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How can I tell what capability the Service Lateral has?

EVer Hopeful

Active Member
Jul 7, 2021
1,165
900
Texas
My panel is 150A, but that's just the panel. Maybe that's all they had on the truck when they installed it twenty years ago.

Can I tell from looking at the service entry cable size if it could have been higher? I figured maybe if I looked I could tell whether it was 0 or 1/0, 2/0 etc


I think I've just answered my own question: I have Cu coming into the house (well from the meter to the house), so to upgrade to 200A, I'd need 2/0

1660133851791.png


Reference: Electrical Service Entry Wire Inspection & How to Determine Electrical Service Ampacity: How to Inspect (and I'm sorry about all the adverts)

also: Electrical wire sizes & Diameters, Wire Size Tables for Normal & Long Wire Runs (use a plastic caliper - lol)



Here's the SEC in the panel

1660134152930.png
 
It doesn't look like 2/0 to me, but hard to tell from a picture. Very rarely will anyone run the SE cable any higher than the panel they're putting in. You also have to know what they're running from the XFMR to your meter. Pretty sure you're stuck at 150A, which was a popular SE sizing back then. You could measure the OD, and go to the store and measure what they have there. As long as it's the same type of course. Kind of looks like USE cable to me, but could be THHN.

The bigger question is do you need 200A. Upgrading a panel is a pain, even if you don't get it inspected, which you should. Believe me, I've done it. But I had to upgrade, I have an electric WH, stove, dryer, and only had a 100A panel. Wasn't enough if I used all of those and charging at once.
Depending on what you have, 150A should be enough to throw in a 40 or 50 amp charging circuit no problem. Unless you're driving the full range everyday. I installed a 60A circuit, but soon realized that was overkill. I only charge at 20-25 amps depending on season. Higher than that starts to create a lot of waste heat I've found. The difference between recharging in 4 hours vs. 7 hours doesn't really gain you anything. Either way that's too slow if you're in a hurry, and you're better off heading to the nearest SC if you need to top up quickly.
 

qdeathstar

Completely Serious
May 17, 2019
4,590
4,730
VB
That said that panel has… issues.

There is no bushing on the conduit running the service wires into the panel. Also, the conduit appears to be metal but it isn’t bonded. A 2” Romex connector is not rated for numerous 12-2 Romex cables. Those cables should be installed in separate connectors. The panel is missing it’s bonding screw which bonds the can of the panel to the neural as it appears to be a service panel. There is no anti-oxide compound installed on the aluminum connections. Numerous double tapped wires.
 

EVer Hopeful

Active Member
Jul 7, 2021
1,165
900
Texas
thanks for the replies (and I wish I'd not asked now 😪 )

It was an idle question which I see to my embarrassment I've asked here before (sort of). I set the HPWC to 30A because like was mentioned, why go higher? I sleep all night long so have more then 8 hours to put the electrons back into the car. A Load Calculation makes that a no-brainer anyway

qdeathstar - thanks for the pointers. Not sure what I can do about them at this point
 
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qdeathstar

Completely Serious
May 17, 2019
4,590
4,730
VB
thanks for the replies (and I wish I'd not asked now 😪 )

It was an idle question which I see to my embarrassment I've asked here before (sort of). I set the HPWC to 30A because like was mentioned, why go higher? I sleep all night long so have more then 8 hours to put the electrons back into the car. A Load Calculation makes that a no-brainer anyway

qdeathstar - thanks for the pointers. Not sure what I can do about them at this point

My suggestion would be to have a liscensed electrician give you an estimate for repairs. You should be about to find a reputable one that would do so for free. Expected to pay between $2000-$4000

The most dangerous thing on the list I gave you was lack of bonding to the panel and feeder conduit. Those two things can definitely start a fire so I would really recommend doing at least those. Shouldn’t have to replace the panel to address those, but you might find a hard time finding an electrician willing to just do those two things…
 
No problem, a lot of people, myself included, wondered what do I really need to do in my situation.
If you get another EV, then maybe upgrade to 50 or 60A. But if you already have a 50A circuit to your HPWC, add another HPWC that can load share with the other. 20A per vehicle should still be enough overnight.
And if it's at night, your other electrical loads are likely to be lower anyway, so pulling 30-40% of your panel capacity for charging shouldn't cause troubles.

As qdeathstar pointed out, updating/repairing your panel, even if same amperage wouldn't be a bad idea. The aluminum wire bothers me, but that would be really expensive to upgrade. It's why all of my wiring projects use conduit. Much easier to change wire if needed. No need to rip walls off!
If the electrician is just fixing mistakes in that panel, it should be pretty cheap. Replacing the whole thing, yeah, $2-4K like he said. Especially since everything will have to be $50 GFCI/AFCI breakers. Which isn't a bad idea, especially with AL wire.
 

qdeathstar

Completely Serious
May 17, 2019
4,590
4,730
VB
You don’t need to put gfci/afci in the panel if you are replacing it, at least here. But rules might be difference elsewhere depending on ahj.

For the aluminum in leu of a full rewire id suggest alumicon connectors (not purple wire nuts….figure on 5-6k for that.
 
You don’t need to put gfci/afci in the panel if you are replacing it, at least here. But rules might be difference elsewhere depending on ahj.
True, I want so say here any modification to a circuit in that location needs to be brought up to code. I had to when upgrading my panel. A good question for your AHJ for sure.
But, I would install them anyway if you're going through all the trouble/cost to update the panel. Especially on a building with older wire.
 

qdeathstar

Completely Serious
May 17, 2019
4,590
4,730
VB
True, I want so say here any modification to a circuit in that location needs to be brought up to code. I had to when upgrading my panel. A good question for your AHJ for sure.
But, I would install them anyway if you're going through all the trouble/cost to update the panel. Especially on a building with older wire.
It does sound tempting especially for aluminum. On the other hand, Older 14-3 is not compatible with arc fault breakers because it can create inductance on the lines because the conductors are wrapped around each other. This looks like an arc to the breaker so the breaker will trip. But that was the story when arc fault breaks first came out, circuitry and software might be different now.
 
It does sound tempting especially for aluminum. On the other hand, Older 14-3 is not compatible with arc fault breakers because it can create inductance on the lines because the conductors are wrapped around each other. This looks like an arc to the breaker so the breaker will trip. But that was the story when arc fault breaks first came out, circuitry and software might be different now.
Interesting, I hadn't thought of that. I haven't dealt with any of that old wire on AFCI yet. The wire running to where my above range microwave is supposed to go uses old cloth wrapped round wire. When they re-wired the house they forgot about replacing that one I guess. I'm not using it though because it's coming from my living room circuit, which also serves the bedrooms. Can't believe they didn't divide that up while they were running new wire up in the attic anyway. Kitchen needs a serious remodel, so I'll make the microwave a dedicated circuit when that happens.
 

qdeathstar

Completely Serious
May 17, 2019
4,590
4,730
VB
Interesting, I hadn't thought of that. I haven't dealt with any of that old wire on AFCI yet. The wire running to where my above range microwave is supposed to go uses old cloth wrapped round wire. When they re-wired the house they forgot about replacing that one I guess. I'm not using it though because it's coming from my living room circuit, which also serves the bedrooms. Can't believe they didn't divide that up while they were running new wire up in the attic anyway. Kitchen needs a serious remodel, so I'll make the microwave a dedicated circuit when that happens.

That microwave used to be an hood fan which only drew an amp… probably need a new 20 amp circuit dedicated for the microwave
 

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