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Do you drive with a UMC in the Trunk/Frunk?

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Al Sherman

It's about THIS car.
Nov 29, 2012
1,687
6
Batesville, IN
I've read that folks don't think it's good for the plug to keep plugging and unplugging. I'm guessing I'll just be too lazy. I'll obviously have it with me with all the adaptors for road trips.

Do I need it in the car for just daily driving with no range anxiety whatsoever? Are you doing this? Did you/Will you buy an extra UMC for this purpose?
 
I heard an idea to minimize the stress on the outlet and the plug was to leave the "adapter" portion of the UMC in the outlet. And disconnect only from the point from the adapter-connector. The thought is that connection point is less prone to wear/damage than the 14-50 outlet would be.
 
I leave the UMC plugged into the wall socket. The J1772 adapter would be much more likely to be useful in any local charging. I do intend to get a second UMC before I take any trips.
 
I've read that folks don't think it's good for the plug to keep plugging and unplugging. I'm guessing I'll just be too lazy. I'll obviously have it with me with all the adaptors for road trips.

Do I need it in the car for just daily driving with no range anxiety whatsoever? Are you doing this? Did you/Will you buy an extra UMC for this purpose?

If you have no range anxiety, like me, then why bother? I have a 46-mile round trip to work, so even with a bunch of side errands or going to the movies or shopping or whatever, I won't need to charge away from home. I never make unplanned road trips to other cities. ;-) You know what stuff you do around town, your commute, etc.--only you can judge what's best for you. But for my driving situation, I wouldn't unplug it just to have it with me.

Reading this thread makes me realize, though, since I have the bag o' adapters in the trunk (including the J1772 adapter), I can charge from a public charging station anyway. This wasn't exactly a conscious plan, though. Whether or not this seems sufficient for you depends on your charging infrastructure and your driving situation.

I haven't looked closely, but I'm skeptical unplugging the adapter regularly is a big deal. But I only need to unplug if I go on a road trip, and theoretically my HPWC will arrive some day, and then I'll keep the UMC in the trunk with all adapters since I won't need it at home any longer. But even without an HPWC I wouldn't buy an extra UMC (again, my situation--no range anxiety, no need to charge, plus I have the J1772 in the trunk) since I don't believe that unplugging from the wall a few times a year is going to make the adapter fail. That's just silly IMHO; they can't be that fragile.

/ramble ;-)
 
2 comments.

1st: the trunk def gets more usage than the frunk. This is simply b/c closing the frunk kind of scares me. I feel like with frequent usage the hood may get bent. For such a forward thinking company that is trying to break the traditional car paradigm, I wish Tesla would have designed the frunk to open/close like a trunk. (Rather than opening/closing like a traditional hood). It doesn't even have to be an automatic/electric/power mechanism (like the option offered on the trunk)....just manual would have been fine. I can open it with the touchscreen or the key fob and if I could just drop the hood (or slam it) shut like a normal trunk I would actually prefer the frunk to the trunk (since it is a hidden compartment whereas trunk is openly visible (unless you use the hidden footwell compartment in the trunk).

2nd: wouldn't leaving in the plug (in the wall) mean electricity is flowing to the UMC? (Hence the green light is on). Wouldn't this eventually wear out the UMC? (Burn it out or overheat it?). And unplugging and replugging the unit shouldn't cause any problems if you had a good installation. (My wall socket doesn't wiggle or jiggle). I always unplug mine and always bring it along (in the trunk) just in case. It did actually pay off once when there was a death in the family and I had to leave work early and go to the funeral. If I would have left my charger at home I would still probably just made it (but would have had the dreaded EVers "range anxiety"). Since I had it with me, I charged up and avoided that anxiety (which was good b/c there was more important things going on....).
 
Before the HPWC arrived, I left the UMC plugged in in the garage nearly always. I took it once or twice when I thought I might need to use it. Now that the HPWC has been installed, I have the UMC bundled up and stored in the trunk. I leave it there, so it will always be there if I should require it.
 
