Switch for element

[Goocher]

I'm in the process of building my E-HERMS system. It's a single element design but I wanted to prepare for a two element design in the future. I'm using a Auber 2352 PID, 40A SSR, Camco 5500W ULWD element, etc. I went to Grainger today to pick up a DPDT switch for my element select (DT to prepare for future). I accidentily bought a switch that is only rated for 20A (Grainger part # 2TPE4). I wanted the 25A one but obviously made a mistake. Is this switch going to be enough or do I need to make the 1 hour hike again?

 

[Goocher]

Bueller?

 

[KitB]

You'd be better off with a 30 Amp Switch.
20 Amps won't cut it...

5500 / 210 = 26.19...

Too much amperage for that switch.
I'd suggest returning it.

 

[passedpawn]

Not enough. You'll be drawing 23A.

HD carries these. I use 2 of them in my system and I can verify they work perfectly.

 

[Monster Mash]

It is better to switch the SSR and not the element. The SSR should be switched with low voltage so you will not need a switch with a high amp rating.

I switch all of mine using the 6v power for the SSR's and then I have a high amp main switch to cut power to the entire unit.

 

[passedpawn]

It is better to switch the SSR and not the element. The SSR should be switched with low voltage so you will not need a switch with a high amp rating.

That switch above is meant to be the high-amp disable for 240VAC.

 

[Goocher]

I understand that the SSR is going to fire the elements. I have a 40a SSR. I want a DPDT selector switch so I can effectively cut all power to the element and when I decided to upgrade to 2 elements, I can decide which element is going to be firing (via a DPDT on-off-on switch)

Question answered though. Looks like I need at least a 25a switch...

 

[Goocher]

.

 

[l3asturd]

If you plan on cutting the coil voltage of DPDT relays then you hardly need any current rating at all. Coil consumption is typically 10VA with AC coils we use. If you use a 240VAC DPDT relay with a 120VAC coil (using 10VA), the coil consumes only 83mA of current.

VA= Voltage * Amperage

Amperage= VA / Voltage

.083333mA = 10VA / 120VAC

 

[ekjohns]

If you plan on cutting the coil voltage of DPDT relays then you hardly need any current rating at all. Coil consumption is typically 10VA with AC coils we use. If you use a 240VAC DPDT relay with a 120VAC coil (using 10VA), the coil consumes only 83mA of current.

VA= Voltage * Amperage

Amperage= VA / Voltage

.083333mA = 10VA / 120VAC

assuming you have a relay. If you want to go simple you can use a higher rated switch without getting a relay correct?

 

[yjfun]

Correct.