STC-1000 + 2000w element = Bad idea???

[geologyguy]

So this weekend I used a DIY electric heating system for my HLT for the first time. I used a STC-1000 controller with 2- 2000W , 120 v hot water heating elements. When I had the 2 element plugged in the controller the display dimmed a little and kind of flickered. It also would say 888 or BBB. Also the 20’ extension cord was warm. Found out later the on the bottom of the SCT-1000 there was a bubble and smelt buried. I am pretty sure I fried it. I am confused on I fried. The controller I have been using for a year or so now for my fermenter. The STC-100 is a 110 v and was using 2- 2000w 120v elements. Also I did not ground the elements? Any thoughts?

Heating Elements- Camco 02202/02203 2000W 120V Screw-In Water Heater Element - High Watt Density

STC-1000
Technical Parameters:
1. Temperature measuring range: -50°~99°C;
2. Resolution: 0.1°C;
3. Accuracy: ±1°C (-50~70°C);
4. Sensor error delay: 1 minute
5. Power supply: 110VAC±10%, 50/60Hz;
6. Power consumption: less than 3W;
7. Sensor: NTC sensor (1PC);
8. Relay contact capacity: Cool 10A/250VAC;Heat 10A/250VAC;
9. Ambient temperature: 0~60°C;
10. Storage temperature: -30~75°C;
11. Relative humidity: 20%~85% (No condensate).

 

[stpug]

A 2000w 120v heating element will draw up to ~16 amps, each. An STC-1000 is rated for 10 amp usage, but has components rated up to 15 amps. You put two 2000w elements on one STC-1000, ungrounded. You're lucky that the damage you did is all that happened. It could have been much worse.

 

[Misplaced_Canuck]

Carnac the Magnificent says: I see one of THESE in your future.

MC

 

[thekraken]

Any thoughts?

You were running 33 amps, if your wiring and components aren't rated for that then you could have had a very bad day... Seriously. Underguaged wire => heat build up in wires => insulation melting off wires => shorts, arcing => fire = bad day. (Don't forget about the wiring inside your walls)

Also, your equipment needs to be properly grounded.

[Edit] Your post here makes me a little worried for your safety.

 

[geologyguy]

You were running 33 amps, if your wiring and components aren't rated for that then you could have had a very bad day... Seriously. Underguaged wire => heat build up in wires => insulation melting off wires => shorts, arcing => fire = bad day. (Don't forget about the wiring inside your walls)

Also, your equipment needs to be properly grounded.

[Edit] Your post here makes me a little worried for your safety.

No one was hurt. No wires melted the only thing that happen was inside the actually stc-1000. I used 14 gauge wire. I plan on ground the elements. But do you think they are to much for the controller?

 

[thekraken]

No one was hurt. No wires melted the only thing that happen was inside the actually stc-1000. I used 14 gauge wire. I plan on ground the elements. But do you think they are to much for the controller?

stpug said that the controller is only rated for 10 amps, so they are too much for it. You would need to have the control switch relays like the one Misplaced_Canuck linked to. Make sure all your components are rated for what your doing. That 14 gauge extension cord is too small, your first clue was it was warm to the touch. http://www.engineeringtoolbox.com/wire-gauges-d_419.html

Also, you were running both of these off the same 120v circuit? Is that circuit breaker/fuse and house wiring rated for 40 amps?

Finally, you don't ground the elements them selves, you want to ground any metal equipment that could become live and electrocute you when you touch it.

 

[Tegra]

Wow!

Wondering how you connected this? Must have been a 30 amp circuit?

You can get away with 20amp in 14ga wire if you are careful but 30 will give you a show!

If you were to put the identical elements is series and connect to a 220v circuit you may get away with this. (Although many on the board will still call you down)

Tom

 

[jeffmeh]

Cease and desist until you garner enough electrical knowledge to build a safe solution. Seriously.

 

[augiedoggy]

since it hasnt been spelled out....
1 2000w element needs a 20a circuit (this has the special plug with the single horizonatal plug blade. on the opposite side as the 240v version) If you use a regular 15amp household outlet you are likely going to have breakers tripping after a few minutes otherwise your wiring would heat up and possibly start your house on fire.... It happens (It happened to the house across the street from me because someone didnt pay attention to the fact that an air conditioner draws more power than a lamp cord extension cord can provide. sure it worked for a while and then the house went up in flames)

STC 1000 units have a 10 amp max continuous load capability... when it comes to things like a fridge that might draw 15 amps for a second while starting up will also be ok because they draw less after the second (not the case with a heating element)

1500w elements are the largest that you can safely run on a 15a circuit.

 

[tektonjp]

Well, not to hijack this thread, but in the same vein, what do you electrician guys think of this scenario? I have a 4400w element running on 200v (japan). I'm planning on switching the element to 100v for maintaining temps during a recirculating mash (BIAB) and using an STC-1000 as the controller. At 764w I should be okay, don't you think?

 

[augiedoggy]

Well, not to hijack this thread, but in the same vein, what do you electrician guys think of this scenario? I have a 4400w element running on 200v (japan). I'm planning on switching the element to 100v for maintaining temps during a recirculating mash (BIAB) and using an STC-1000 as the controller. At 764w I should be okay, don't you think?

Yeah but why use an stc for element control? there are many better options like rex c100 or mypin pids for virtually the same money?
stc's have to be modified to properly and reliably drive a heating element... they use mechanical relays )vs an SSR) which switch on and off much slower and wont last long trying to maintain element temps... They are a poor choice.

 

[geologyguy]

Thank you all for the help. I am going to re do the controller. Have a great Weekend