TomMoloughney
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Re: Which Home Charging Station Do You use?

Thu May 10, 2018 7:18 am

Nyken wrote:I'm using a Juicebox Pro 40. I have a Nema 14-50 outlet installed in the garage, with the Juicebox Pro plugged into it.

I consider the Nema 14-50 outlet to be the 'standard' for EVSE equipment. You would need a good reason NOT to install a 14-50 outlet.

The Nema 14-50 and the wire from the electric panel in the basement it is sized for 50 amps. The i3 will consume 32 amps max while charging. And the Juicebox Pro is limited to 40 amps max.

With EVSE equipment, you need to size the circuit breaker in your electric panel to the car max charging rate of your car +25% (the +25% is needed to protect an electrical circuit which is on continuously, like a car charger or an electric heater). In the case of the i3, this is 32amps x 1.25 or 40 amps.

So in my case, even though I have 50amps max at the Nema 14-50 outlet, I have a 40amp circuit breaker protecting this equipment. In the future, if I get a car which could charge at 40amps, I'd simply swap out the 40 amp circuit breaker for a 50 amp breaker.
It's not as simple as just upgrading the circuit breaker, and I assume you realize that. I just want to make sure other readers don't get the wrong idea. In addition to the new circuit breaker, the wiring has to be sized properly also. You'll need 8 gauge wiring for a continious 40 amp draw. A circuit that was wired for a 30 amp draw may have 10 gauge wiring, which is insufficient if you upgrade to a 40 amp EVSE.
Tom Moloughney
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viking79
Posts: 110
Joined: Wed Apr 16, 2014 3:04 pm

Re: Which Home Charging Station Do You use?

Thu May 10, 2018 8:02 am

I use a Clipper Creek HCS40 and a ChargePoint Home. Both are 32 amp (use 40 amp breakers with 8 gauge wiring). I generally charge the i3 with the Clipper Creek and the Clarity with the ChargePoint, just so I can track how much energy I am using for the Clarity. I have a basic power meter (hall effect sensor) hooked up for my HCS40 measuring power to that unit as well.

I love both chargers. The Clipper Creek for its simplicity and reliability and the ChargePoint for the wifi and logging. Both function excellently.

I prefer hardwired. Less prone to damage, less space. It is also easy to unhook and move just by shutting down breaker before disconnecting it.

SSi3
Posts: 256
Joined: Mon Sep 15, 2014 7:55 am
Location: Ontario, Canada

Re: Which Home Charging Station Do You use?

Fri May 11, 2018 9:03 am

I have a FLO X5, which has been good, pricey but solid, outdoor-rated and wifi connected... happy with it!
Born electric 4/25/15 (2015 REx)
Re-born fully electric 7/27/19 (2019 i3s BEV)

Nyken
Posts: 32
Joined: Sun Apr 29, 2018 3:44 am
Location: New York

Re: Which Home Charging Station Do You use?

Fri May 11, 2018 3:49 pm

"It's not as simple as just upgrading the circuit breaker, and I assume you realize that. I just want to make sure other readers don't get the wrong idea. In addition to the new circuit breaker, the wiring has to be sized properly also. You'll need 8 gauge wiring for a continious 40 amp draw. A circuit that was wired for a 30 amp draw may have 10 gauge wiring, which is insufficient if you upgrade to a 40 amp EVSE."

I used 8g THHN wire for the 14-50 plug. It's good to 50amp, which when derated by 25%, means it will support a 40amp charger.

See this chart:
https://www.cerrowire.com/ampacity-charts

I'm not an electrician, but I've always gone with the following order of presidence: equipment, plug, wire, breaker. First determine the equipment you want to power, then figure out which plug you'll need (there are a dozen different plugs available with different power/voltage ratings), then figure out the gauge of wire needed for the plug, and finally which circuit breaker you need to protect the wire. I started with the Juicebox 40 which needed 50amps.
2017 i3 Rex, Juicebox Pro 40

RonR
Posts: 4
Joined: Fri May 11, 2018 5:34 pm

Re: Which Home Charging Station Do You use?

Fri May 11, 2018 5:41 pm

I have a ChargePoint 30A (hardwired) EVSE. You can use the ChargePoint smartphone app to manage it. Well made, very happy with it.

Ron
2015 BMW i3, Arravani Grey

viking79
Posts: 110
Joined: Wed Apr 16, 2014 3:04 pm

Re: Which Home Charging Station Do You use?

Sat May 12, 2018 5:58 am

Nyken wrote:"It's not as simple as just upgrading the circuit breaker, and I assume you realize that. I just want to make sure other readers don't get the wrong idea. In addition to the new circuit breaker, the wiring has to be sized properly also. You'll need 8 gauge wiring for a continious 40 amp draw. A circuit that was wired for a 30 amp draw may have 10 gauge wiring, which is insufficient if you upgrade to a 40 amp EVSE."

I used 8g THHN wire for the 14-50 plug. It's good to 50amp, which when derated by 25%, means it will support a 40amp charger.

See this chart:
https://www.cerrowire.com/ampacity-charts

I'm not an electrician, but I've always gone with the following order of presidence: equipment, plug, wire, breaker. First determine the equipment you want to power, then figure out which plug you'll need (there are a dozen different plugs available with different power/voltage ratings), then figure out the gauge of wire needed for the plug, and finally which circuit breaker you need to protect the wire. I started with the Juicebox 40 which needed 50amps.
JuiceBox requires 6 AWG wire for 50 A, but maybe they allow smaller for THHN wire?

https://support.emotorwerks.com/hc/en-u ... _site=true

They word it weird, but NEC seems to show that 8 gauge THHN should be all right for that current.

Sorry, edited a couple times

Powerfool
Posts: 6
Joined: Thu May 10, 2018 4:50 am

Re: Which Home Charging Station Do You use?

Fri May 18, 2018 10:25 am

So I am considering the JuiceBox. Is there really any significant benefit to the Pro versus the Lite?

I have a 60 amp circuit and have wired up the NEMA 14-50 outlet... so now I just need to pick a charger. From what I read, they both have WiFi connectivity and the app can connect to them... the Pro stores data whereas the Lite doesn't? Doesn't seem like a huge difference to me.
2015 BMW i3 REx Ionic Silver, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, Harmon/Kardon Premium Sound, Sport 20" Alloy Wheels

Nyken
Posts: 32
Joined: Sun Apr 29, 2018 3:44 am
Location: New York

Re: Which Home Charging Station Do You use?

Sat May 19, 2018 3:50 am

JuiceBox requires 6 AWG wire for 50 A, but maybe they allow smaller for THHN wire?

https://support.emotorwerks.com/hc/en-u ... _site=true

They word it weird, but NEC seems to show that 8 gauge THHN should be all right for that current.
NM-B wire has its amperage derated due to the extra heat generated by wires being bundled together. With THHN wire in a 1" conduit, they are spread apart more and are cooled by the air space between the wires.

I used 8# THHN wire, which are individual wires, running through 1" conduit. I could have used NM-B wire, which is a wire bundle, but I would have needed 6 gauge wire.

So, I guess JuiceBox suggests 6# wire assuming NM-B is used and the load (car charger) will be 40 amps continuous. If I didn't need conduit, I would have used NM wire which is easier to work with.
2017 i3 Rex, Juicebox Pro 40

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