which PID

[Mark1964]

can anyone recommend a pid there are that many around and they look different so which one is decent? and that can be wired up with ease

 

[Northern Brewer]

REX C100 would be my choice , just over 10 quid each, easily reprogrammable for different thermocouple types. there are some imitations that work but may have "Engrish" instructions but ultimately work - I got the genuine item from here
Even though it says K type thermocouple on the side it took a 2 minute read of the isntructions and 2 minutes to change it to PT100. PJBiker has experience of similar ones with less detailed instructions.

 

[Mark1964]

thanks for that what is different thermocouples? im a cabbage with electronics

 

[tazuk]

i think most use pt100 :thumb:

 

[Mark1964]

The probes :thumb:

 

[Aleman]

This one is very nice . . . I use it in my HERMS



And this is the one I use in the little brewery (Actually two off HLT and Boiler)



OK Auber Instruments may not be as cheap as those from Hong Kong but they have been in use on the forum for 3 or 4 years so people know about them and how to fettle them. Plus we know what inputs and outputs they use.

Auber PT100 Sensors and Auber SSR Range

 

[Springer]

Can't fault As. choice only the price.
You can get a few Chinese ones as spares and still be in pocket, assuming they last reasonably well.
You pays your money and makes your choice.
S

 

[Vossy1]

I'm a big fan of the Auberins SYL-1512A as shown by Tony (top). I've been using them for around 3 years, they've never let me down and the service/time for delivery for me was only 1 week

 

[tazuk]

have a look at this one you may get a bargin :thumb:
http://www.ebay.co.uk/itm/PID-DIGITAL-T ... 1c22bf14ea

http://www.ebay.co.uk/itm/DIGITAL-PID-T ... 5891b6d881

 

[prolix]

+1 for for auber SYL-1512A i have 2 they are excellent

 

[Mark1964]

So works out around £24 that seems reasonable : :thumb:

 

[Mark1964]

Right so seen the pid we need and the probes so what else is needed in the electronics side of the set up or is That it ??

 

[Northern Brewer]

Solid state relays (SSR) are the third part you need
Probe gets the temp and are connected to the PID -> PID works our how much heat is needed -> PID turns on and off the SSR which turns on and off the heating element (or cooling system if its for an FV etc.)

This is the kit list I used

PID

Probes

SSRs with heatsink

Here's my wiring diagram for the HERMS, the HLT is similar but all in one pot

Here's it working as a prototype, the kettle lead goes through the SSR and is switched on and off by the PID, the probe is in the spout fo the kettle. Got a nice metal box to put it all in now but still building the rest of the brewery.

First the equipment used - except the Tesco kettle, resting on the box it will eventually go into.

here's it installed in the prototype box - I used some scrap 4mm earth cable for the prototype to switch the live on the kettle - wrong colours but only used for 10 minutes to prove it

here's the PID and SSR in the plastic prototype box - not tidy but only used for a quick try out.

Here's the PID input type - the label on the side of the PID says K thermocouple but I've reprogrammed the PID to use PT100, the P and upside down L on the bottom row indicate this, instructions to do this came with the PID.

This shows the PID operating the SSR, the green LED at the top left indicates the PID is switching the SSR.

The following image shows the PID has turned off the SSR before reaching the set temperature knowing the heat in the element will continue to heat the water for a while yet

the target temperature has now been reached - you can see the LED pulsing occasionally showing that the PID is turning the SSR on and off to keep the temp stable - well not in this picture - you would have to be there

Cheers
NB

 

[Darcey]

@Northern Brewer

What did you use to mount the SSR? I have one with a heat sink but I guess you need some insulating washers to mount it to your case/plastic box to avoid potential melt down?

 

[evanvine]

I have one with a heat sink but I guess you need some insulating washers to mount it to your case/plastic box to avoid potential melt down?

If your Heat Sink gets that hot it hasn't got enough air flow round it.
I mount mine outside the box.

 

[Northern Brewer]

Hi Darcy

The metal case I bought came with a wood mounting panel in it, I bought a 2mm aluminium sheet from ebay to replace it. I 'm going to mount the SSRs and other components on the ali plate, this will be 350mm sq. It's quite a big box but if the heat doesn't dissipate and still builds up I bought a small 240v fan (shown in the first picture) that I will mount in the side of the case and draw air in through the bottom of the case where the cable entry is.

Problem with the case is its like an armoured tank and cutting the square holes for the PIDs will be challenging. All the other components such as switches I've made sure have round mounting holes so they are easier to cut.

Cheers
NB

 

[Darcey]

If your Heat Sink gets that hot it hasn't got enough air flow round it.
I mount mine outside the box.

I am yet to use the SSR in anger yet I am making sure I have all the bits so I can actually build the control box with full concentration over a day so not to forget where I am up to / be tempted to cut corners.

Hi Darcy
The metal case I bought came with a wood mounting panel in it, I bought a 2mm aluminium sheet from ebay to replace it. I 'm going to mount the SSRs and other components on the ali plate, this will be 350mm sq. It's quite a big box but if the heat doesn't dissipate and still builds up I bought a small 240v fan (shown in the first picture) that I will mount in the side of the case and draw air in through the bottom of the case where the cable entry is.
Problem with the case is its like an armoured tank and cutting the square holes for the PIDs will be challenging. All the other components such as switches I've made sure have round mounting holes so they are easier to cut.
Cheers
NB

My enclosure has some screw fixing points on the back pannel that allow airflow behind what ever is mounted but I suspect I will buy some washers anyway to keep the base of the heatsink off the plastic. I have looked at the 240V fan option but there isnt enough room in the box I have unless I buy another box and just use this one for HLT/Herms.. which may be a good idea :hmm:.

Could you wire the fan to run while only the SSR is working if so that may be an option. There is enough wurrring as it is in the cellar but if its needed... its needed..

I shall un hijack the thread now.. sorry. :whistle:

 

[Northern Brewer]

Could you wire the fan to run while only the SSR is working if so that may be an option. There is enough wurrring as it is in the cellar but if its needed... its needed..

I guess you could have the fan in parallel with the heating elements, however once the liquor/wort is up to temp then the SSR is only pulsed a little so probably doesn't need cooling that much if it has a heat sink and the fan would only kick in momentarily. A simple switch on the fan may be a good option

Also if you have a solar pump PSU (or just get a cheap 12v adapter) you could use a smaller fan off of a PC which are nearly silent.

 

[Darcey]

I think I need an SSR for my brain. I think i'll start a new thread... :shock:

 

[Vossy1]

You might also want to consider fitting an in-line fuse in the PIDS L supply, it don't take a lot to blow them.