Digital Infrared Thermometer

[daboone]

This is awkward... but what is PID? When I google it I get "Pelvic Inflammatory Disease" - I'm sure that's not what you guys are referring to...

Take a look at this thread: http://www.lee-loader.com/viewtopic.php?f=31&t=1444

[farmerjim]

Proportional integral derivative controller.In bullet casting it is used to control temperature (lead pot, oven, lube heater) with much more precision than a standard thermostat.

[jloader]

This is awkward... but what is PID? When I google it I get "Pelvic Inflammatory Disease" - I'm sure that's not what you guys are referring to...

Take a look at this thread: http://www.lee-loader.com/viewtopic.php?f=31&t=1444

That is some great stuff here!!!!! Thanks a million!!!
That will probably be a nice project for me in ... spring I guess... I've found most of those parts on amazon for similar price. Now to set some founds and time aside...

[Ohio3Wheels]

The probe on my PID doesn't interfere

This is awkward... but what is PID? When I google it I get "Pelvic Inflammatory Disease" - I'm sure that's not what you guys are referring to...

i'm not certain I ever knew what PID stands for in this context. It's and electronic device that uses a temperature probe in the pot and a solid state relay to control the pot and hold it at the selected temperature usually +/- 5 degrees or so. They are neat devices and if I could find one that would throttle my gas burner I'd have one on my pot.

Make smoke,

[farmerjim]

quote "They are neat devices and if I could find one that would throttle my gas burner I'd have one on my pot."
No problem. Just put a furnace solenoid valve in the gas line. Use the PID and relay to open and close the valve.

[GasGuzzler]

I'm confused. You run a PID without a temp probe? The bar you talk about mounts exactly like my temp probe only I didn't have to make the probe like you would with a bar.

Mount



Probe (usually left in the lead to harden)

[daboone]

I'm confused. You run a PID without a temp probe? The bar you talk about mounts exactly like my temp probe only I didn't have to make the probe like you would with a bar.
Probe (usually left in the lead to harden)

No like you I leave the PID probe in the pot. I was referring to a possible way to obtain infrared readings. I don't have an infrared gadget so I don't know squat about them. I was just responding to the OP initial question.

I actually have two others type probes. One for the lube sizer and another for the toaster oven use for powder coating. The lube sizer probe is merely stuck on the side of the lube chamber. The toaster oven probe is a lot smaller version of the pot's immersion probe. So for me the PID controller has been very useful.

[GasGuzzler]

Got it.

(Off topic but my lube heater and its temp probe are mounted in an aluminum plate under my LAM)

[MikeW1]

Below is a copy of someone else's post from quite awhile back. I don't have his knowledge or experience but read it and suit yourself. I didn't replace my mine when it died FWIW.

Before I retired from Zeiss, at least 2-3 times a year I had to engineer systems
that would measure the exact temperature of machined parts prior to
measuring their dimensions. (Engine blocks, heads, etc. in Big 3 auto plants.)
So I've done more than my share of study of temperature measurement
methods. Let me say categorically that these non-contact "laser" measurement
systems are almost worthless. They measure infrared radiation from the target,
and that radiation varies wildly with what is called the "emissivity" of the
surface. The industrial suppliers of these things claimed that they could tell me
a temperature within 2-3 percent of displayed value, IF we sent a large
number of samples to them so they could measure the emissivity and calibrate
their sensors. Any time a sensor required replacement, they had to go through
the whole rigamarole again. Any time the surface finish changed, ditto.

Without calibration, and given unknown surfaces, they wouldn't guarantee
accuracy to better than 25% of the displayed value! And that's industrial
grade equipment costing thousands of $$. Bottom line, if you calibrate a
Harbor Freight instrument against an accurate contact thermometer, you may
be within 5% for the exact object you calibrated for. Any other object, you
can be wildly off.

BTW the laser has nothing to do with the measurement process. It's just an
aiming aid.

Best method is a low-mass thermocouple or RTD device, (thermistor).
These are not expensive. Some under-$100 Volt-Ohm-Meters come with a
thermocouple probe. I have had two of these, and they worked pretty well.
I've never stuck one into melted lead, but there are versions that are
encapsulated in ceramic which I would.