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183V @ 32A - 22 mi/h

cantsingh

Member
Oct 7, 2019
26
4
DMV
Hey guys. My apartment building installed a 14-50 and I plugged my mobile connector into it with the provided 14-50 adapter. I'm showing a charge rate of ~22 mi / hour (32A @ 183V). This seems low to me... is there anything I should be concerned about? Should I lower the amperage manually in the Model 3?
 

jmaddr

Member
Mar 29, 2019
957
962
Florida
183 volts? Do you know if they installed a 208 or 240 service. Even if 208 volts that’s a heck of a drop. I’d have the electrician check the voltage. That’s likely your issue.

Changing the amperage wont change anything unless it’s too low.
 

cantsingh

Member
Oct 7, 2019
26
4
DMV
I'm not really worried about the charging rate, it's fast enough for my needs - I just mean, as you suggested, it's likely a 208V or 240V line and the fluctuations I've seen make me concerned about the health of the circuit (and my vehicle) more than anything else.

BTW, since I created this thread I looked at my app for charging rate a few more times and saw it once at 24A @ 190V and another time back at 32A @ 181V, 182V and 183V.
 

cantsingh

Member
Oct 7, 2019
26
4
DMV
Sorry, not sure what they installed. This is a large, new apartment building and they seem to have just installed a 14-50 at an existing junction box. I'd imagine this is on 208V circuit but am not sure.
 

Big Earl

bnkwupt
Jul 12, 2017
5,558
10,339
Springfield, VA
What is the voltage with no load - before the car ramps up its charging? 183 volts is very low, even for a 208 volt circuit. It won't hurt the car, but your home appliances and electronics might not like it if you have low voltage on your regular 120 volt outlets, as well.
 
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cantsingh

Member
Oct 7, 2019
26
4
DMV
That's a good question. Assuming there's no potential for damage to the car (or the socket / the apartment building?) then I won't worry about it and just double check next time I go to charge up. I haven't seen any indications the actual outlets in the unit have any issues, but we're also about 10 floors away.
 

ZOMGVTEK

Member
May 19, 2015
559
434
'Merica
The better metric to use is how much the voltage drops under load, but that's not really that great as well. If the line is really long, you're going to get huge voltage drops under load. And the starting voltage is going to vary based on your location, time of day, weather, other loads, and whatnot. The grid more or less doesn't control voltage, so if you have 208V service its totally possible you can see 190v service into the building unloaded. The incoming voltage is more likely to be low in an industrial area during peak hours, or hot weather. Add a long run and under load 180's are totally sensible. Really the surefire way to check for an issue, is load the circuit and check all connections with a thermal camera. That's usually not very practical for most people though.
 
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CharleyBC

Active Member
Jun 28, 2019
1,403
1,590
Talent, OR
Given that voltage, your 22 mi/hour charge rate sounds about right. But, yeah, what's the deal with that voltage? You show your location as "dmv". I'm not sure where that is. Is that a typical voltage there? We typically get about 244V here in Sacramento, which gives us about 31 mi/hour of charge.
 

Rocky_H

Well-Known Member
Feb 19, 2015
6,441
7,667
Boise, ID
This doesn't seem too surprising. You mention it's an apartment, so almost certainly it's the nominal "208V". But big buildings like that frequently have really long wiring runs. So I would say most of the time, these "208" voltage levels are reported as in the mid 190's. Mid 180's is on the lower end of what I see people mention, but still not that unusual. It would have been nice for them to have used thicker wire for this run to make less voltage drop, but it may not be necessary. I concur with @Big Earl that the thing to check on is to look at the voltage when it is first plugged in and then over the next couple of minutes as it ramps the current up to see if it drops quite a lot. The safety systems in the car will key off that too and kick down the amps if it sees a really big reduction there. But if it starts at like 189V without load and then only goes down to about 184V with charging amps running, then that's not a big deal.
 
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cantsingh

Member
Oct 7, 2019
26
4
DMV
Thanks guys, I should have clarified my question was more so about the unusual voltage than the actual charging rate. Glad to hear that it is not an issue and can be considered "typical" for large apartment buildings, and that I shouldn't expect it to damage my vehicle or the apartment / outlet itself.

I'll confirm the starting voltage and try plugging in at various different times to see if there is any rhyme or reason to it and report back.

PS - DMV is an acronym for the DC / Maryland / Virginia area. I guess it's not as well known as I thought!
 
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Rocky_H

Well-Known Member
Feb 19, 2015
6,441
7,667
Boise, ID
PS - DMV is an acronym for the DC / Maryland / Virginia area. I guess it's not as well known as I thought!
Reminded me of when someone asked some localized question about what was in the "GTA", with no explanation of where or what that was. Grand Theft Auto? General Transit Authority? Greater Toledo Area? Greater Tallahassee Area? Gainesville Transportation Administration? Regional acronyms are regional.
 

CharleyBC

Active Member
Jun 28, 2019
1,403
1,590
Talent, OR
PS - DMV is an acronym for the DC / Maryland / Virginia area. I guess it's not as well known as I thought!
Dang. And I used to live in NoVA (Northern Virginia), working there and in DC and MD. Missed that one! I thought maybe you were in another country where they have different line voltages. Sorry!

As dedicated a government employee as you might possibly be, I just couldn't picture you actually living in the Department of Motor Vehicles. :D
 

Sealander

Member
Oct 21, 2016
31
20
Houston North
If your actual supply voltage coming into the building is indeed 208, then your voltage drop is 25 volts and at 32 amps that is 800 watts being dissipated somewhere and I would certainly be concerned as that is going to produce a lot of heat somewhere particularly if it is at a connection point. Drop your charging current down to 10 amps and see what your voltage is then. If it goes up significantly that will tell you something about the quality of the connection and it would be safer until the problem can be identified.
 

Rocky_H

Well-Known Member
Feb 19, 2015
6,441
7,667
Boise, ID
If your actual supply voltage coming into the building is indeed 208, then your voltage drop is 25 volts and at 32 amps that is 800 watts being dissipated somewhere and I would certainly be concerned as that is going to produce a lot of heat somewhere particularly if it is at a connection point.
You're in a residential mindset. You're thinking of "somewhere" as being one place. It's not. 800 Watts heating up 200 feet multi-wire cable is a lot of thermal mass if this is just a really long wiring run in this apartment building where the panel is really far away. It's probably heating up the entire run of wire by just a few degrees.
 

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