Planning Control Panel Build

[Herb3]

I am slowly getting everything together to convert over to electric from propane for my BIAB set-up. My plan is to build a simple panel using parts form Auber Instruments. My panel will have the following:

• Box for 1/16 DIN controller 8x5.5x9
• SYL-2352 PID
• (2) 40A 120V coil contactors
• 40A SSR
• External heat sink for 40A SSR
• (3) Selectors switches (On-Off for Main Power, Alarm and Element)
• (1) Push button illuminated switch for pump
• 120V Flashing alarm buzzer
• 240V Amber LED for element

Below is one of PJ's great drawings that I changed a bit to match the panel I plan to build. Anyone see any problems with the reworked drawing or my plan so far?

Thanks!

 

[Brumateur]

Second contactor and its sitch are redundant. One is enough.

 

[Herb3]

Second contactor and its sitch are redundant. One is enough.

The original drawing had an E-Stop and a key switch. I took the E-Stop out and replaced the key switch with just a on/off switch. I like the ideal of having a main switch that kills everything after it if needed.

 

[Brumateur]

OK. undestood. But anyway, "left" contactor is not needed.

 

[Herb3]

OK. undestood. But anyway, "left" contactor is not needed.

Cool. Thanks for the info and taking the time to look this over for me.

 

[doug293cz]

I'd keep the left contactor, ditch the right, and put the switch from the right contactor between line 1 and the coil of the left contactor (after switch 1.) Switch 1 then controls power to everything, and switch 2 controls power to the contactor, element and SSR.

Brew on

 

[jeffmeh]

You can certainly keep both contactors, one for main power and the other for element power (so you know off means off), as per your original intent.

 

[Brumateur]

yes controller with two contactors will work, but both contactors control only an element and nothing else. So you can remove one of them without affecting any functionality.

 

[Herb3]

yes controller with two contactors will work, but both contactors control only an element and nothing else. So you can remove one of them without affecting any functionality.

Yup I see where I screwed up redoing the drawing.

Thanks again.

 

[jeffmeh]

yes controller with two contactors will work, but both contactors control only an element and nothing else. So you can remove one of them without affecting any functionality.

If that is the case, then it makes little sense. I thought the OP was going to have the main power contactor cut the power to the whole box, including the element, PID, pumps, etc., and another contactor to cut power to the element while everything else is still powered. No diagram now, so if I missed it, my apologies.

 

[Brumateur]

by current diagramm both contactors controll only element. Yes it possible to do a such modification. But to controll a pump and a PiD will be enough a10 amp rated switch wich already present on diagramm. So switch 1 controlls all power and second contactor controls elemsnt using switch 2. First conactor is redundant.

 

[Herb3]

If that is the case, then it makes little sense. I thought the OP was going to have the main power contactor cut the power to the whole box, including the element, PID, pumps, etc., and another contactor to cut power to the element while everything else is still powered. No diagram now, so if I missed it, my apologies.

Yes that was my plan. When I redid the original drawing I did not take out one of the "legs" and tie it back to the 1st contactor.

Corrected drawing should be up now.

 

[Herb3]

by current diagramm both contactors controll only element. Yes it possible to do a such modification. But to controll a pump and a PiD will be enough a10 amp rated switch wich already present on diagramm. So switch 1 controlls all power and second contactor controls elemsnt using switch 2. First conactor is redundant.

Yup it is a 10A rated switch so even with the corrected drawing looks like I can get by with only the contactor for the element.

Thanks

 

[Herb3]

Based on the help I received here is my current plan for a control panel.

• Box for 1/16 DIN controller 8x5.5x9
• SYL-2352 PID
• 40A SSR
• External heat sink for 40A SSR
• 40A 120V coil contactor
• (3) Selectors switches (On-Off for Main Power, Alarm and Element)
• (1) Push button illuminated switch for pump
• 120V Flashing alarm buzzer
• 240V Amber LED for element

 

[doug293cz]

Your element light is going to flash in time to the output pulses of the SSR. Is that what you intend? Or, did you want the light on whenever the element power switch is on?

Brew on

 

[Herb3]

Your element light is going to flash in time to the output pulses of the SSR. Is that what you intend? Or, did you want the light on whenever the element power switch is on?

Brew on

My original plan was to have it like its wired now to show when the element is firing but the more I think about it I think it would be better to wire it so it shows the switch for the element is in the on position or replace that switch with a lighted push button like for the pump.

Thanks!

 

[doug293cz]

My original plan was to have it like its wired now to show when the element is firing but the more I think about it I think it would be better to wire it so it shows the switch for the element is in the on position or replace that switch with a lighted push button like for the pump.

Thanks!

Could do both. Now that I think more about it, I like the idea of visual feedback about what the element is up to.

Brew on

 

[drksky]

I'm trying to plan out some sort of simple PID control panel and all I'm getting is a headache.

So, my stupid question of the day is, what's the function of the contactor with the 120v coil? When the switch is open, the coil opens cutting power to the boil element outlet? So is it just in place to definitively have 0 voltage going to the element (since SSRs leak)?

 

[doug293cz]

I'm trying to plan out some sort of simple PID control panel and all I'm getting is a headache.

So, my stupid question of the day is, what's the function of the contactor with the 120v coil? When the switch is open, the coil opens cutting power to the boil element outlet? So is it just in place to definitively have 0 voltage going to the element (since SSRs leak)?

SSR's ususally fail closed (conducting), so without the contactor, you can't cut the voltage/current to the element if the SSR fails (without hitting EPO, unplugging the element, or switching off the breaker.) With the switch and contactor, you know that the element is unpowered when the switch is off, even if the SSR is borked.

Brew on

 

[drksky]

SSR's ususally fail closed (conducting), so without the contactor, you can't cut the voltage/current to the element if the SSR fails (without hitting EPO, unplugging the element, or switching off the breaker.) With the switch and contactor, you know that the element is unpowered when the switch is off, even if the SSR is borked.

Brew on

I guess I was looking for more how a contactor works. Applying voltage to the coil, via the selector switch, pulls the coil down closing the 240 closing the circuit and allowing power to flow to the element. Correct?

 

[jwalkermed]

I guess I was looking for more how a contactor works. Applying voltage to the coil, via the selector switch, pulls the coil down closing the 240 closing the circuit and allowing power to flow to the element. Correct?

Yes

 

[drksky]

Yes

Thanks. I think some of this is finally starting to sink in.

 

[doug293cz]

I guess I was looking for more how a contactor works. Applying voltage to the coil, via the selector switch, pulls the coil down closing the 240 closing the circuit and allowing power to flow to the element. Correct?

Yes, powering the coil causes the switch(es) in the contactor to close. The contactor is just a big relay.

Brew on