UMC Standby Power Consumption?

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96s46p

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#1
Has anyone measured the standby power consumption of the UMC? I just noticed it was warm (120° F ) when it wasn't connected to the car. Is it better to plug/unplug it at the 14-50 side or the UMC side of the adapter?
 

PNWmisty

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#2
Has anyone measured the standby power consumption of the UMC? I just noticed it was warm (120° F ) when it wasn't connected to the car. Is it better to plug/unplug it at the 14-50 side or the UMC side of the adapter?
It doesn't take much standby draw to heat a small object that much. Of course, if you disconnect on the outlet side of the UMC there will be no drain.
 

garsh

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#3
Has anyone measured the standby power consumption of the UMC?
@Mike inadvertently measured the standby power of a Wall Connector. It's probably similar. :)

You are correct @garsh, I just re-ran the experiment without the Tesla Wall Connector attached to the car and the reading is the same......so my wall connector uses 12 watts.
 

96s46p

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#4
Interesting, 12W seems like too much to keep the electronics powered up.

Well both connections are upstream of the UMC, unplugging the adapter from the wall or the adapter from the UMC.
 

garsh

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#5
I'll have some measurements made of the mobile connector when I eventually get my car. I already have a TED measuring that circuit.
 

tivoboy

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#6
I took a bunch of readings at the meter only for charging and the umc after charging and unplugged from the car. It was negligible at about .05 watt. I usually unplug it though at the dryer buddy must because I don’t use it often enough and don’t like just leaving things plugged in all the time if they are only needed once a week at most.
 

KFORE

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#7
My CT clamps around my charging circuit measure 0.7 Watts while the UMC is plugged in. Not enough to worry about or matter in terms of electricity cost.
 

96s46p

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#8
Interesting, at <1w I don't think it should be generating that much heat though
 

JWardell

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#9
I measured my UMC at standby at 2W @120V. Wasn't thrilled with that. Bright LED I guess!
 

96s46p

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#11
How are you guys measuring? If it is with 50A CT then I don't think 10W range measurements are accurate.
 

Mike

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#16
When I'm back from my first long distance road trip later tonight, I'm installing what will essentially be a "Hobbs counter" for my wall connector circuit.

It will measure voltage and amperage so I know the standby drain.......