1 PID Switchable for 2 5500W Elements

I'm not sure if this has been covered here or not, have searched and come close but no cigar just yet.

I have a rough version of my system laid out and built...Auber PID, heatsink & 40A SSR...The system consists of an HLT and a BK Keggles with 5500W elements in each (30 Amp @ 240V, thus the one element firing at a time). I was originally going to have one PID controlling one SSR to a single outlet firing one element at a time...this would entail me physically switching the plugs from the HLT to BK or vice versa, depending on which I was using.

Is there a way I could control, via a switch, which element would get power without me having to plug & unplug from a single receptacle? That would be one PID firing an SSR and I assume a switch/contactor(s) setup AFTER the SSR, or maybe some other configuration. This way I may be able to hard wire the elements into the control panel or at least have them plugged in all the time.

Anyone have any ideas if this is feasible or how I can go about doing this? It may have already been outlined here...some of P-J's diagrams that I've found were so close but missing that one switchable component I'm lookin for. If you need any other specifics please let me know...Thanks.

Just use two SSR's and a simple toggle switch to switch the SSR output of the PID between the SSR for each element.

That wouldn't necessarily isolate the elements from getting power though, in the event where something went wrong and there was a failure somewhere I would potentially have loads to both SSR's & elements. I'm thinking along the lines of a 3-way switch to two (2) separate contactors but I can't envision if this would be appropriate or not or even doable.

I do exactly what you are looking for: 1 PID, a simple 3-position switch to select HLT-nothing-BK (I wanted to make sure that it was definately break-before-make). One nifty thing with my setup is that this switch ALSO switches the temp sensor input that goes back to the PID. So, when you use the switch to select the element, you are also selecting which thermocouple is connected to the PID.

Why measure temp in the BK? Good to know while chilling.

I've used this system on about 75 batches now. It does work fine. It can be done with less SSRs, but I like it this way.

I also have a 30A Double pole switch to turn off all the power to both elements just to make damned sure.

Schematic is in the thread. PM me with questions, or just ask them in that thread.

https://www.homebrewtalk.com/f170/240vac-toolbox-control-panel-pics-184296/

I built pretty much what you are looking for last year. 1 PID and 1 SSR controlling 2 elements via a switch. I used two contactors to control which element was receiving the power - the switch triggers the contactors. I only have the temperature sensor in the HLT - when powering the boil kettle I'd use the PID in manual mode, and I have a thermometer built into my boil kettle already so I don't need a sensor for that. I used a P-J diagram, but made a few changes to it -you can check out my build here:

https://www.homebrewtalk.com/f170/my-two-5500-watt-element-1-pid-ssr-build-281085/

Recently I've added in a PWM circuit to control the boil kettle, so I only use the PID for controlling HLT temps now, but the way it was originally built matches your needs pretty well.

I'd recommend making your HLT and BK identical. If one goes down for any reason, you could conceivably still brew with just the other (and a mash tun of course). At least that's my "Plan B".

You guys ROCK! I do want to get away from toggle switches though...my problem is that I don't understand the wiring or function of the blocks. I need to have them in my hand and play to figure them out...

Seriously though...HBT is by far the most valuable resource for anything brewing related...ANYTHING!

illin8 said:

You guys ROCK! I do want to get away from toggle switches though...my problem is that I don't understand the wiring or function of the blocks. I need to have them in my hand and play to figure them out...

Seriously though...HBT is by far the most valuable resource for anything brewing related...ANYTHING!

Click to expand...

The only switch on my panel that uses blocks is the e-stop switch - I'd never used a switch with blocks before either, but when I got the switch it was pretty easy to figure out. You can get them with NO (normally open) or NC (normally closed) blocks, and by adding additional blocks to the switch you are essentially adding poles to the switch (allows you to switch more things on and off with the same switch).
Auberins carries some selector switches now - one of them is an ON-OFF-ON selector that should work in a system like I built in place of the DPDT toggle switch. P-J or someone else could help with specific wiring questions. Toggles do work well too, but they are not as cool looking.

