What are these lockout clips called and how do I find one that will work with my breaker?
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Replacing 14-50 with HPWC, outlet on the wrong side of the stud
- Thread starter Glamisduner
- Start date
Tesla didn’t install a disconnect on mine. Dedicated 60 amp breaker in outside box, conduit runs outside the home, pops into garage and across garage width, drops down to HPWC. City inspector happy. This probably depends on jurisdiction?
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Disconnect is only required ABOVE 60 amps. A 60 amp 240V circuit does not require it.
60 amp breaker to HPWC does not require a disconnect. Since the wife just bought a Volvo, I doub't ill be buying another EV anytime soon, so I can probably just put in the 60 amp breaker and be good to go. It's not hard or expensive to change out breakers later should I need too.
I guess I'm not understanding what the new conduit layout is expected to be... I thought it was gonna become outside-the-wall, meaning a single 90 degree would be fine, going into the top of the HPWC.
It would look better to just get a new chunk of emt and bend it once at HD/Lowes than to try to cut the horizontal run of the current EMT. No big deal.
It would look better to just get a new chunk of emt and bend it once at HD/Lowes than to try to cut the horizontal run of the current EMT. No big deal.
The current piece of conduit has 3 or 4 bends. A 90 to bend it towards the wall, A 90 to go down the wall, and then a bend to go into the wall, and then another bend to straighten it out. I was planning to cut it after the second 90, to remove the bend going into the wall and the other to straighten it out within the wall. Not sure if they will be able to replicate the first 2 90's such that it will come straight down my wall?
Ah, I was missing that there's another 90 before the one that turns it down the wall,,,,
Sure, cutting it after the second 90 and adding a short straight line down the outside of the wall sounds good. You might even be able to use the remainder of the straight pipe thats still in the wall if you don't mind moving the HPWC up a few inches. EMT isn't real expensive anyway.
So I'm wrapping things up and just need to decide on which breaker to use. Wire is 4awg THHN.
According to this chart, http://www.usawire-cable.com/pdfs/nec ampacities.pdf
It looks like It should be good for 95 amps continuous. But that seems wrong to me? I might just put in a 60 amp breaker and be done with it since the 3 maxes out at 48 amps.. I think 4awg can support a 90 amp breaker but I'm not sure?
Anyone have access to the code book? I found a copy online but I don't want to pay $100 for it.
I'll probably just put in the 60 amp breaker for now and set the charger to 48 amps. I only have the 4 and that's a decent charge rate even if I had an S? Breakers are easy to replace later should I get another tesla? Pretty sure 4awg is good for an 80 amp breaker and a charge rate of 64 amps though. No sure if it is actually good for 95 amps as I don't know what the * rating is for. Also the wire runs through conduit in my attic which can be pretty hot in the summer?
This chart suggests an 80 amp breaker for 4awg and a 64 amp setting on the HPWC.
Chart of Wiring/Breaker/Conduit for Tesla Wall Connector
But I still don't know where to buy an 80 amp breaker with a lockout.
According to this chart, http://www.usawire-cable.com/pdfs/nec ampacities.pdf
It looks like It should be good for 95 amps continuous. But that seems wrong to me? I might just put in a 60 amp breaker and be done with it since the 3 maxes out at 48 amps.. I think 4awg can support a 90 amp breaker but I'm not sure?
Anyone have access to the code book? I found a copy online but I don't want to pay $100 for it.
I'll probably just put in the 60 amp breaker for now and set the charger to 48 amps. I only have the 4 and that's a decent charge rate even if I had an S? Breakers are easy to replace later should I get another tesla? Pretty sure 4awg is good for an 80 amp breaker and a charge rate of 64 amps though. No sure if it is actually good for 95 amps as I don't know what the * rating is for. Also the wire runs through conduit in my attic which can be pretty hot in the summer?
This chart suggests an 80 amp breaker for 4awg and a 64 amp setting on the HPWC.
Chart of Wiring/Breaker/Conduit for Tesla Wall Connector
But I still don't know where to buy an 80 amp breaker with a lockout.
