STC-1000 wiring - check my work

[Crusty]

This is very easy to follow.

 

[Crusty]

Regarding the compressor delay ( F3 ) does the compressor delay activate every time the differential ( F2 ) is reached or not?
When I wired mine up & testing it out, I set desired temp to 18.0deg, differential to 0.5deg & compressor delay to 3mins.
Everything works perfect, 18.5 & the fridge comes on, 18.0 it turns off & 17.5 the heating switches on. I held my hand over the temp probe & when it hit 18.5, delay light flashes for 3mins & on comes the fridge, perfect. Now that I have it in use & a fermenter bubbling away, I noticed that the compressor delay doesn't activate any more. Is this due to the fridge holding temps for long periods & the compressor delay is not required due to it exceeding the 3mins or should it still activate even though the fridge is off for an hour or more.
When testing, I see that the delay activated only if the temperature fluctuated between heating, off & cooling in the 3min time frame from when the fridge actually turned off.

 

[glaab]

it won't delay if it's been off for more than 3mins already. thats normal

 

[chewy]

Lol I love ATC threads...

 

[Crusty]

it won't delay if it's been off for more than 3mins already. thats normal

Thanks glaab.
I assumed that was the case as it had obviously exceeded the 3min delay that was set.
Working as it should then.
Cheers.

 

[chewy]

You should leave it at 10min delay... The idea is to let the fridge rest between startups and not fk the compressor....

 

[Crusty]

You should leave it at 10min delay... The idea is to let the fridge rest between startups and not fk the compressor....

Well here at the moment, even at 3min delay, the fridge is staying off for an hour or more so I think the compressor will be fine.
If I had it at a tighter differential & warmer ambient temps, I'd probably look at setting the delay higher.
Thanks for the tip though.

 

[chewy]

0,o

 

[ploto]

I can't work out how to repost an image but here's how to do it neatly.

http://aussiehomebrewer.com/topic/70395-help-with-stc-1000-controller-wiring-help/?p=996586

Using the wrong coloured wire even when 'it doesn't matter' is never a smart idea. You never know who might end up playing with it one day. Even what seems obvious to you now may well leave you scratching your head years from now. And no I am not an electrician nor am I affiliated with any.

Perhaps there should be an 'official' STC-1000 sticky thread with a collection of diagrams and photos deemed correct by the AHB hive mind.

 

[godzillalad]

I've jiust wired one of these up too and was wondering why in the instructions does it say

Both heater and cooler must have external AC power

and elsewhere it says to

Safely distinguish the sensor down-leas, power wire and output relay interface

Is there a problem with using the cross wiring like above? Should we be using relays and separate power supplies for heater/cooler?

 

[Yob]

The unit only has one power input so I should think not, essentially it's a switch so no need to make it overly complicated.

 

[booargy]

"Both heater and cooler must have external AC power"

The heat and cool interface are just switches. the unit activates the switch to supply power to the appliance.

"Safely distinguish the sensor down-leas, power wire and output relay interface"

This just means make sure you get the right hole or might be in the pooh. If you run 240V through the sensor the smoke will leak out and it will not work.

 

[QldKev]

I've jiust wired one of these up too and was wondering why in the instructions does it say


and elsewhere it says to


Is there a problem with using the cross wiring like above? Should we be using relays and separate power supplies for heater/cooler?

Is there a problem with using the cross wiring like above
No, pins 1 and 2 are power supply to the stc. The remaining active wires are only getting switched via an internal relay.

Should we be using relays
No need if the load is <=10amp, the device has 2 x 10amp relays built in. If you wanted this to switch a load greater than 10amp then this unit could switch an external relay of greater capacity and the wiring would change to reflect this.


separate power supplies for heater/cooler
No, the device will not run both at one time. So as long as the load does not exceed the source capacity. Ie The device can only switch 10amp. The device itself uses very little power, but should be taken into the entire load.