Circuit for for RV pedestal (now) and possible future EV

[75gmck25]

I want to run 6/3 copper cable (or individual wires in conduit) through my basement, from the main panel over to the other side of the house (30-40 feet), through the wall, and then mount one of the RV (or temporary power ) boxes on the exterior wall of the house. Most of these boxes provide a 20 amp GFCI receptacle, a 14-50, 50 amp 240 volt receptacle, and a 30 amp RV receptacle. I would use the 20 amp circuit for battery chargers, etc., and in the future want to use the 14-50 for a welder or for a plug-in EV charger. I don't currently have either a welder or RV charger, so those are future needs.

What confuses me a little is that the 14-50 receptacle is rated for 50 amps. If I plugged in an EV charger, some of them I've found draw up to 48 amps and the installation specs require a 50 amp breaker. If they are considered a 48 amp continuous load, don't you need a 60 amp circuit? Or maybe I don't understand the requirement.

Another option is to run #4 or larger cable to an exterior sub panel, and then install the temp/RV power box off that sub panel. However, then my cable costs go up a lot (unless I go to AL conductors), and it's harder to route it through the basement (bigger holes drilled in the joists, and/or use larger conduit).

 

[dcg9381]

What confuses me a little is that the 14-50 receptacle is rated for 50 amps. If I plugged in an EV charger, some of them I've found draw up to 48 amps and the installation specs require a 50 amp breaker. If they are considered a 48 amp continuous load, don't you need a 60 amp circuit? Or maybe I don't understand the requirement.

EVSE:
They're rated for 48A if "hard wired" and likely require a 60A residential breaker due to the 80% continuous use rating.
You'll find that the other typical rating is 42A, which is what you want if you're pulling it into a 14-50R on a 50A breaker.

Another option is to run #4 or larger cable to an exterior sub panel, and then install the temp/RV power box off that sub panel. However, then my cable costs go up a lot (unless I go to AL conductors), and it's harder to route it through the basement (bigger holes drilled in the joists, and/or use larger conduit).

I love to recommend these - look at "Siemens Talon" as a box for this. They have everything built in you want and are usually under $250.

6/3 copper is around $7 foot currently. You can do 90A of 2-2-2-4 MHF for a lot less - yep, it's bigger.

 

[mike93lx]

If you run conduit end to end, I would look at #4 AL xhhw. No need to use MHF unless you are going direct burial.

 

[75gmck25]

I still need to figure out what size of conduit I can use end to end. There is a soffit I can run through across the top of basement wall and I know it's big enough for 1" PVC conduit, but I think it would be tough to fit anything larger unless I use EMT (maybe 1 1/4"). And my skills at bending and fitting EMT are a little rough.

If I pulled individual conductors for 2-2-2-4 AL, and had two 90 degree bends, what is the recommended conduit size? Calculators seem to show that it would fit in 1" conduit, but that really seems small.

 

[mike93lx]

I still need to figure out what size of conduit I can use end to end. There is a soffit I can run through across the top of basement wall and I know it's big enough for 1" PVC conduit, but I think it would be tough to fit anything larger unless I use EMT (maybe 1 1/4"). And my skills at bending and fitting EMT are a little rough.

If I pulled individual conductors for 2-2-2-4 AL, and had two 90 degree bends, what is the recommended conduit size? Calculators seem to show that it would fit in 1" conduit, but that really seems small.

1.25" min, won't be fun. Definitely not 1"

That's assuming xhhw.

If you are stuck with 1", #6 copper thwn will be fine. #4 AL is probably ok

 

[dcg9381]

I still need to figure out what size of conduit I can use end to end.

EMT:

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PVC:

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Electrical Supplies Distributor. Elliott Electric Supply is your local electric supply house. We Deliver Lower Cost, Quality Products, and Personal Service

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[mm08822]

If you can run 1" emt end-end, you won't have to pull a seperate grd. You could pull 4-4-6 AL XHHW. This will cover a 48A continuous EV charger load.

 

[75gmck25]

Thanks for all the info.

I need to open up the soffit and figure out how much space I have for the new conduit. The soffit was boxed in around an iron gas pipe that ran across about 5 " below the floor joists, so that should have left a good sized space above it to fit the electrical conduit. However, I wasn't there when they framed the soffit, so it's hard to tell how much wood might be in the way.

 

[dave*99]

I've had good luck shoving a penlight and my cell phone (camera) into those spaces before cutting holes. Tape a string to the phone in case you drop it.
I have an endoscope camera that connects to a laptop too. Now Amazon sells endoscope cameras that connect to cell phones.

 

[75gmck25]

I posted earlier about my plan to use an RV pedestal (probably Siemens Talon) to provide a 14-50 receptacle for an EV charger, and also a 20 amp 120 volt receptacle for general use. It's a standard commercial product, and easy to buy. Its kind of big and unsightly on the side of the garage, but I figured I could work around that.

I then picked out a ChargePoint EV charger unit as an example, so I could look at the installation instructions. Its manual says that if you buy the plug-in version it will only have a one foot cable, and this is the max allowed by the electrical code. If you want to have a longer cable you can buy a hardwire kit and replace the plug assembly with a longer cable assembly for hardwire (looks like an A/C compressor whip). This is the link to the instructions. https://images.thdstatic.com/catalog/pdfImages/52/52975f33-5dfe-4783-9696-5fe8da51ef31.pdf

This is what I'm trying to figure out for plug in.
- The RV pedestal is designed for the cable to be plugged in all time, and it shields the plugged-in cables by routing them down through a slot in the bottom of the front edge of the box so it is out of the rain.
- The Chargepoint unit also has the plug-in cable running straight down from the unit, and as I already mentioned, it's only one foot long.
I don't think the plug-in cable is really long enough to make a 180 degree loop and plug into the RV pedestal unless they are nearly touching each other. Or am I misinterpreting something?

