220V 30A Wiring Diagram Help

I'm looking for some assistance with a wiring diagram. I was originally planning on a single vessel BIAB 2 heating elements. I was going to use independent circuits supplying 120V from a 20A GFI breaker via 3 prong plug. However, I have decided to switch gears. I have decided to step up to 240V from a 2 pole 30A GFI breaker via 4 prong dryer plug.

This is the wiring diagram I was originally planning to use.

https://www.homebrewtalk.com/f170/1...gallon-batches-341219/index4.html#post4329584

I like everything about the wiring diagram. I am requesting that it be modified to show:

1) 240V from a 2 pole 30A GFI breaker via 4 prong dryer plug
2) Single PID and SSR that will provide controls for 2 5500W heating elements
3) Illuminated maintained push button switch to select which heating element to control.

You shouldn't run two 5500 watt elemnts at the same time off one pid at the same time if you are only running 30 amps. You'd be overloading the circuit.
How large are the batches you plan on doing? I use a 4500watt element and only run it about 70% to keep a heavy boil, while doing 12 gallon batches. You may not need that much power.

grandequeso said:

You can't run two 5500 watt elemnts at the same time off one pid at the same time if you are only running 30 amps. You'd be overloading the circuit.
How large are the batches you plan on doing? I use a 4500watt element and only run it about 70% to keep a heavy boil, while doing 12 gallon batches. You may not need that much power.

Click to expand...

Fixed that for ya.

Volts * Amps = Watts
So Amps = Watts/Volts

5500/240 = 22.91 amps, and you have 30 Amps available.
Ignoring the fact that you really do need some headroom in your circuit (For instance, if your panel supplies 220 volts instead of 240 volts, you're at 25 amps!), the most you can run off of 30 amps is 7200. And that will more than likely blow your breaker.
I would wager a single 5500 watt element with PID control (Or PWM) will be plenty, and still leave you with 4 amps or so for ancillary gear.

You CAN use a single PID to control 2 sets of SSR's with a simple switch, but is that necessary in a single vessel system? Many here use a single 5500 watt element in 15+ gallon setups.

If it is single vessel why not stick with one element? Dont start with a diagram and make it fit. Start with requirements. What exactly do you want to do?

Perhaps OP was thinking of (2) 2200 watt elements for power in a single vessel?

I'd say just use one 5500 unless it's 15 gallons or more.

Sorry now that I read through the first post it doesn't make sense. I'm basically interested in a 2 vessel system with 1 240v 5500w element in each vessel. I want to be able to switch because the 2 element so that it is not possible for them to run at the same time. My power is 240v 30a gfci protected. I will be brewing 10 gal batches.

rack04 said:

Sorry now that I read through the first post it doesn't make sense. I'm basically interested in a 2 vessel system with 1 240v 5600w element in each vessel. I want to be able to switch because the 2 element so that it is not possible for them to run at the same time. My power is 240v 30a gfci protected. I will be brewing 10 gal batches.

Click to expand...

Makes a lot more sense now

There are 2 versions of the "PJ 2 element diagram" running around. One that will let you run both elements at the same time, and one that has a switch between the PID and the SSR's to only hook the PID to one element at a time.

You want the one with the switch. The element will pull about 23 Amps, leaving you with 4 or 5 amps to run pumps, controllers, etc.

sounds like a double pole double throw contactor might be in you future.

grandequeso said:

sounds like a double pole double throw contactor might be in you future.

Click to expand...

If you use dedicated SSR's on the contactors, all you have to do is switch the low voltage trigger from the PID/PWM to run 2 elements.

