Any benefit to having a main power switch and a separate power switch for the PID?

[BBBF]

Does the PID need it's own on/off switch?

I think I know the answer to this, but I'd rather ask than be sorry. Is there any benefit to having a main power switch and a separate power switch for the PID or is that redundant? In my original design, I didn't have a main switch, but I had a switchs to turn on the PIDs. I've decided to add a key switch further up the circuit to prevent any damage from someone that can't resist pushing buttons. I assume I can just use this switch to power the PIDS and eliminate the switches down stream. There will still be a switch between the PID and the SSR.

 

[Setesh]

I can't think of one. Can you think of a situation where you would need your PID to be off while the rest of the panel is turned on? I've done about 20 brews with my panel and haven't run into a situation like that yet.

 

[LandoLincoln]

Well, let me think...

IF you had a main power switch and no on/off switches for the PIDS...and IF you did NOT install any on/off switches and contactors for the heating elements...and you did NOT install any float switches in the HLT or BK...and you powered up the system, the PIDs could kick on and likely send power signals to the SSRs which would send power to the heating elements, and you probably wouldn't want that. The HLT's job is done halfway through the brew day, so you need to shut that one down while the BK is still going.

So if you DID install on/off switches and contactors for the heating elements, or if you DID install float switches in the pots to interrupt power when there's no water in the pots...then yeah, on/off switches for the PIDs are redundant. But they do add some more bling to the control panel, and impressing your brew buddies IS important.

 

[iijakii]

In my first build I had a power switch & PID switch. In my new one I'll have neither, just element/pump switches. I never ever had the PIDs off. Not using a power switch this time because I don't leave it plugged in due to it not being a permanent basement setup or what have you.

 

[BBBF]

Well, let me think...

IF you had a main power switch and no on/off switches for the PIDS...and IF you did NOT install any on/off switches and contactors for the heating elements...and you did NOT install any float switches in the HLT or BK...and you powered up the system, the PIDs could kick on and likely send power signals to the SSRs which would send power to the heating elements, and you probably wouldn't want that. The HLT's job is done halfway through the brew day, so you need to shut that one down while the BK is still going.

So if you DID install on/off switches and contactors for the heating elements, or if you DID install float switches in the pots to interrupt power when there's no water in the pots...then yeah, on/off switches for the PIDs are redundant. But they do add some more bling to the control panel, and impressing your brew buddies IS important.

My system is dual 120V and I orginally planned on a smaller enclosure. In my new, larger enclosure, I want to use a contactor to close the two hot wires. I couldn't fit a contactor in the smaller enclosure (using mini-relays), so I couldn't get around needing two switches and it seemed more logical to have an on switch for each PID than two main switches.

I was pretty sure I knew what I was doing, but thanks to everyone for confirming it.

 

[kal]

Does the PID need it's own on/off switch?

As others have said: Nope.

Kal

 

[processhead]

No need in majority of control applications.

 

[stevehaun]

I occasionally get an error code on my pid. I clear them by turning my PID off and then on again. I would rather flip a switch than power off my 50 amp system. Other than that, I agree it is not necessary.

 

[celtic_dude]

At first i was going to have a power to my PID but decided to just have a main power switch.