Will this temp controller work?

[krusty2111us]

I'm building a 4 X 4 X 6 oven. Basicaly from the oven plans/info on;
http://www.f-5performance.com/powderoven.htm &
http://www.powdercoatoven.4t.com/

Along with the schematic and electrical parts on the 2nd link will this temp controller work? What additional electrical parts do I or will I need?

controller
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1

[krusty2111us]

Any help...what so ever...

[didde]

You will need a contactor and thermocouple.

[vintagespeedwerks]

now that is a NICE website!!!

[krusty2111us]

OK, I'm going with the aforementioned controller, which includes the thermo couple. My oven is 4X4X4. I have 2 3100w elements. 2 lights, and 1 fan. What kind of contactor do I need? From reading around it sounds like the contactor acts like a relay powered by it's own 110v supply. Is this correct? If so, then do I need a contactor that matches the amps and voltage of my elements? My only electrical experience is DC on aircraft. Help...

[RayDean]

A contactor is no more than a heavy duty relay.
It has a solenoid that opens and closes the contactor points.
the solenoid is an electro mechanical (magnetic) coil that when power is supplied draws the units contacts open and closed.
The contacts on the "relay" (contactor) need to be able to handle the amp draw of the ovens heater units combined.
The solenoid can be any voltage you decide, like 12 or 24 DC or 110 volt or even 220 AC.
The solenoid is independant of the relay (contactor) contacts to the heater units.

The temp controller sends the voltage to the solenoid relay that then sends (allows to pass through) the voltage through the contactor.
The controller does this by having the thermacouple in the oven judge the temperature and open and close a relay inside the temperature controller.
A thermocouple is a simple "sensor" that is heat activated in other words like the coil spring on a carburator choke.

So in a word...
Yes, you need the contactor to be able to handle the amp draw of your heating elements, if you use 2 elements you must figure the draw of both together.

Convert Watts to AMPS:
AMPS = Watts / Voltage
I = P ÷ E
Example:
2,300 WATTS = 2300w divided by 120v = 19.1 AMPS
(for 3 Phase divide by 1.73)

[krusty2111us]

Thanks brother, that's what I had invisioned in my head, I just wanted somebody to confirm it! I ordered that controller.

[bzer1]

My oven is (for now) 14kw and I opted for a mercury contactor because of the extra amps. If you ever intend to upgrade or expand your oven you might want to go with a mercury contactor. The one I have is a 2 pole 100 amp which allows me to add a few more elements if I choose. Now...They are substantially more expensive than a mechanical contactor, but they will outlast the mechanical type and they are much more efficient. Just something to think about.

[krusty2111us]

Thanks for the info. If you don't mind me asking, where did you get yours from and how much was it?

[bzer1]

It's been a couple of years and I don't remember where I got it from, but I did a quick search for "mercury contactors and found a ton of sources. If I remember correctly I paid about $175 for it. I pulled up one website that had it for $185 and would ship same day.