Temp controller

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The only hesitation I would have in purchasing this temp controller is the "relay contact capacity rating" It shows it rated for 10 amps at 250 volts. I am not sure that is enough for the start-up amperage for a refrigerator compressor.

I would also want to know what the rating would be for the 110 volt model.
 
The relay rating is good, those are actually the contact ratings. up to 10A and up to 240V, plenty for a fridge.

Worth trying.
 
These look great. I hate to buy from Hong Kong though... that's the only thing.

Please let us know how this goes. Thanks.

I bet Hong Kong has it manufactured in China like Taiwan has to save on their labor costs.
Think about it, how bad it is that even Taiwan has to use Chinese labor?
We laughted at transistor radios back in the early 60's, "hey look Made in Japan".
 
The relay rating is good, those are actually the contact ratings. up to 10A and up to 240V, plenty for a fridge.

Worth trying.

The "fine print" at the bottom of the listing states that a 110V model will be shipped if you live in the US.

I am not sure I am correct about this, I need a real electrician to chime in here, but I think the Amperage rating will go down with the Voltage rating. I know that would be true for wiring but I don't know if the same would apply to these relays.

I HOPE these work - I would like to get one if they do.
 
The "fine print" at the bottom of the listing states that a 110V model will be shipped if you live in the US.

I am not sure I am correct about this, I need a real electrician to chime in here, but I think the Amperage rating will go down with the Voltage rating. I know that would be true for wiring but I don't know if the same would apply to these relays.

I HOPE these work - I would like to get one if they do.

Naw, I am sure the relays are the same regardless of country.
 
The "fine print" at the bottom of the listing states that a 110V model will be shipped if you live in the US.

I am not sure I am correct about this, I need a real electrician to chime in here, but I think the Amperage rating will go down with the Voltage rating. I know that would be true for wiring but I don't know if the same would apply to these relays.

I HOPE these work - I would like to get one if they do.

Third post in.
https://www.homebrewtalk.com/f51/temp-controller-161493/#post1865497
 
Hong Kong is in China.

I wasn't clear. I don't like to buy auctions from anywhere overseas. I feel the same about buying from London as I do from Hong Kong.

I was over there in 88 as well 96 but wanted to be there in late 97 when it was given back to China to see if there was a difference after the takeover.
Rats, (oops thats part of the food chain) I missed that time frame to go back over again.
London also was a big mix of people from around the world and this was back in 87 or 88 during the "storm of the century". Even back then many items were made from theeast sold in their stores. If it weren't for cars and bikes made in Japan English people would be walking.
 
The "fine print" at the bottom of the listing states that a 110V model will be shipped if you live in the US.

I am not sure I am correct about this, I need a real electrician to chime in here, but I think the Amperage rating will go down with the Voltage rating. I know that would be true for wiring but I don't know if the same would apply to these relays.

I HOPE these work - I would like to get one if they do.

Amperage rating should go down with voltage. Anything that pulls 10amps at 240V will pull 20 amps at 120V and vice versa, if something is rated 10 amps at 240V, it should be rated 5 amps at 120V. At 12V it would fall to .5 amps.
 
Amperage rating should go down with voltage. Anything that pulls 10amps at 240V will pull 20 amps at 120V and vice versa, if something is rated 10 amps at 240V, it should be rated 5 amps at 120V. At 12V it would fall to .5 amps.

Not quite....

For inductive loads, yeah. If you have a 240V n HP motor that is the max rating for that relay then an equal HP motor on 240V will draw more current when under load. The big thing is when the relay engages the contacts may wet from the arc and weld itself closed.
The compressor on a fridge isn't close to that kind of load so it isn't a worry.

As for resistive loads the current rating stays the same regardless of the voltage up to the max voltage rating. A resistive load on 240V will draw more current than the same load on 110.

Is my face turning blue? It's good for 240V up to 10A. It's fine.
 
Amperage rating should go down with voltage. Anything that pulls 10amps at 240V will pull 20 amps at 120V and vice versa, if something is rated 10 amps at 240V, it should be rated 5 amps at 120V. At 12V it would fall to .5 amps.

