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JLD612 & PT100 ??

Posted: Sat Apr 02, 2016 7:39 am
by tupton
The problem I’m having is with the psb offset which is -79°
I checked the offset with a Omega digital thermometer.
The PT100 read 101.2 ohms @ .2c and 134.1 ohms @ 100c
I removed the PT100 from the oven and inserted the tip in boiling water, the JLD612 showed 204 ° while my Omega showed 210.6° ???


Inty = P100
Outy = 2
Hy = 003
Psb = -79
Rd = 0
Corf = 1

Run AT and this is what I have
{NOTE I changed the Souf .02 to .05 as it was over shooting the sv set at 400°}

0036
P = 5.2
I = 0156
d = 039
Souf = .02
Oe = 002
File =0

Thanks

Re: JLD612 & PT100 ??

Posted: Sat Apr 02, 2016 8:01 am
by tupton
I changed out the PT100 for a J type thermocouple reset intf for the J and run the AT and this is what I have

Inty = J
Outy = 2
Hy = 2
Psb = -030 {to correct the temp.}
Rd = 0
Corf = 1

0036
P = 010
I = 0255
D = 063
Souf = .2
Oe = 002
File = 0

Seems like too much correction is needed to get the JLD612 to read the actual temperature ??

Thanks Tom

Re: JLD612 & PT100 ??

Posted: Sat Apr 02, 2016 8:05 am
by tupton
I forgot to mention that I use the controller set up on a oven heating element.

Thanks Tom

Re: JLD612 & PT100 ??

Posted: Sat Apr 02, 2016 5:28 pm
by laserdude
Psb = -79


How did you arrive at this value? I calculate -4.

During auto tune you should expect at least one overshoot. And, changing SouF by such a small amount will make almost no difference.

Re: JLD612 & PT100 ??

Posted: Sun Apr 03, 2016 5:50 am
by tupton
I did a little reading about PID’s and error offset, so now I understand a little better and will try again.

Thanks Tom