This is this switch..Its number one on diagram..
Theirs another diagram with E-STOP..but cant seem to find it.
I buildt it and it works..


http://www.drillspot.com/products/477422/nkk_s333_maintained_toggle_switch


https://www.homebrewtalk.com/f170/simple-eherms-following-pjs-diagram-w-only-1-pid-221403/

Double-R said:

This is this switch..Its number one on diagram..
Theirs another diagram with E-STOP..but cant seem to find it.

Click to expand...

I like this setup. If I built mine again, I'd probably go with something very similar.

The only drawback is that the thermocouple doesn't get switched. I'd probably still have a switch for that. (although I don't even look at that temp anymore now that I have a dial thermometer on the output of my plate chiller).

And, I'd probably just use a 2-position selector switch, then have a separate SPST switch to kill all the power to the elements. I realize the center position of the selector does that, but it would be too easy to accidentally switch that and kill a dry element.

passedpawn said:

easy to accidentally switch that and kill a dry element.

Click to expand...

I done that.

And here is the one with the E-stop..

Double-R said:

I done that.

And here is the one with the E-stop..

Click to expand...

If you use this diagram, just be sure that the element selector switch that you use is capable of handling the 220v 23 amps that will be flowing through it. I wasn't crazy about 23 amps running thru a switch that I had to handle with wet hands, so I used contactors to control the main load. The switch in my diagram uses 120v and the contactor coils only pull less than 1/4 amp or something like that. Plus I like the cool clunking sound of the contactor that let's me know the element is powered up.
It's your choice though.

bigljd said:

If you use this diagram, just be sure that the element selector switch that you use is capable of handling the 220v 23 amps that will be flowing through it. I wasn't crazy about 23 amps running thru a switch that I had to handle with wet hands, so I used contactors to control the main load. The switch in my diagram uses 120v and the contactor coils only pull less than 1/4 amp or something like that. Plus I like the cool clunking sound of the contactor that let's me know the element is powered up.
It's your choice though.

Click to expand...

In case anyone looks at mine, the little toggle only carries the low voltage pid control signals. I had exactly the same feeling you mentioned, which is why I made it that way.

illin8 said:

That wouldn't necessarily isolate the elements from getting power though, in the event where something went wrong and there was a failure somewhere I would potentially have loads to both SSR's & elements. I'm thinking along the lines of a 3-way switch to two (2) separate contactors but I can't envision if this would be appropriate or not or even doable.

Click to expand...

illin8,

I got your PM and also have been following this thread. I took on your challenge of making a diagram that should fit your desired plan.

As always - Click on the image to see (and save) a full scale diagram that is printable on Tabloid paper (11" x 17")



I sure hope this helps you in your adventure. If you need anything changed on the diagram, Please let me know.

Note: Please do your setup using GFCI protection. You can get an inexpensive Spa Panel from HomeDepot to do that for you. I can also supply the wiring set up for that if you need it.

Wishing you the best.

P-J

Another possibility is for a wiring plan that does not use the contactors.

I know there has been a lot of concern about my selection of the element power switch in previous diagrams. This one uses a completely different switch that is rated for 30A for both 120V and 240V applications.
http://www.digikey.com/product-detail/en/S823%2FU/
The data sheet: http://www.nkkswitches.com/pdf/stoggleshighcap.pdf
The price in not all that bad either @ $23.46

Anyway here is the diagram & as always - Click on the image to see a full scale diagram that is printable on Tabloid paper (11" x 17")



Hope this helps someone in their planning.

P-J

P-J said:

illin8,

I got your PM and also have been following this thread. I took on your challenge of making a diagram that should fit your desired plan.

As always - Click on the image to see (and save) a full scale diagram that is printable on Tabloid paper (11" x 17")



I sure hope this helps you in your adventure. If you need anything changed on the diagram, Please let me know.

Note: Please do your setup using GFCI protection. You can get an inexpensive Spa Panel from HomeDepot to do that for you. I can also supply the wiring set up for that if you need it.

Wishing you the best.

P-J

Click to expand...

This thread is awesome and I'm definitely in the same boat and most likely will be using this in my design. I'm also in favor of using two RTS probes with one PID. Suggestions on how to wire that up in this design?

Also, not being an electrician, how are you going from 240v to 120v without resistors? Are the fuses enough?