You can switch the high voltage side, but it's more expensive hardware. Switch the low voltage side and you can do it with a $1.00 switch if you want to.

you could certainly do it at the previous post says, with a low voltage switch, many prefer to do it on the load side with a two pole contactor for the sake of safety. If you just cut off the low votage side you would have 120 running thru your element and with the possibility of bleed thru on your ssr it could end completing the circuit and being on when it shouldnt be. A well thought out designs cuts both lines (240v) when you turn the element off.

grandequeso

Thanks for all the help. I found this diagram:



There are only a few things I would like to change:

1) I only have 1 pump
2) I would like a buzzer and alarm disable switch
3) I would like a yellow LED showing that the heating element is powered
4) I would like to have an e-stop

grandequeso said:

you could certainly do it at the previous post says, with a low voltage switch, many prefer to do it on the load side with a two pole contactor for the sake of safety. If you just cut off the low votage side you would have 120 running thru your element and with the possibility of bleed thru on your ssr it could end completing the circuit and being on when it shouldnt be. A well thought out designs cuts both lines (240v) when you turn the element off.

grandequeso

Click to expand...

You're not wrong, but this is what we just went through...

I have always recommended using 2 relays per element to switch both legs of the 240 volt circuit. But don't say you have 120 running through the element when the other leg is cut off.

With one leg disconnected by the relay, there's nothing running through the element. There is the potential of 120 volts if you short the still connected leg to ground, but until that connection is made, no current is flowing.

I know it's academic, but it's confusing to some when people mention 120 in a strictly 240 volt circuit. It's important not to confuse folks checking this thread out a year from now with 120 vs 240. I've seem so many folks think 240 is just (2) 120's, and that's just not the case.

Yes, you can buy 2 contactors as the diagram shows. Personally, I'd buy 4 SSR's and switch the low voltage side. Both methods are safe and effective.

that diagram looks good to me, two spdt relays are probably less expensive than one dpdt relay, and will open and close both poles to either elements. I'll have to respectfully disagree with you sweetstuffs. a ssr doesnt positively open or close a circuit like a contactor does when you remove the control circuit from it. often these ssr's bleed through when they are not powered. That is one reason why it is important to cut out both legs when not in use. Here is unlikely but possible senario, you're cleaning out your HLT while your boil is going, you bump the element and crack it while giving it a good scub, next thing you know you are getting the yoga buddah alla shocked out of you.
This is the type of thing you want to prevent.

rack04 said:

Thanks for all the help. I found this diagram:

There are only a few things I would like to change:

1) I only have 1 pump
2) I would like a buzzer and alarm disable switch
3) I would like a yellow LED showing that the heating element is powered
4) I would like to have an e-stop

Click to expand...

rack04.

I hope this fits your needs:

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



P-J

Great work P-J. Thanks a lot!

I'm putting together a parts list and I'm having trouble finding the 4 Wire 30A 250V plug that will work with the 4 wire dryer receptacle. I can only find them on the ends of dryer cords and not individual.

rack04 said:

Great work P-J. Thanks a lot!

I'm putting together a parts list and I'm having trouble finding the 4 Wire 30A 250V plug that will work with the 4 wire dryer receptacle. I can only find them on the ends of dryer cords and not individual.

Click to expand...

Try this:
amazon.com Leviton 4 wire dryer Plug

By the way, Refresh the diagram. I changed it a little bit to eliminate some fuses.

Hope this helps.

P-J

P-J said:

Try this:
amazon.com Leviton 4 wire dryer receptacle

By the way, Refresh the diagram. I changed it a little bit to eliminate some fuses.

Hope this helps.

P-J

Click to expand...

What rating do the fuses and fuse holders need to have? The fuse holder that I am looking at has solder connections "rated up to 15A at 120V AC".

rack04 said:

What rating do the fuses and fuse holders need to have? The fuse holder that I am looking at has solder connections "rated up to 15A at 120V AC".

Click to expand...

That will be A-Ok. No problem.

I just realized that I messed up on the info label for the link in post #16.
I fixed it to show "Plug" instead.

Are the resistors just soldered inline with the wire going to the e stop or is there a holder?

rack04 said:

Are the resistors just soldered inline with the wire going to the e stop or is there a holder?

Click to expand...

Just solder them in series with regular wire attached at each end. Then, use a piece of shrink tube to cover them to insulate them.

P-J said:

rack04.

I hope this fits your needs:

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



P-J

Click to expand...

P-J,

What size enclosure would I need to fit all these components?

These plans look perfect to what I need! Thanks guys for all of the info! Are there any updates to this build?