pid

[KevinR]

Hi
I have gone electric. Do other electric brewers use a PID to control their boil? If so how do you get a rolling boil? Mine keeps turning off and on at boiling point and i dont get a good strong boil.
Advice welcom.
Kev

 

[Fat Bastard]

Set it to 103. That's what I do with mine.

 

[anthonyUK]

There are better controllers for boiler control such as an SCR - http://www.ebay.com.au/itm/4000W-220V-SCR-Voltage-Regulator-Motor-Speed-Controller-Dimming-Thermostat-F5/291391383419

 

[Camo6]

What sort of pid KevinR? Some have a manual mode where you can control the element output as a percentage.

 

[KevinR]

Thanks. The PID is a Sestos.

 

[Adr_0]

Yeah, manual is probably the best option as it gives you full control of the boil. Setting it to 103 might boil off too much. This might be a problem or might not be a problem at all if you have the kettle capacity to cover for it.

Not sure if your PID has it, but some PIDs that have ramp/soak don't have manual mode.

 

[KevinR]

Thanks. Set process to manual &temp at 103c and fine tune with a VA SSR.
Kev

 

[Adr_0]

Thanks. Set process to manual &temp at 103c and fine tune with a VA SSR.
Kev

Do one (set in Auto to 103C) or the other (manual, pick an output 50-80%?), not both. Setting the controller to Manual will disable any set point control which is fine while you are boiling. Staying in Auto with a 103 set point means your controller will increase the output to meet this, but never will be able to so your output will go to 100% (unless you limit it somewhere else in the controller).

 

[TheWiggman]

I just plug my element straight into the wall. The boil certainly rolls.

 

[Camo6]

I just plug my element straight into the wall. The boil certainly rolls.

Tekker hater! ;-)

 

[Adr_0]

I just plug my element straight into the wall. The boil certainly rolls.

What's an "element"? I just use a couple of heavy wires and plug my kettle straight into the wall...

 

[TheWiggman]

To elaborate...
I wouldn't bother controlling the rate of boil, just go 100% on. Either plug the element into the wall or incorporate a bypass in the control box (or set PID to manual 100%). I use a 10 and 15A power plug to my elements so once temp control is done with, I remove and plug into the respective power point.
I was trying to be brief and simple but you went all AHB on me.

 

[steeevo]

There are better controllers for boiler control such as an SCR - http://www.ebay.com.au/itm/4000W-220V-SCR-Voltage-Regulator-Motor-Speed-Controller-Dimming-Thermostat-F5/291391383419

To confirm, is that something which will actually work or are you being sarcastic (damn you internet for your lack of intonation!).

I have just put an element in a kettle which is too big for it (just doing baby brews, but have a 2200W element in a 16L pot - a very vigorous boil). Have been looking into PWMs, PIDs and a whole lot of other TLAs, but this SCR looks like it would be well and truly the easiest thing to us if appropriate. Would I need to get any other bits and bobs for new (new transistors, heat sinks, etc.) or should this just plain work if I wire it in appropriately?

 

[Camo6]

Here's a local option that would do the trick.

 

[dblunn]

The SCR system will work very well but the problem with phase control (which is what this method is) is that it can cause issues for the electricity suppliers when it is applied to large loads. The method is used all the time on things like drills etc. The big question is how big can you go before you get noticed, having aid that you will probably be ok but just be aware of it. It is very easy to implement for a system that uses a simple percentage 'on' time and PID control is fine also, just the time window is 10ms rather than 3-5 sec.

 

[steeevo]

Apologies if I am being a bit thick and thanks for the input so far - the DIY kit from stilldragon does look like an easy option. I guess the question it raises for me is that if I am going to spend c. $60-70 on that anyway ($40 + $15 postage + power line and ends I need), how much more would it cost me to just make a PID?

I've read somewhere (sorry no reference, have read so much on this lately it is all blurring together) that at least some PIDs can just be used as a PWM anyway? Means that in the short term I could just use it as a PWM and if I ever ramp up I can use the additional functionality.

If the price isn't that different I'd probably just got the PID, though get the impression I'm unlikely to find such a convenient kit to bundle it together for me?

Also, has anyone here used the stilldragon kit and instead mounted a power socket into the box itself, instead of having the lead running out? Just wondering if that would be one less thing that could get in the way and break? I was thinking could hook up something like this on the end of the box...

 

[dblunn]

Yes that socket would work. Bear in mind the cost of the SSR, heatsink and box need to be added to the total cost. As for the leads needed for Punkin's (Stilldragon) kit you can get a cheap extension lead and cut it up and use the ends as in/out tails.

 

[steeevo]

yeah, I think that is the advantage of the stilldragon approach, it has the heat sink and everything included. Much lower chance of my managing to electrocute myself. If there aren't equivalent PID kits floating around, I'll just go with that kit and call it a day. Thanks for all the help and sorry for reviving an old thread!