Dogzbone said:

This thread is awesome and I'm definitely in the same boat and most likely will be using this in my design. I'm also in favor of using two RTS probes with one PID. Suggestions on how to wire that up in this design?

Click to expand...

??? Why 2 RTD temp probes? There is no need to monitor the temp in the boil kettle. A simmer boil and a raging boil are both at a nominal 212°F. The PID has a manual function that allows you to control the % power being delivered for the boil. (With that function the temp probe just needs to be connected & the temp does not matter.)

It can be done but the cost will jump quite a bit (Plus only one of the probes can be calibrated with the PID).

P-J

Dogzbone said:

Also, not being an electrician, how are you going from 240v to 120v without resistors? Are the fuses enough?

Click to expand...

Power is being delivered (in the diagrams) as 240V including a neutral and a ground conductor. This is a 4 wire system. That being said, there is 120V between either of the 2 - 240V lines and the neutral. The fuses have nothing to do with it.

P-J said:

??? Why 2 RTD temp probes? There is no need to monitor the temp in the boil kettle. A simmer boil and a raging boil are both at a nominal 212°F. The PID has a manual function that allows you to control the % power being delivered for the boil. (With that function the temp probe just needs to be connected & the temp does not matter.)

It can be done but the cost will jump quite a bit (Plus only one of the probes can be calibrated with the PID).

P-J

Click to expand...

Many brewers chill in the BK. If using an immersion chiller, a temp sensor is important.

If using a counterflow chiller (plate chiller, chillzilla, etc), BK temp is not so important - better to monitor the exiting wort from the CFC.

passedpawn said:

P-J said:

??? Why 2 RTD temp probes? There is no need to monitor the temp in the boil kettle. A simmer boil and a raging boil are both at a nominal 212°F. The PID has a manual function that allows you to control the % power being delivered for the boil. (With that function the temp probe just needs to be connected & the temp does not matter.)

It can be done but the cost will jump quite a bit (Plus only one of the probes can be calibrated with the PID).

P-J

Click to expand...

Many brewers chill in the BK. If using an immersion chiller, a temp sensor is important.

If using a counterflow chiller (plate chiller, chillzilla, etc), BK temp is not so important - better to monitor the exiting wort from the CFC.

Click to expand...

Makes sense.

Ok - So with that mission I've drawn a diagram so that a seperate RTD probe can be used when the kettles are switched.
(Hmmm... I think it might require 1 more switch to isolate the heating element in the boil kettle during chilling?)

As always - Click on the image to see a full scale diagram that is printable on Tabloid paper (11" x 17")

P-J said:

Makes sense.

Ok - So with that mission I've drawn a diagram so that a seperate RTD probe can be used when the kettles are switched.
(Hmmm... I think it might require 1 more switch to isolate the heating element in the boil kettle during chilling?)

As always - Click on the image to see a full scale diagram that is printable on Tabloid paper (11" x 17")

Click to expand...

illin8, thanks for starting a really informative thread! P-J, thanks for the help and awesome diagrams! One more question from the electronics noob, what is the LED box to the lower right of the diagram and above the legend? Are they contact points on the back of the LED push switches?

Dogzbone said:

illin8, thanks for starting a really informative thread! P-J, thanks for the help and awesome diagrams! One more question from the electronics noob, what is the LED box to the lower right of the diagram and above the legend? Are they contact points on the back of the LED push switches?

Click to expand...

It is the terminal layout for the SW1 type switch. Here is the SW1_manual.pdf for it. I just included it on the diagram for reference.

Glad this topic took off a little bit. Many thanks to P-J for his quick response and valuable input!

How about a discussion on sources for the fuses/resistors and best practices in assembly (as in connections)?

illin8 said:

Glad this topic took off a little bit. Many thanks to P-J for his quick response and valuable input!

How about a discussion on sources for the fuses/resistors and best practices in assembly (as in connections)?

Click to expand...

Welcome.

The resistors, fuses and fuse holders can be sourced from RadioShack.

For assembly I'd use #10 stranded wire for the 240V wiring and #14 stranded for the 120V wiring. Use colored wiring as that will make your life a lot easier.