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Hack UMC to get 48 amps?

SabrToothSqrl

Active Member
Dec 5, 2014
3,741
3,042
PA
So, with the now in production X accepting up to 48 amps standard, and 72 optional...

Can one, theoretically modify a UMC to tell the car it's allowed to pull 48 amps?

So, if you had a NEMA 14-60, rated for 60 amps, and 48 amps is the continuous 80% load of that, and managed to wire it all, and ignoring all safety concerns/etc.

Especially since it's only 8 more amps ;)
COULD this be done?

Why not offer a NEMA 14-60 adapter for the UMC? If you were installed a new outlet in your location, why not select the 60? (assuming appropriate wiring behind it).

Yes I know they don't sell one, yes I know electricity is dangerous, that's why I always check for power by licking the black wire.

So... who's gonna try it first :)?
 

Vger

Active Member
Apr 10, 2009
1,781
210
Salt Spring Island, BC, Canada
It is technically possible, but the whole UMC would need to be re-engineered. The wire gauge, adapter disconnect design, and probably other components are rated from only 40A continuous. I have, and others have had problems with UMC's melting under a full 10kW load in hot ambient temperatures (especially in direct sun at an RV park).

I think this needs better than a hack, if you want to keep your car, garage, house, neighbourhood. :wink:
 
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green1

Active Member
Mar 25, 2014
4,548
1,121
Calgary, Alberta, Canada
Isn't the UMC basically just a relay? What components in it would be an issue?
Everything. Some people report the UMC getting warm at 40A, pushing it 20% above it's design current rating is asking for a fire.

The UMC that comes with the X is the same as the S?
Hard to be 100% positive, but I can't see any reason it wouldn't be.

If going to all this effort, and considering how incredibly rare 14-60 outlets are in the wild, you're probably better off to just get an HPWC instead of installing one.
 

green1

Active Member
Mar 25, 2014
4,548
1,121
Calgary, Alberta, Canada
UMC Tip = $40 Outlet = $7.00

HPWC = $750.
A new house is several hundred thousand dollars when you burn your existing one down after modifying your UMC intentionally which voided your fire insurance...

Just saying that the whole thing isn't designed for it, Heck, in Canada they now refuse to rate the UMC at even 40A and we can't get adapters to do more than 32A anymore, you want to up it to 48A you're going to need a whole new everything, thicker wire, beefier electronics, bigger fuses, everything. Completely rebuilding the UMC to handle the required amount of current safely is pretty much guaranteed to require more than $750 worth of work.
 

SabrToothSqrl

Active Member
Dec 5, 2014
3,741
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PA
I get your point... Here in the US though, stupidity is covered by insurance. Even if your "DO NOT USE INSIDE" heater burns your house down...

but yea, I guess there's a lot more to it than changing the tip.

So, what's the logic behind the 48 amps thing?! I'm not spending $750 for 8 amps...
 

ptsagcy

Member
Nov 4, 2013
528
176
NJ
I get your point... Here in the US though, stupidity is covered by insurance. Even if your "DO NOT USE INSIDE" heater burns your house down...

but yea, I guess there's a lot more to it than changing the tip.

So, what's the logic behind the 48 amps thing?! I'm not spending $750 for 8 amps...

The real benefit of the HPWC, besides the convenience of not having to plug and unplug the UMC every time, is if you have the 72A charger, you can charge at 72A.
 

Chris TX

Active Member
Sep 30, 2013
1,531
186
Dallas, TX
I get your point... Here in the US though, stupidity is covered by insurance. Even if your "DO NOT USE INSIDE" heater burns your house down...

but yea, I guess there's a lot more to it than changing the tip.

So, what's the logic behind the 48 amps thing?! I'm not spending $750 for 8 amps...

Plenty of people buy HPWC to charge their Model S at 40A. It's a way to keep the UMC in the car, it's a bit more robust, it's UL listed, it's going to be 1% or more efficient because of the much thicker wire gauge on the output side. 8 more amps miiiight work through the UMC if you're charging outside while it's cold. Why risk it for 8 more amps? You'd still need to hack the pilot signal to trick the car into accepting 48A, too. I still say a 60A OpenEVSE is the best thing for 48A.
 

