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Do you carry your EVSE in the car?

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In my quest to decide on 14-50 or HPWC some people suggested getting the HPWC so that I can keep my EVSE that comes with the car in the car.

But do I really need this EVSE in the car? Wouldn't I be stopping at super chargers or other chargers if I am on the road? Just wondering how many people need to keep the EVSE in the car vs just use it at home, and how often they actually use it.

I also have a 16amp 14-30 EVSE J1772 I could put in the car instead and still save some money using the stock EVSE instead of the HPWC?
 
My EVSE has never left the trunk of any of my Tesla’s for over 4years ...lol even in the early days of not having many superchargers on long distance travel I used the J1772 adaptor more than anything ...for home I prefer the HPWC for durability and speed of charging
 
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The UMC is your portable EVSE. I prefer to keep it in the car. I've used it a couple of times at relatives houses to pick up a little 120V charge. It's also insurance against running out of charge during travel (such as a big unexpected detour) or at a destination. The downsides are cost (if duplicated in your garage) and the extra weight.
 
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in 18 months and 52,000 miles I've brought my UMC with me a grand total of three times when I wanted to trickle charge at a destination I was going to be at for an extended period (AirBNB rental, etc). Between the prevalence of Superchargers (particularly in California) and the J1772 adapter there's really almost never a need to bring your own cable.
 
I've driven my MS85 40K+ miles in a little over 2 years. I regularly travel 100+ miles for work daily. I only bring my UMC with me on a planned trip of more than 200 miles or so. I've never needed it otherwise. I use the UMC at home as my primary charger.

As folks have said, the supercharger network has grown and is usually where it needs to be for most travel. I have always managed to find a J1772 charger as well if I wasn't close enough to a supercharger at my destination. I'm on the east coast, it's even more prevalent on the west coast.

I never found it was worth the extra money to purchase a spare, just to have one in the car. I just always remember it as the last item on a checklist before a trip if I need to bring it. Both kids, check, wife, check, toothbrush, check, UMC, check.
 
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Suppose your in real need of a charge and the supercharger you select is down......what to do.....look for an RV park or Ji772 down the road........oops, forgot my UMC........now what?

Use the J1772 adapter that I keep in the car at any of eleventy billion public L2 charging stations, which are far more prevalent at this point than RV parks or random outlets.
 
I was at my cabin with a HPWC (first Gen) that the 3 decided it didn't want to work with it -- after many attempts. My S was there too so I dug out my UMC and extension cord that I always keep in the S, and plugged it into the stove plug. No go too -- I got the same error message. Worried, I opened up the new UMC (for its first use) and it worked -- huge sigh of relief! If I didn't have the UMC in the car, and an extension cord to reach (from my S), I would have needed a tow or the UMC from home -- but I really didn't think it was going to work so I doubt I would have got it. I emailed Tesla about it and they do know about it -- there's also threads here about it. This weekend, without my 3 taking an update, the HPWC works fine with it. I haven't tried my S's UMC since. I have a first gen HPWC at home and it's always worked (knocked wood).

In any event, I'm really glad I had it with me but I bet I won't use it much.
 
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I agree with others that for most people's use cases don't require them to carry around a UMC, but I am a bit of a disaster planning boy scout. I hate to be caught unprepared. The UMC Gen 2 is pretty small, so keeping it tucked in the trunk or frunk is not a big deal.

In the event of a major emergency I want the ability to charge at any "plug of opportunity".

I guess it all depends on your use cases...
 
But do I really need this EVSE in the car?
I keep the UMC and full suite of outlet adapters in the frunk. Not really necessary for local driving. Just don’t have to remember to pack it when going more than 100 miles away from home. Also, there are rare scenarios where it could be useful or vital.

I do add 50-foot 6-50 welder extension cord with dryer plug adapters for road trips.

I’m a tech over-prepare type. Keep a flat international plug adapter in my laptop backpack though I travel out of the country only once a year. And a flat adapter that provides 3 outlets from a single 120 Volt wall socket.
 
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Only when I travel. My sister & brother live out in the country, so there are minimal public charging options (she's outside of Orange Grove, TX while he's outside of Nekoosa, WI). Both have installed 14-30 outlets for when I visit.

Reason for 14-30 instead of 14-50 is the parking area at my sister's is on the back side of their property, far enough from the breaker box that their electrician said to go with a 30A circuit. At my brother's the outlet is at the back of their [used for storage] garage, so when I visit him I also bring the 14-30 extension cord I'd already purchased for use at home (I work from home so the 5-15 in the garage is normally adequate, but I have an unused 14-30 inside the house for the rare occasions I need a faster charge).
 
There is no reason to keep it in the car. There is no conceivable emergency in which you would need it in your daily driving. Keep it plugged into the outlet in your garage, hanging on a hook, and take it with you on out of town trips. Even then you’re not likely to use it but good to have for emergencies.
 
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