Water Heater Control

[Volta]

Why not? That's what the water heater does, leaving both the upper and lower elements 1/2 live at all times.

I think that the wires within the appliance would be considered differently than building wires.

But I also feel it would be compliant to break only one leg for the control.

 

[travisw]

I don't think that you can use a switch that only breakes one side of the circuit if it has an on and off position.

404.15 B Off Indication. Where in the off position, a switching device with a marked OFF position shall completely disconnect all ungrounded conductors to the load it controls.

 

[dbuckley]

404.15 B Off Indication. Where in the off position, a switching device with a marked OFF position shall completely disconnect all ungrounded conductors to the load it controls.

Thats a great find!

To misquote - Two pole switches - they're not just a good idea, they're the law!

 

[hillbilly1]

I don't think that you can use a switch that only breakes one side of the circuit if it has an on and off position.

404.15 B Off Indication. Where in the off position, a switching device with a marked OFF position shall completely disconnect all ungrounded conductors to the load it controls.

Theres ways around everything, use a three way as a single pole, (no off position) though I think I would go the DP power relay route, and just run it LV.

 

[shaw0486]

use a shunted breaker.

 

[Volta]

I don't think that you can use a switch that only breakes one side of the circuit if it has an on and off position.

404.15 B Off Indication. Where in the off position, a switching device with a marked OFF position shall completely disconnect all ungrounded conductors to the load it controls.

I think your right!

Theres ways around everything, use a three way as a single pole, (no off position) though I think I would go the DP power relay route, and just run it LV.

And you too!

 

[ty]

I would use the contactor method.

 

[hardworkingstiff]

I don't think that you can use a switch that only breakes one side of the circuit if it has an on and off position.

404.15 B Off Indication. Where in the off position, a switching device with a marked OFF position shall completely disconnect all ungrounded conductors to the load it controls.

While I agree and like your logic, I'd feel a lot better if this was not under the "Construction Specifications" section and was instead in the "Switch Connections" section (404.2).

 

[mivey]

If you wanted to go that far, you could then mount a small 240v-24v transformer and run bell/thermostat wire to a switch.

I'll see your bell wire and raise you an X-10

 

[mivey]

See 404.14 (b) I would say the switch is going to see 240 volts. Plus if it switches under load it will see a voltage that is somewhat higher. I can not give you eng. data to support this. Maybe some of the engineers can.

No current = no voltage drop in the element = all of the 240 volts is across the switch.