Wiring assistance - single PID/SSR single kettle setup

[johnodon]

With this wiring isn't the element always on as long as the switch for it is on? Or does the element not work with only 120v?

There are 2 switches...one for the PID and one for the element.

Also I don't understand the purpose of the PID in any of these wiring diagrams. Aren't relays on/off switches? So isn't the PID effectively acting as a thermostat as opposed to a PID controller

That is exactly what it is used for. The PID measures/regulates temp and sends the appropriate instruction to the SSR (an electronic switch) to power the element on and off.

John

 

[BrewinBigD]

the element will work on 120v just figure on more current. divide your watts by voltage =approx amperage.

 

[wedge421]

Wow PJ way to step up to the plate!!

 

[arles]

There are 2 switches...one for the PID and one for the element.

Right. And if the switch for the heating element is on it is always at half power. I just wasn't sure why that is the case as opposed to the PID controlling all the power to the element. Basically the PID can't turn the element off.

That is exactly what it is used for. The PID measures/regulates temp and sends the appropriate instruction to the SSR (an electronic switch) to power the element on and off.

But a PID takes a variable input and creates a variable output. Hooking it up to a relay means you can only turn the power on or off, no where in between. Or at least that is my understanding of what is going on. The PID will definitely work but it seems to me to be acting more as a thermostat not a PID. The only reason I ask is because thermostats are cheaper and simpler.

My understanding of this wiring (which definitely could be incorrect) is that the heating element is either at half power or full power. It can be used to control temperature just not as well as it seems like it could.

 

[Lucky_Chicken]

The SSR cuts off one leg of the power with one leg disconnected there is no more current flowing through the heating element.

The percentage delivered by the PID is from a rapid switching on and off of the SSR thats why it cannot be a mechanical relay because they cannot stand that many cycles. In other words if you are set at 70% the PID turns the power on 70% of the time.

Hope that clears it up some.

 

[arles]

The SSR cuts off one leg of the power with one leg disconnected there is no more current flowing through the heating element.

Uh. I still don't understand how this works....

The percentage delivered by the PID is from a rapid switching on and off of the SSR thats why it cannot be a mechanical relay because they cannot stand that many cycles. In other words if you are set at 70% the PID turns the power on 70% of the time.

Ok so it's controlling duty cycle not voltage or current amplitude.

 

[P-J]

Uh. I still don't understand how this works...

Ok. Question for you. If you have a light bulb with only one wire (the hot wire) attached to it, will the bulb light up? I think not as there is no path for the electricity to flow. The same thing applies to a SSR. The SSR is, after all, a "Solid State Relay". When the SSR is not told to conduct electricity, there is no currect path and thus no current flow.

I do not know how else to explain it to you.

 

[BrewinBigD]

I think hes trying to ask if you can run the element at various amounts of current(maybe thinking its how temps are controlled?) The PIDs we use at my shop have a 110vac power supply and a +3vdc output for switching the relay. You set desired temp, the tmp sensor senses current temp and the relay is switched on. Once temp is reached its circut opens and only closes momentarily when needed to maintain or raise temps. Sounds like he thought that you could run it on one leg of the 220 (you could if you went 1 leg and ground) to heat up slower. Poor idea less efficient not as safe in my eyes

Sent from my MB502 using Home Brew Talk

 

[BrewinBigD]

We usually set switchin cycles to 100% (always on) unless the equipment under test requires a certain gain or loss of degrees per minute then well set the cycle accordingly

Sent from my MB502 using Home Brew Talk

 

[johnodon]

I think hes trying to ask if you can run the element at various amounts of current(maybe thinking its how temps are controlled?)

If this is the case, this is easily done by putting the PID in manual mode and setting the Sv to the % of output. I do this for my boils now (thanks to P-J) and set it to 69% rather than 212F.

John

 

[arles]

Ok. Question for you. If you have a light bulb with only one wire (the hot wire) attached to it, will the bulb light up? I think not as there is no path for the electricity to flow. The same thing applies to a SSR. The SSR is, after all, a "Solid State Relay". When the SSR is not told to conduct electricity, there is no currect path and thus no current flow.