But what about the formula that is used to determine amps?

watts/volts = amps

I have used this a lot to determine the gauge of wiring for a circuit when I built my house and the new shop last year. I am NOT an electrician so I certainly defer to someone with a license. However using that formula I can give the following examples:

1200W/120V = 10A

1200W/240V = 5A

This is why I said that the amperage drops when the voltage increases. I know that is how you figure out what gauge wiring to run for circuits. I would guess this would be true for any conductor.
 
its not a watts/volts thing, its an I²R thing. but that applies for resistive loads, a compressor will draw different amounts of current at different loads. Code rage is probably entirely blue by now...
 
code rage so you think the cheaper would be good? or the 1 that is a little more for the 20amp for cooling? i think it was $10 more for that 1.


i have ordered plenty of stuff from hong kong you just need to be calm as it will take a week to 2 to get here.
 
If they make a 20 amp version for 10 bucks more then I would get it.

I run my keezer on a PID with a 3A contact, shh dont tell any one ;) It all depends on the quality of the internal relay. For 10 extra bucks I would go for the bigger one.

Midnigh7- yes it could but you will need a DC power supply to turn the SSR off and on with. That is if the SSR has a DC coil.
 
If they make a 20 amp version for 10 bucks more then I would get it.

I run my keezer on a PID with a 3A contact, shh dont tell any one ;) It all depends on the quality of the internal relay. For 10 extra bucks I would go for the bigger one.

Midnigh7- yes it could but you will need a DC power supply to turn the SSR off and on with. That is if the SSR has a DC coil.

Hey Code, I wonder what a Fluke meter would read on MAX & MIN amp recorded readings on the keezer compressor starting up vs running amperage? I bet it's way above that 3 amp rated contact in your PID unit. I bet it's screaming ouch inside but holding on.
 
A "El Cheapo" Radio Crap relay controlled by the PID contacts would be a lot cheaper to replace than a PID unit besides the higher amperage capacity of the relay contacts. I went tru a hot tub stat that was having pitting and sticking contact problems causing temps all over the place. After spending $85 for a net stat I wired it to a relay and let the relay take a hammering. With this addition the stat would maintain within 0.10*F for years without welded and pitted stat contacts.
 
I'm sold, mine is on it's way.

I've ordered half a dozen times overseas via ebay the past few years, never a problem. My PayPal account is tied to my credit card so no merchandise within 60 days I dispute the charge, funds go back to my account and someone other than me eats the $30.
 
Hey Code, I wonder what a Fluke meter would read on MAX & MIN amp recorded readings on the keezer compressor starting up vs running amperage? I bet it's way above that 3 amp rated contact in your PID unit. I bet it's screaming ouch inside but holding on.

Yeah, I keep meaning to grab a control relay to put between the PID and the compressor. The relay in the unit isn't getting hot, or ready to burn up but I know when it opens and that large field from compressor collapses it isn't good on those poor contacts. It just may weld them shut one of these days if left this way.
 
OK, I see what your saying. My knowledge in this area is limited to wiring buildings not circuits.

Someone needs to buy one of these things and report on how it works.
 
No, it's not a PID for one and it doesn't have a SSR output. You could just hook up a element straight to it, but you would just have on/off control.

Doesn't need to be. Take a +12VDC power supply and wire the +12VDC to a contact on the controller, wire the other side of the contact to the SSR coil. Then wire the 0VDC from the power supply to the SSR coil.
 
Doesn't need to be. Take a +12VDC power supply and wire the +12VDC to a contact on the controller, wire the other side of the contact to the SSR coil. Then wire the 0VDC from the power supply to the SSR coil.

Doesn't it need to be current limited? I guess a 300ohm resistor in series would work. The bouncing of the contact closure would worry me though.
 
I went for one of these too. I am currently running my fermenting freezer off a ranco controller for cooling and a 60W light bulb for warming. It kills me when they are both on. I think this controller will be great.
 
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