Canuck

Well-Known Member
Nov 30, 2013
6,125
5,470
South Surrey, BC
A new house is several hundred thousand dollars when you burn your existing one down after modifying your UMC intentionally which voided your fire insurance...

Green1 - what exclusion or limitation clause are you citing in your policy when you say this? Do you actually have an anticoncurrent causation clause in a homeowner insurance policy issued in Canada? If so, that's news to me and you really need to consider switching insurers. I also wonder who would buy a policy of insurance that doesn't cover you for breaching code requirements (since code breaches are a common cause of loss) but in the States there are such policies, although the Courts won't always enforce them depending on what State you live in.

I've posted information about this issue before here:

FAQ: Home Tesla charging infrastructure QA - Page 15
 

green1

Active Member
Mar 25, 2014
4,548
1,121
Calgary, Alberta, Canada
Green1 - what exclusion or limitation clause are you citing in your policy when you say this? Do you actually have an anticoncurrent causation clause in a homeowner insurance policy issued in Canada? If so, that's news to me and you really need to consider switching insurers. I also wonder who would buy a policy of insurance that doesn't cover you for breaching code requirements (since code breaches are a common cause of loss) but in the States there are such policies, although the Courts won't always enforce them depending on what State you live in.

I've posted information about this issue before here:

FAQ: Home Tesla charging infrastructure QA - Page 15
There is a clause that they don't cover negligence "the loss did not occur through any wilful act or neglect, or the procurement, means or connivance of the Insured" I'm pretty sure modifying an electrical appliance to draw 20% more current than rated for (or in Canada 50% more than rated for) could easily be considered negligent
 

Canuck

Well-Known Member
Nov 30, 2013
6,125
5,470
South Surrey, BC
There is a clause that they don't cover negligence "the loss did not occur through any wilful act or neglect, or the procurement, means or connivance of the Insured" I'm pretty sure modifying an electrical appliance to draw 20% more current than rated for (or in Canada 50% more than rated for) could easily be considered negligent

Negligence is covered. That's one of the main purposes of insurance. The clause you quoted deals with intentional acts. The "neglect" does not mean negligence. It means if you have knowledge of an intentional act and neglect to do anything about it (i.e. your spouse is going to burn down your house and you don't alert authorities) then you do not have coverage. Or if you procure or connive in the intentional act (i.e. you have someone else burn your house down - procure, or you secretly allow - connive). The ejusdem generis rule applies to that clause and the word "neglect". There's a ton of case-law on it.

In fact, the clause you quoted comes directly from the Insurance Act. For example, that exact wording is contained in section 29, Statutory Condition 6(1)(iii) of BC's Insurance Act here (Alberta is similar but the section will be different):

(iii) stating that the loss did not occur through any wilful act or neglect or the procurement, means or connivance of the insured,

Table of Contents - Insurance Act

It is also contained on the Insurance Bureau of Canada Proof of Loss form (about 3/4 down the page).

"The said loss or damage did not occur through any willful act, neglect, procurement, means or connivance of the Insured or this declarant."

Fire:
http://assets.ibc.ca/Documents/Legal/Claims_Forms/GST/17CLAIMFRM.7.GST_2013.pdf

Other than Fire:
http://assets.ibc.ca/Documents/Legal/Claims_Forms/GST/19CLAIMFRM.8.GST_2013.pdf

If we accept that negligence is not covered, if you forget to close the door on your fireplace and it causes a fire - there's no coverage because you're negligent. That's absurd and defeats the entire purpose of insurance. Now, if you adapt your UMC with the intent of burning your house down, and you want to make it look like an accident, then there is no coverage. That's very different than messing with something and accidentally causing a fire. That's very common and insurance pays those claims daily.

Having said the foregoing, I agree it's best not to mess with your UMC and insurance companies often deny claims without proper cause. But I don't want people to be left with the impression that there is no coverage in the absence of an anticoncurrent causation clause and even if there is one, you may live in a State where the Courts will not enforce it. As I said before, if you didn't intentionally burn your house down, and your claim is denied, seek legal advice. And if you have an insurance policy with an anticoncurrent causation clause then change insurers!
 
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