Wiring Diagram Help

Discussion of the physical aspects
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Yorg
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Wiring Diagram Help

Post by Yorg »

Hi, I suppose you've heard it before - "I'm not technical...."
I've done my best to put together a wiring diagram, and I'd really appreciate some help.
It's attached.
Besides a general lookover, specifically I'm not sure how I've wired:
-the temp probe - the negative side
- the negative side of the 'green' ssr and the relays, going back to the BCS
- the GND between temp0 and temp1, what should that physically be wired to?

In case you're wondering, the 'purple relay controlling the AC and DC pumps is to control two pumps at the same time (one AC, one DC) during the same chill process.

And is this a good purchase for the 'blue' relay: ebay item number 280737858546
http://www.ebay.com.au/itm/1-Channel-Re ... 415d47c3f2

And what about this for the 'purple' relay: ebay item number 330766736004.
http://www.ebay.com.au/itm/SRD-05VDC-SL ... 4d033bda84
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Electrical Schematic 2_1263x800.jpg
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clearwaterbrewer
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Re: Wiring Diagram Help

Post by clearwaterbrewer »

I would be careful to get relay boards that are wired correctly (the relay energizes when the input is +5v) there are reverse ones out there.. I bought a 8-channel one and learned the hard way..
I would get a 12V powered relay board, you have linked a 5V powered one... as you have a 12V power supply (you do NOT want to power the relay board with the BCS!)

This one will work fine:
http://www.ebay.com/itm/Two-Relay-Modul ... 3cab83d59e

read the description and see that this one describes how the relay operates (the relays you specify do not):

Input control signal voltage:
0V - 0.5V Low stage (relay is OFF),
0.5V – 2.5V (unknown state).
2.5V - 20V High state (relay is ON).


-mike
Yorg
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Re: Wiring Diagram Help

Post by Yorg »

Thanks for the reply.
So, the relay board is powered separately from the 12 v supply, but the 5V control output from the bcs is used to switch the relay coil?
And what do I do with the negative side of each relay coil - how do I ground them or return them to...?

Can you also help me with the temp probe question?

And as for the SSR, can I connect it directly to the bcs as long as it draws less than 20mA, or should I be switching it through another one of those relays?

Cheers
JonW
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Re: Wiring Diagram Help

Post by JonW »

Yorg - you are correct, the relays will be powered from the 12V, but the 5V will be used to trigger them. They are setup using Darlington transistors to do this - it's kind of like having a mini 5V relay triggering the larger 12V relay. This allows you to use the 5V triggering by using more robust relays. You need to tie the ground from the 12V power supply to the BCS ground.

Yes, the BCS can drive the SSR relays directly. They use very little power draw.

On your temp probes, there is not a polarity to them, so it doesn't matter which lead is attached to the GND port and which is attached to the TEMPx port. However, if you're using ones like those from ECC, I would put black on GND and white on TEMPx. All of the GND connections on the BCS are common, so it doesn't matter which one you use. There are just multiple ones to give you more places for attaching.
Yorg
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Re: Wiring Diagram Help

Post by Yorg »

Thanks John,
I'll try and take it on from there.

Cheers!
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