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The ampacity of wire is determined by its heat rating and other factors. Many wire types are physically rated at 90C, but the conditions of use don't allow you to use the full 90C rating in many cases. Residential breakers are rated at 75C, so you cant use a wire temperature rating that is higher than the point of termination allows. If that wire is a multi-conductor bundle with its own sheath like Romex, or SER, then its rating will be listed on the jacket. Romex is usually 60C and SER is 75C.
So if you ran individual #4 THHN conductors from a breaker to a HPWC in EMT, and there are no other conductors in that conduit, then the rating of #4 copper is 85A at 75C.
If those THHN conductors are part of a Romex type bundle, and the bundle is rated at 60C then the wiring is good for 70A.
Since a single model 3 tops out at 48A I'd just put in a 60A breaker. If you have any desire to add another HPWC in the future, then I'd consider setting myself up for that now with a larger breaker as appropriate.
NeverFollow
Active Member
I use this web site to calculate my wires size: Build My Own Cabin
I would recommend you download this excel spreadsheet
Voltage Drop Calculator as you can include the length of your line.
- For 95A, AWG3 is recommended for up to 149 ft.
Also the following chart can be useful: Ampacity Charts - Wire Size & Amp Ratings
- It seems that 4 AWG is rated 70A(60°C) / 85A(75°C ) / 95(90°C)
Some additional code information: PG&E: Code Requirements for Installing EVSE.
4awg thhn is 90c wire. Sounds like i would be safe with an 80amp breaker? run is about 100ft.
at home Depot right now and they don't have 80amp breakers, only 70s
I can order this but not sure what to do for a disconnect? Eaton BR 80 Amp 2 Pole Circuit Breaker-BR280 - The Home Depot
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See my post above, regardless of the wire temperature rating, the temperature of the whole circuit is based on the lowest temperature equipment, in this case the breaker. Since the breaker is rated at 75C the wire must be treated as 75C wiring. Therefore 85A for the circuit, and fine for either 80 or 70A breaker. Voltage drop is about 1.7% for that 100 ft run of #4 at 64A continuous on an 80A breaker.
eprosenx
Active Member
At dinner now, but the bottom line is I would do one of two things:
60a breaker, no locking clip.
80a breaker, with locking clip (the clip is not part of the breaker, it just sits on top of the breaker generally).
I can run all the math when I get back home to tell you what temps in the attic will be acceptable, but I am not worried. The wire is rated to 95 amps at its 90c insulation rating. While we can only use the 85a rating of the wire due to the 75c terminal limitation of the breaker and wall connector, we still can use that 90c limit for calculating temperature limits in your attic. So I am sure you are fine.
Either solution is totally fine as long as you set the Wall Connector to match via the rotary dial.
60a breaker, no locking clip.
80a breaker, with locking clip (the clip is not part of the breaker, it just sits on top of the breaker generally).
I can run all the math when I get back home to tell you what temps in the attic will be acceptable, but I am not worried. The wire is rated to 95 amps at its 90c insulation rating. While we can only use the 85a rating of the wire due to the 75c terminal limitation of the breaker and wall connector, we still can use that 90c limit for calculating temperature limits in your attic. So I am sure you are fine.
Either solution is totally fine as long as you set the Wall Connector to match via the rotary dial.
NeverFollow
Active Member
You have to consider the total Ampacity of your main panel and evaluate the typical load of your home will charging.
If you charge at night, you might not have too much load, except possible the Air Conditioning.
For the 95A usage case, It might be safe then to install a disconnect box to de-energizes the charger
when the total load exceed 80% of the total power consumption of the main panel.
eprosenx
Active Member
We have not run an official load calculation on this install (actually we have not even seen a picture of his panel - I would still like to see a picture of the panel for reference), but I suspect that the 80a setting will be OK. He just upgraded from a 100a service to a 200a service since an AC unit may have pushed him over the load limit. There is a good chance that he already had some remaining capacity on the 100a service, so as long as the AC unit is not some massive beast he will be OK.
