Temperature Control Circuit Relay Board

[TriOminos]

Hello everyone. First off apologies if this is not the proper place to post but you will realize my electronic ignorance in a bit.

I have an old chocolate tempering machine that I purchased. It was in really bad shape, destroyed by the floods up in Vermont 4-5 years ago. Anyways the circuit board is junk. I am trying to replace it but the company that made the tempering machine is no longer in business. So here comes my ignorance, where can I buy a new one to get this thing up and running? I'm hoping one of you can steer me in the right direction.

More details: The tempering machine has both a heating unit, that will turn on when temp falls below a level, and it has a blower that will blows the hot air out of the unit if it gets too warm. The control box has a simple on off switch and a simple knob to raise and lower the temp. I have attached a picture of the circuit board in this post (u may click on the picture to make it larger). I have searched the numbers on the board all over the internet but haven't found anything.

 

[barry]

You're probably out of luck, as that board was made by a company that doesn't exist any more. You have several options. That board looks fairly simple. You could try and debug it-there's not much there. You could reverse engineer it: identify the components and trace out the PCB connections and then build a new board (or, get some high school electronic nerd to do it for you). Or, you could purchase some off-the-shelf heater controller (look at omega.com, for starters.) If any of these ideas work, please send me some chocolate. I prefer dark.

 

[milan.rajik]

I can design such a board using microcontroller and write program for it.

 

[FvM]

The board doesn't look too bad and can be probably repaired.

It looks like a basic electronic on/off temperature controller. Depending on the used temperature sensor it can be replaced by a small off-the-shelf industrial temperature controller.

 

[milan.rajik]

A PIC12F683 circuit would be cheaper. These are the components you need

1N4148
a few resistors
2 X Triac to control blower and heater
A PIC12F683
A thermo couple
An op amp

 

[FvM]

A PIC12F683 circuit would be cheaper.

It's cheaper from a present day perspective, but not necessarily better. E.g. less ruggedized.

Designing a new board to replace an existing board or a product available from stock is only "cheaper" if somebody does the design for free.

 

[D.A.(Tony)Stewart]

circuit board is junk

I think your assumption is false.

The board looks fine, with no signs of corrosion and should be a trivial task for any tech or eng. with debug skills to repair.

Start with AC then DC then ST logo IC voltages, then sensor resistance.

This will be the cheapest option.

 

[barry]

I agree with Sunny; it's probably easily repaired. I've seen boards in waaaay worse condition than yours that still work. Not to overstate the obvious, but is there a fuse somewhere...