cheese1566
01-13-2013, 11:19 AM
I just acquired an RCBS ProMelt and was wanting to use my PID control box on it. Wondering if the thermostat on the ProMelt might give me issues??
The ProMelt was turned all the way up on the dial past 850. I made a probe mount to keep the tip about 1" off the bottom and near to the spout. The pot was half full of lead and ran for quite a while and nothing was poured from it. The set point was at 700 and at times the temp would go over 800 (before tuning).
I noticed my PID was swinging very high and low, like a digital RPM gauge at times - temp readings that varied 150-200 degrees within 10 seconds. Seemed to do it if touched the top of the probe and "jiggled" it. Wouldn't do it if I stirred the lead.
I got the temp to settle around 700 so I went through the tuning process a couple times. It seemed to stabilize and the readout swings seemed to have disappeared,, even with the jiggle test.
My only thing now is that it doesn't get to 700...stays around 680-690 on the reading.
My PID worked just fine on my Lee 20 pot. I never noticed these rapid swings on the readout and it held the temp pretty much right on. I did change the K thermocouple from a high temp to another high temp with a 6"SST probe from Frozone. I double checked from him about polarity. No other wiring or settings were changed. PID testing (probe under armpit for body temp and in ice water shows consistent temps of 98 and 32 degrees.)
I have some familiarization with PIDs as I had this one on my Lee pot for over two years, one on my Star, and one I installed in my Rancillio Silva Espresso machine.
I will investigate further and may put the old probe on it.
The ProMelt was turned all the way up on the dial past 850. I made a probe mount to keep the tip about 1" off the bottom and near to the spout. The pot was half full of lead and ran for quite a while and nothing was poured from it. The set point was at 700 and at times the temp would go over 800 (before tuning).
I noticed my PID was swinging very high and low, like a digital RPM gauge at times - temp readings that varied 150-200 degrees within 10 seconds. Seemed to do it if touched the top of the probe and "jiggled" it. Wouldn't do it if I stirred the lead.
I got the temp to settle around 700 so I went through the tuning process a couple times. It seemed to stabilize and the readout swings seemed to have disappeared,, even with the jiggle test.
My only thing now is that it doesn't get to 700...stays around 680-690 on the reading.
My PID worked just fine on my Lee 20 pot. I never noticed these rapid swings on the readout and it held the temp pretty much right on. I did change the K thermocouple from a high temp to another high temp with a 6"SST probe from Frozone. I double checked from him about polarity. No other wiring or settings were changed. PID testing (probe under armpit for body temp and in ice water shows consistent temps of 98 and 32 degrees.)
I have some familiarization with PIDs as I had this one on my Lee pot for over two years, one on my Star, and one I installed in my Rancillio Silva Espresso machine.
I will investigate further and may put the old probe on it.