If I buy the hardwire kit it will be simpler to wire the EV charger to 240 volts, but I lose the 120/240 capability provided by using the RV pedestal (which is really designed more like a small sub-panel). Another alternative is to add a small exterior-rated sub-panel on the outside of the garage, and then use conduit to connect circuits for 240 volt and 120 volt receptacles that have in-use covers.

If someone else has gone through this analysis, I'd appreciate any input.

 

[theoldwizard1]

That's assuming xhhw.

#6 copper XHHW is $1.03/ft. THHN is $0.86

If you are stuck with 1", #6 copper thwn will be fine. #4 AL is probably ok

#4 aluminum XHHW is $0.29/ft. THHN is $0.60/ft. (???!!!!)

 

[mike93lx]

I posted earlier about my plan to use an RV pedestal (probably Siemens Talon) to provide a 14-50 receptacle for an EV charger, and also a 20 amp 120 volt receptacle for general use. It's a standard commercial product, and easy to buy. Its kind of big and unsightly on the side of the garage, but I figured I could work around that.

I then picked out a ChargePoint EV charger unit as an example, so I could look at the installation instructions. Its manual says that if you buy the plug-in version it will only have a one foot cable, and this is the max allowed by the electrical code. If you want to have a longer cable you can buy a hardwire kit and replace the plug assembly with a longer cable assembly for hardwire (looks like an A/C compressor whip). This is the link to the instructions. https://images.thdstatic.com/catalog/pdfImages/52/52975f33-5dfe-4783-9696-5fe8da51ef31.pdf

This is what I'm trying to figure out for plug in.
- The RV pedestal is designed for the cable to be plugged in all time, and it shields the plugged-in cables by routing them down through a slot in the bottom of the front edge of the box so it is out of the rain.
- The Chargepoint unit also has the plug-in cable running straight down from the unit, and as I already mentioned, it's only one foot long.
I don't think the plug-in cable is really long enough to make a 180 degree loop and plug into the RV pedestal unless they are nearly touching each other. Or am I misinterpreting something?

If I buy the hardwire kit it will be simpler to wire the EV charger to 240 volts, but I lose the 120/240 capability provided by using the RV pedestal (which is really designed more like a small sub-panel). Another alternative is to add a small exterior-rated sub-panel on the outside of the garage, and then use conduit to connect circuits for 240 volt and 120 volt receptacles that have in-use covers.

If someone else has gone through this analysis, I'd appreciate any input.

If the evse is going to stay there, why not just hardwire it? What 120/240 capability do you lose?

I think I would do a small subpanel, Hardwire the evse and install a 120v receptacle.

A 4-space should be about $50) don't forget a ground bar, too).

 

[75gmck25]

The 4-space sub panel looks like the most flexible choice, and I can either hardwire the EV charger or add an in-use 240 volt receptacle for a plug-in EV charger. I like this alternative because I can also add the breaker for a 120 volt GFCI receptacle to use for a vacuum cleaner, power washer, or whatever else I use to clean up the car and driveway.

Thanks again.

 

[dcg9381]

Those Siemens Talons are great panel options.. I've got 5 of them. I use them all over the place. You can plug into them native or run a hardwired EVSE surface mount.

 

[dave*99]

I posted earlier about my plan to use an RV pedestal (probably Siemens Talon) to provide a 14-50 receptacle for an EV charger, and also a 20 amp 120 volt receptacle for general use. It's a standard commercial product, and easy to buy. Its kind of big and unsightly on the side of the garage, but I figured I could work around that.

I then picked out a ChargePoint EV charger unit as an example, so I could look at the installation instructions. Its manual says that if you buy the plug-in version it will only have a one foot cable, and this is the max allowed by the electrical code. If you want to have a longer cable you can buy a hardwire kit and replace the plug assembly with a longer cable assembly for hardwire (looks like an A/C compressor whip). This is the link to the instructions. https://images.thdstatic.com/catalog/pdfImages/52/52975f33-5dfe-4783-9696-5fe8da51ef31.pdf

This is what I'm trying to figure out for plug in.
- The RV pedestal is designed for the cable to be plugged in all time, and it shields the plugged-in cables by routing them down through a slot in the bottom of the front edge of the box so it is out of the rain.
- The Chargepoint unit also has the plug-in cable running straight down from the unit, and as I already mentioned, it's only one foot long.
I don't think the plug-in cable is really long enough to make a 180 degree loop and plug into the RV pedestal unless they are nearly touching each other. Or am I misinterpreting something?

If I buy the hardwire kit it will be simpler to wire the EV charger to 240 volts, but I lose the 120/240 capability provided by using the RV pedestal (which is really designed more like a small sub-panel). Another alternative is to add a small exterior-rated sub-panel on the outside of the garage, and then use conduit to connect circuits for 240 volt and 120 volt receptacles that have in-use covers.

If someone else has gone through this analysis, I'd appreciate any input.

Interesting items in the manual.... And it's probably irrelevant since you plan to plug it in. But for anyone considering hardwiring... good to know this stuff.

Page 2 says:



Would that be for hardwired applications?


And it also says the internal wiring terminals are rated for 105 C and 6 gauge wire.