Also, if there was any load calculation issue he could still breaker it at 80a on the 4awg in conduit, but set the rotary dial to something lower in order to stay under the load calculation. Then later if he say swapped an electric water heater to gas he could go back and up the Wall Connector to the full 80 amps once there was more calculated load capacity available. (he could also buy something like a Sense Energy Monitor and profile his usage over a year and use it to prove the full 80a / 64 amps was fine based on actual load).
I would not consider a load shedding box to monitor usage and de energize if it exceeded 80%. There is just no reason to in this situation. Worst case the OP just has to set the wall connector to 60 amps (regardless of if it is a 60/70/80a breaker). He still will charge at full speed on a 3. I am sure his AC doesn’t not count for more than 40a of calculated load.
Oh I thought I posted a picture of my panel but here it is again. Only changes are the 20amp 240v was changed to a 30 (I was charging off this for my volt).
And then we added the 14-50 and then I changed this to a wall connector (60 amp breaker).
I plan to get a timer for our water heater and shut it off at night and turn it on before we get up so really only the car and AC would be on (AC is 30 amp breaker). Maybe the dryer but it's really only 20 amps but we can pretend 30.
So 30 for AC, 30 for water heater, 30 for dryer, and 80 I should still be ok as long as I'm not doing all that AND cooking at midnight I should be ok!
So I went with the 60 amp breaker for now, I don't know where to get one of those lockout devices and Lows / Home Depot only sell 60, 70, 100 and 125's. But the hard part is finding the lockout / disconnect that will work with my breakers?
Anyways here's what I did to mount it. I used 4" lag bolts instead of the provided wood screws, and used lag bolts to attach the 2x4 too. I used an inch lbs screw driver I bought when doing some gun smithing to tighten down the wires. They took quite a bit of torque 35 inch/lb for the top buss, and 33 for the block on the HPWC and 18 inch/lb for the ground.
Cut some new drywall (never really done this before but it came out ok.
And it works!
And then we added the 14-50 and then I changed this to a wall connector (60 amp breaker).
I plan to get a timer for our water heater and shut it off at night and turn it on before we get up so really only the car and AC would be on (AC is 30 amp breaker). Maybe the dryer but it's really only 20 amps but we can pretend 30.
So 30 for AC, 30 for water heater, 30 for dryer, and 80 I should still be ok as long as I'm not doing all that AND cooking at midnight I should be ok!
So I went with the 60 amp breaker for now, I don't know where to get one of those lockout devices and Lows / Home Depot only sell 60, 70, 100 and 125's. But the hard part is finding the lockout / disconnect that will work with my breakers?
Anyways here's what I did to mount it. I used 4" lag bolts instead of the provided wood screws, and used lag bolts to attach the 2x4 too. I used an inch lbs screw driver I bought when doing some gun smithing to tighten down the wires. They took quite a bit of torque 35 inch/lb for the top buss, and 33 for the block on the HPWC and 18 inch/lb for the ground.
Cut some new drywall (never really done this before but it came out ok.
And it works!
eprosenx
Active Member
Great job! Way to stick with it! Just be sure you set the rotary dial right since you have no way to test currents above 48 amps without a higher power charger Tesla (or special test gear).
And good job even using a torque screwdriver! I have been wanting to get one.
I am confused on the main panel picture:
Is the 30a top breaker I can’t read where you now have the 60a breaker for the Wall Connector?
eprosenx
Active Member
FYI, the Eaton part number you want to be able to lock off a BR style breaker is "BRLW". Home Depot stocks them as "BRLWCS" I think, which means it comes in a retail clamshell packaging.
Eaton BR Type Handle Lockout-BRLWCS - The Home Depot
They also make BRLW2 which is "handle mounted". I am less familiar with these. They may not be as permanent and so perhaps they don't count? I am guessing these are for maintenance techs that need to lock off a breaker to do some work on a piece of equipment but without requiring the "hot work" to remove the panel cover. I don't think Home Depot stocks these.
If you needed the lockoff, I would just go with the BRLW from Home Depot.
But since you went with a 60a breaker, you don't need it, so don't worry about it!
Nice job again!
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