I do not know how else to explain it to you.

Ah, sorry I guess I misunderstood how 220 worked. I was under the impression that the two hot lines went through the ground. Thanks for explaining how it works.

 

[KEG99]

I was under the impression that the two hot lines went through the ground. Thanks for explaining how it works.

It took me a long time to figure that one out. Then one day I was looking at the element and noticed only two wires connected to it. Thus one off, no current flow. Doh!

Some of us just need a little bit longer ....

Fortunately, the guys on this forum have patience for us noobs.

 

[BrewinBigD]

If this is the case, this is easily done by putting the PID in manual mode and setting the Sv to the % of output. I do this for my boils now (thanks to P-J) and set it to 69% rather than 212F.

John

is there a reason for exactly 69%? ive heard that for boils its not advised to use auto set for 212F. i dont see why this would be a problem. if your at a boil, and your RTD reads 212F, then shouldnt your heat be controlled to exactly that boil temp? ive heard it can cause a mean boilover doing this in auto mode.

 

[arles]

is there a reason for exactly 69%? ive heard that for boils its not advised to use auto set for 212F. i dont see why this would be a problem. if your at a boil, and your RTD reads 212F, then shouldnt your heat be controlled to exactly that boil temp? ive heard it can cause a mean boilover doing this in auto mode.

The temperature water boils at is affected by altitude as well as what's dissolved in the water. Pure water at sea level boils at 212. Your wort will boil at some other temperature. The problem comes from the fact that once something starts to boil, it stays at that temperature no matter how much energy you put into it. It may boil more vigorously but the temp will stay constant. So the controller can get stuck in a loop where it will continue to add power but can't raise the temperature.

At least that's my understanding

 

[johnodon]

is there a reason for exactly 69%? ive heard that for boils its not advised to use auto set for 212F. i dont see why this would be a problem. if your at a boil, and your RTD reads 212F, then shouldnt your heat be controlled to exactly that boil temp? ive heard it can cause a mean boilover doing this in auto mode.

No real reason other than I achieved a vigorous boil when the PID was in auto mode and set to 212F. I then put the PID in manual mode and started at 77% and worked my way down to 69%. This gave me a nice rolling boil that wasn't too vigorous and very consistent.

John

 

[govain]

Hope this helps.

This looks like a nice simple design similar to what I need. I have a couple questions though.

1) If I don't want the light but want a plugin for a pump, can I replace the light with said plugin but wire it in just before that switch rather than just after it (and ground it of course)? That way the plugin would be always live.

2)I'm not following how the E-stop will work. If I'm following it correctly it just makes it's own loop in the system and hitting the switch off will do nothing but cut the power in that small loop while the rest of the system stays powered. In short, it doesn't look to me like the e-stop is doing anything. If I'm wrong, please enlighten me. I have the misfortune of being cursed with needing to know the "why" and "how" of something before I do it.

Thanks in advance.

 

[Bugaboo]

i'm not to electrically inclined but i think once the e-stop is engaged all of the power would be transfer to ground instead towards any of the equipment. Once current goes to ground it will pull more than the breaker would be rated for and the breaker would break.

The pump outlet in place of light wouldn't work because the dpst switch would break the current so the pump would be only on when the element is on
. Using line 1 would work though. You could forgoe the dpst and wire the pump outlet directly to line 1 and neutral or put a separate switch in for the pump

 

[govain]

i'm not to electrically inclined but i think once the e-stop is engaged all of the power would be transfer to ground instead towards any of the equipment. Once current goes to ground it will pull more than the breaker would be rated for and the breaker would break.

The pump outlet in place of light wouldn't work because the dpst switch would break the current so the pump would be only on when the element is on
. Using line 1 would work though. You could forgoe the dpst and wire the pump outlet directly to line 1 and neutral or put a separate switch in for the pump

I'm still not really seeing how it diverts the power as the hookup for line 1 splits the current rather than being in-line.

And if you read my question again, I said that I'd wire the outlet in 'before' the switch, not after it as the light is.

