Portable charging with a wall mounted box?

this may be a really dumb question but I'm going to ask it anyway....

Is there any reason why I cannot use a wall mountable charging box as a portable charging unit? What I was thinking of was something like the attached. Instead of connecting the box to the wall, I would just put it in the frunk for the very odd occasions when I need it. The power end would be terminated in a 32A commando (RV) plug instead of being connected directly into a domestic fuse box. I already have a set of 32A ->16A camp ground, 32A ->16A European Schuko and 32A - >UK 13A domestic plugs (all single phase) and obviously I can set the maximum current to be drawn in the car itself. When arriving at a destination to charge, I can just suspend the charging unit from somewhere suitable, connect the plug (via an adapter if need be ) to the 32A/16A/13A socket, and then charge the car.

Why do this? Well the British government has been subsidising the fitting of these wall mounted devices and increasing numbers are now coming onto the market second hand. I can pick one up for about a third of the price of a UMC and about 20% or less of the price of a Juice Booster. I know it would be much bigger than a UMC but for the amount of times it will be used I actually don't care.

Any thoughts would be really welcome: I pick up my MS tomorrow night so I really need to decide by then whether to drop £500/$850 on a UMC or not as I am too far from the service centre to want to go back to pick one up later.

Thanks

Thanks gavine....the point is that I don't yet have ANY portable EVSE (I have a Polar home charger but that is all). So (a) I wouldn't need this for home and (b) I don't have a UMC (yet) to cart around...

arg, thanks for your thoughts. To be honest the whole issue of portable charging is driving me nuts. I am an electronics engineer and my brother in law is an electrician. We did look into the build your own but the cost is actually quite significant (a type 2 plug plus cable is about £100, so is the Mainpine unit, a decent breaker and RCBO will be a few tens of quid, a waterproof/splashproof DIN box will be another few tens of quid, plus then there is the current switch (I agree that relying upon maximum current by setting the software in the car is asking for trouble with my wife too, so I would want to build a rotary or press button maximum current switch)...plus then there all of the pigtails to build (to 32A blue commando/16A blue commando/13A BS1363 with built in thermal cutoff)...I totted up that it was going to be £300 or so plus an evening's work for something that will look like a breezeblock when finished.

The UMC is £500 or so and I can buy the 32A single phase version and build my own adapters I think. But you are right that then leaves me with the risk of tripping things if I or Mrs F forgets to set the car current properly. I suppose I could build adapters with current limiters in them (so, say, blue 32A commando to 16A commando with a few feet of cable and a current limiter inline to prevent more than 16A being drawn; plus 32a to 13A with a current limiter and thermal sensor/cutout) but again this is all a bit of a faff.

The Juice Booster is a nice piece of kit but I just don't have a grand to spend on it (the money is earmarked for a custom subwoofer and upgraded speakers ) and anyway - which is where my point was headed - I really do wonder how much I will ever use a portable EVSE. 99% of my driving is to work and back or to see family, all bar one of which lives within 35 miles of our house. it's only one of my friends in Oxford and some family in Dorset where I will really need to think about "domestic" charging.

Although I have been more aware of the issue over the last few months as I have waited for my MS, I have to confess that I don't see a lot of 32A commando sockets knocking around and I wonder for the sake of 3-6 times per year whether I should just forget about it and go for a 13A EVSE (there are several on the market, for about £300-£400 as you note, all with thermal cutouts built in).

But then my issue is that there is a big (actually road trip deal breaking) difference between charging at 10-13A (let's say 10A for most domestic circuits) and the 16A that I know I can get quite regularly (my family in Dorset live 400m from a campsite with tons of 16A sockets, and my mate in Oxford is a sparky who has offered to stick a 16A commando socket in his garage for me). With 16A I can travel to Dorset (200 miles) on a range charge and be fully range charged to go home by the end of the weekend (I reckon it is about 20 hours of charging). With a 13A socket, it's just not going to work.

Any thoughts/help most welcome....I have realised that there is no right answer, but I have recognised that I do need something, none of those "somethings" are cheap, and I don't want to regret what I end up buying!

Oh, and, yes sorry the photo was simply a "serving suggestion", I did not look that closely at the plug on the end which is indeed a type 1 as you say. I had not however thought about the modem issue. The Polar unit that I had installed a few weeks ago does NOT seem to have one....well if it does then they are getting a magic mobile signal since I cannot get a signal at home on any of the networks!

Thanks