2nd: wouldn't leaving in the plug (in the wall) mean electricity is flowing to the UMC? (Hence the green light is on). Wouldn't this eventually wear out the UMC? (Burn it out or overheat it?). And unplugging and replugging the unit shouldn't cause any problems if you had a good installation. (My wall socket doesn't wiggle or jiggle). I always unplug mine and always bring it along (in the trunk) just in case.

The UMC is not going to "wear out". Be warned that the NEMA 14-50 plug is not designed for repeated plug/unplug cycles. If you unplug frequently you would be advised to replace the socket every couple of years. Fortunately they are cheap.
 
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I get free 110 volt juice at work as well as a prime parking spot dedicated to EVs so I really need a cable with me in the vehicle. Is there any chance that somebody on the forum is going to offer an inexpensive lighter weight dedicated 110 volt charge cord? It doesn't sound like Tesla plans on offering anything other than the full UMC. I really don't need the full power and flexibility of the UMC for my use at the office (and I'd really like to keep my UMC plugged into my garage.)

I know the Roadster had a separate 110 volt cable so I was really hoping one would be available for the Model S as well. If I have to buy another UMC in order to get the preferred parking and free power at work then I will but I'm hoping for a cheaper solution. Any thoughts?
 
I get free 110 volt juice at work as well as a prime parking spot dedicated to EVs so I really need a cable with me in the vehicle. Is there any chance that somebody on the forum is going to offer an inexpensive lighter weight dedicated 110 volt charge cord? It doesn't sound like Tesla plans on offering anything other than the full UMC. I really don't need the full power and flexibility of the UMC for my use at the office (and I'd really like to keep my UMC plugged into my garage.)

I know the Roadster had a separate 110 volt cable so I was really hoping one would be available for the Model S as well. If I have to buy another UMC in order to get the preferred parking and free power at work then I will but I'm hoping for a cheaper solution. Any thoughts?

Considering that most EVSEs are somewhere in the neighborhood of $700-800 and going much higher, I think you'll be hard pressed to do much cheaper than a spare UMC at $500.
 
Considering that most EVSEs are somewhere in the neighborhood of $700-800 and going much higher, I think you'll be hard pressed to do much cheaper than a spare UMC at $500.

Yes, that's as low as they go. In the current market, the Tesla UMC is a bargain.

Of course, given the relative simplicity of the electronics in them, they're all over-priced. I would expect to see the prices come way down over time as the EV numbers grow.
 
I am considering a second UMC, not because I think I will need it to charge away from home that often, but if I ever do need to, and the cable is damaged (or vandalized), then I'm hosed, so to speak. It could take a couple of weeks or more for a replacement UMC to arrive from Tesla and I wouldn't have the ability to charge up at home during that wait. Most inconvenient.
 
Same as Supercoug; I have free charging at work but, I don't usually get (or need) the J1772 spots - I park in one of many EV-only spots with 110V outlets instead.

Why give up on free juice, the nice dedicated spots and the chance to EVangelize by just parking there?!

So, I unplug the UMC from my home 14-50 outlet daily *while leaving the actual 14-50 plug behind in the outlet*. I expect the wear to be less that way. Tesla's UMC design is very nice with the ability to decouple the cable from the actual plug.

OTOH, my 110V plug is seeing a lot of plug/unplug cycles at work and that too with the outlet oriented the *wrong* way with a kink in the cable (with the weight of the whatchamacallit box bending the cable) so, both the 110V plug and the UMC cable are getting some workout every day.

I have a due bill item of the missing aluminum trim on the UMC end and folks have experienced that Tesla is replacing the entire UMC for that. If that's the case - I'll have to stop by Menlo Park one of these days - and if I can convince the guys there to let me keep the now-used trim-less UMC for a price less than $500, I'll make that deal.