Hey, any of you nice people know how to program one of these PID's to remain at a constant temp? I don't know what I have done, but when my water gets to the set value the PID wont cycle on and off to maintain the temp. It just stays on and the water keeps heating :angry-banghead:
Re: REX C100 PID
Posted: Sun Apr 13, 2014 6:16 pm
by punchy21
I haven't used one if those before but it sounds like it maybe a setting issue? Have you changed any of the settings from factory?
Re: REX C100 PID
Posted: Sun Apr 13, 2014 6:21 pm
by Linny
Yep , are you sure the thermo couple has access to your wash ( as in is it too far away ? )
Auto tuning does help with the ramping of the element , but you might want to look at your cycle (R) to 1 sec
EDIT: can you take a photo of the label on the side of the PID ? there are several different models .
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:02 pm
by Kimbo
Yeah mate, the TC is definitely working, as the PID is seeing what the temp is. I will adjust the Settings and report back :handgestures-thumbupleft:
20140413_165428.jpg
20140413_163327.jpg
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:10 pm
by Yummyrum
I hope you are not using it to control the element direct. ......Thinking fused contacts... Hopefully you are using it to control an SSR with it an external power supply.
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:20 pm
by Linny
that PID wont control a SSR , you have to modify it since the output is a relay (like the SSR) and not a 12vdc SSR like it should say
Whats happening is there is a small 3amp RELAY inside , which is turning your external SSR to full on. It does work , i had to do it to mine
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:33 pm
by L'ambeq
Hello Kimbo,
plesase send a wiring diagram or pictures so that it is possible to look if it is an connecting issue....
After that it makes sense to ask for the settings!
The controller should do a very good job if everything is OK , 0,5 degrees close to the setpoint is possible!
We will see if we can realise that!
Best regards
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:37 pm
by Kimbo
Yummyrum wrote:I hope you are not using it to control the element direct. ......Thinking fused contacts... Hopefully you are using it to control an SSR with it an external power supply.
All good there mate :handgestures-thumbupleft:
Linny wrote:Yep , are you sure the thermo couple has access to your wash ( as in is it too far away ? )
Auto tuning does help with the ramping of the element , but you might want to look at your cycle (R) to 1 sec
Nup! still not stopping at temp :crying-blue:
punchy21 wrote:I haven't used one if those before but it sounds like it maybe a setting issue? Have you changed any of the settings from factory?
definatly, I changed heaps of things which I cant remember... but I thought I put it all back to the factory settings
Linny wrote:that PID wont control a SSR , you have to modify it since the output is a relay (like the SSR) and not a 12vdc SSR like it should say
Yep, did that too :handgestures-thumbupleft:
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:53 pm
by Linny
So you have modded and removed the relay in the PID ? .... if so , do you have a schematic or mud map how its all wired up
Re: REX C100 PID
Posted: Sun Apr 13, 2014 7:56 pm
by punchy21
As it is heating up, is it turning on and off? And when it reaches temp it just stays on?
Re: REX C100 PID
Posted: Sun Apr 13, 2014 8:17 pm
by mickiboi
If its getting to temperature and then staying on it sounds like you have the control action set wrong. It should be on 100% until it reaches temperature and then it should start to pulse on and off to maintain temperature. You may have the controller set for cooling, not heating. Change setting SL6 and see if that helps. See this for more help http://www.fmfranklin.com.au/products/d ... 100set.pdf.
Re: REX C100 PID
Posted: Sun Apr 13, 2014 8:25 pm
by punchy21
I was thinking that too but wouldnt PID stay off if the temp is below set point?
Re: REX C100 PID
Posted: Sun Apr 13, 2014 9:11 pm
by mickiboi
punchy21 wrote:I was thinking that too but wouldnt PID stay off if the temp is below set point?
Hey punchy. Direct action means Increase in input = increase in output. Reverse action means increase in input = decrease in output.
If temperature(PV) is below setpoint(SV) and its set to cooling the controller will pulse on and off and as it approaches setpoint it will pulse quicker and quicker. When it passes setpoint it will go on 100% as it has exceeded it cooling setpoint so maximum output is required.
If temperature is below setpoint and its set to heating the controller will be on 100% as maximum output is required and as it passes setpoint it will pulse on and off slower and slower until it maintains setpoint.
Hope this helps
Re: REX C100 PID
Posted: Sun Apr 13, 2014 9:27 pm
by Kimbo
Linny wrote:So you have modded and removed the relay in the PID ? Yes.... if so , do you have a schematic or mud map how its all wired up
PID Wiring.jpg
mickiboi wrote:If its getting to temperature and then staying on it sounds like you have the control action set wrong. It should be on 100% until it reaches temperature and then it should start to pulse on and off to maintain temperature. You may have the controller set for cooling, not heating. Change setting SL6 and see if that helps.
It did this when I was fucking around with the SV.... and its set to heating.
punchy21 wrote:As it is heating up, is it turning on and off? And when it reaches temp it just stays on?
as above ;-)
mickiboi wrote:If temperature is below setpoint and its set to heating the controller will be on 100% as maximum output is required and as it passes setpoint it will pulse on and off slower and slower until it maintains setpoint.
Yes, this is exactly how it should be operating..... but its not :crying-blue: I will go and record where all my settings are and post them ;-) Thanks heaps guys :handgestures-thumbupleft:
Oh!... build pics to follow soon :mrgreen:
Re: REX C100 PID
Posted: Sun Apr 13, 2014 9:44 pm
by Kimbo
OK, my notes thus far: when i turned it on, it didnt cycle or or predict, it just went to full power. When it got to temp, the PV flashes but continues on full power. AL1= 50 AL2= 50 ARU= 0 P= 30 I= 240 d= 60 Ar= 25 r= 1 oH=2 SC= 0