 

[Bugaboo]

The e-stop once engaged would connect your hot directly to ground which would make a piss load of current run through the hot to ground part of the circuit and trips the breaker. Electricity will go to the path of least resistance which is directly to ground instead of other places in the circuit.

Oh and you're right about the outlet before the switch. I was thinking about how the light worked in that circuit instead of how an outlet would

 

[P-J]

The E-Stop is specifically set up to act in the same manner as the test button on the GFCI breaker. It provides a small leakage current to equipment ground which activates the GFCI and kills all power being delivered to your panel. The 1 amp fuse is there to protect the wiring and the switch. The two 1K ohm resistors are to limit the current flow.

Please keep in mind that you must protect your electric brewery with a GFCI mains breaker. Without it you are playing "You bet your life."!

 

[govain]

Alrighty. Thanks for clearing that up. I didn't realize that it would cause the breaker to trip. That makes more sense now.

 

[cdwiggi]

Hello Gentlemen,

I have been looking at the diagram and wondering about some specifics...
The part where switch one is pictured is that one switch or is it two? If so can you all show me an example of what kind of switch that is or what I need to search for to find that type of switch?

Also after looking over the section of the diagram where the plug is and my own situation I am faced with an issue. I have an older house and can bring a line off at that voltage and amperage but because of the age of the house's breaker box I don't think I will be able to add a GFCI breaker to the mix. I am wondering if it is wise or even possible to add that breaker to this diagram and wire it in?

Thanks

 

[P-J]

This switch from Grainger will work: grainger.com Toggle Switch - 2TPF6

Re: The GFCI breaker - buy this GFCI Spa Panel from Home Depot. Set it up near your brew area. You can wire its input to a dryer or range plug and them mount an outlet in it to supply the power to your brewery.

This way:

Or this way:

Hope this helps you.

P-J

Hello Gentlemen,

I have been looking at the diagram and wondering about some specifics...
The part where switch one is pictured is that one switch or is it two? If so can you all show me an example of what kind of switch that is or what I need to search for to find that type of switch?

Also after looking over the section of the diagram where the plug is and my own situation I am faced with an issue. I have an older house and can bring a line off at that voltage and amperage but because of the age of the house's breaker box I don't think I will be able to add a GFCI breaker to the mix. I am wondering if it is wise or even possible to add that breaker to this diagram and wire it in?

Thanks

 

[jkjod]

Would this set up also work for a 5500W element?

 

[P-J]

Would this set up also work for a 5500W element?

Absolutely.

Please tell up what you are trying to achieve.

P-J

 

[jkjod]

Exactly what Psych was trying to achieve - I am considering converting my boil kettle so I am able to brew indoors and not have to brew at the stove in the kitchen. I am thinking of having a dedicated brew room in the basement so this was a good option.

 

[jkjod]

Actually P-J, this is my plan and if you could draw it p that would great. I would like a key switch to the entire control box, I have nieces and I don't want them accidentally turning something on - so a key would be great so it cannot be turned on without the key. But an indicator light that shows me power is on would be nice as well. From there I will have one 5500W element (with indicator light as element will not always be on), PID, SSR/heat sink, e-stop. I'd like an alarm as well for the PID (I saw them on the Auberin web site). I also like the style of the Auberin push button switches that illuminate to turn on the PID and the element. Thanks for your help

 

[P-J]

Actually P-J, this is my plan and if you could draw it p that would great. I would like a key switch to the entire control box, I have nieces and I don't want them accidentally turning something on - so a key would be great so it cannot be turned on without the key. But an indicator light that shows me power is on would be nice as well. From there I will have one 5500W element (with indicator light as element will not always be on), PID, SSR/heat sink, e-stop. I'd like an alarm as well for the PID (I saw them on the Auberin web site). I also like the style of the Auberin push button switches that illuminate to turn on the PID and the element. Thanks for your help

How about this?

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

 

[jkjod]

That is great, thanks so much this is a tremendous help. One question...Will the LED light on the element Auber switch continuously be on if it has power? I'm thinking that it would be nice to show when there is power to the element and when it is actually in use, for safety reasons.

 

[iijakii]

PJ,

Which in-line fuse holders do you recommend? I'm having a hard time finding some.