never considered this and someone will hopefully do the math here (it’s been too long!), but I really doubt there is any measurable effect. The electromagnetic field exists with or without loops. There is or would be shielding in the wire if that would be of any concerns. Besides, might be a bit too optimistic, but I think we would have heard of any issues by now (not just from charging an EV). Envoyé de mon iPhone en utilisant Inside EVs
Unless you're driving a Clarity EV, the car is not capable of accepting a DC charge so don't worry about that. Actually, don't worry about the whole issue - it's not a problem. If it were, every power cord on every device and appliance in your home would need to be laid-out straight. Chillax!
I felt like I had better luck with the Chargepoint chargers when I laid out the cable. Seemed like the coils were interfering with the communication square wave.
Assuming you have a 240v@32a EVSE, that's still less power than some induction stovetops require, and I'm pretty sure those induction stovetops don't have a half inch of insulation in the coils. I wouldn't hang my steel pan in front of the coiled charging cable, but only because that'd make it really hard to get to the cable and the edges of the pan would slice through it if I pulled on it
Short Answer: No, it does not matter in terms of charging efficiency or safety. Coil away! Long Answer (shortened for simplicity): All current carrying conductors create a magnetic field (EMF). However, since both L1 and L2 conductors are next to each other in the cable, and their currents flow in opposite directions, the EMF of one conductor "effectively"* cancels out the the EMF of the second conductor. [*Not "absolutely" because they are not perfectly collinear, but certainly "effectively" and beyond normal measurement capabilities.] If you wanted to make a transformer, you would have to cut the outer cable sheath, split apart the L1 and L2 conductors, and coil them separately. You would then have an air core transformer (although a poor one). Wrap the now split apart conductors around and iron core and you have a "real" transformer. Short of doing the above ridiculous shenanigan, you won't be able to detect or measure the "loss of power" of a coiled up intact normal power cable. This is why when running industrial power cables (typically 3-phase), all three phases are run together in the same conduit, with the conduit grounded. Even if there are multiple cables per phase requiring multiple conduits (say 3 cables per each of phases A, B and C), then you run one cable of each phase in conduit 1, one cable of each phase in conduit 2 and one cable of each phase in conduit 3 (this is one example, there are of course variations).
OK, here's another somewhat related question: If my car and charging cable are outside in the sun, do I need to be concerned about exposing the cable to sun and charging at the same time? That is, do I need to be concerned about high temperatures?
No. What you need to be worried about in that case is the cable getting brittle when the plastic/rubber is exposed to UV. Given the box isn't waterproof, I don't think Honda would've spent the extra money on a UV-resistant cable.
