Need pid device

The PID just sends the signal to the SSRs to open or close the circuit, so amps don't matter for the PID. Make sure the SSRs can handle it though. I got a ramp/soak controller from auberins, but I really wish I had something similar, as I only get it to temp and could do the timing on my own.
 
I would expect you'd need both a PID, a TC, and a SSR to wire up a complete PID control system
 
Do I need a pid that has manual operation and ramp soak operation or is ramp and soak version enough? D2, 01, 1095, ATS 34, 154CM, 440-C is what I will mostly use.
 
The unit I purchased from Auberins will Ramp/Soak and has manual operation. The ramp/soak are merely programmable capabilities of the unit.

Manual ops are ok for simple steels, but ramp/soak is necessary for your stainless heat treats. You have a mixed bag of steels so for a couple bucks more the ramp/soak is your best buy.
 
Craig Daniel said:
Do I need a pid that has manual operation and ramp soak operation or is ramp and soak version enough? D2, 01, 1095, ATS 34, 154CM, 440-C is what I will mostly use.
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As was mentioned, You also need a thermocouple (reads the temperature and sends that data to PID so PID can make adjustments) and Solid State Relays of the appropriate size. The SSRs actually take the high voltage and transfer it to the coils when the PID sends a 12v (low voltage) signal to them, telling them to do so.
 
Busto said:
The unit I purchased from Auberins will Ramp/Soak and has manual operation. The ramp/soak are merely programmable capabilities of the unit.

Manual ops are ok for simple steels, but ramp/soak is necessary for your stainless heat treats. You have a mixed bag of steels so for a couple bucks more the ramp/soak is your best buy.
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I have the same controller. How do you operate it in manual mode? I have been over the instructions many times. I would like to be able to just set it for my target temp and hold that temp until I stop it. I don't like leaving my oven unattended, so I don't really need or want (at this point anyway) to actually use the ramp/ soak function.
 
I'll make a brief explanation of what the process is. The instruction sticky for converting a toaster oven to PID control is basically the same.

1) Leave the existing oven as-is. In operation, you will just turn the oven power switch on, set the analog dial to "HI", plug the power cord into a socket run by the PID, and the PID will run things.

2) Make a PID controller that the oven will plug into. It will consist of a PID, a 40 amp SSR with a matching heat sink (the SSR needs a rating at least twice the actual draw), an 8 gauge TC ( normally type K), a TC connector block, type K TC wire, a set of type K TC plug and socket. You will also need a heavy duty 30 amp socket to match the oven power cord, and a 20 amp or higher rated ( I would use a 10 gauge cord) power cord for the control box. A single box (with a cooling fan) that has all these is the best setup.

3) The TC is placed in the oven in the area of the existing TC ( leave the old one in, too).

4) The TC connects to the PID (via the TC wire and plug/socket) and the PID runs the SSR.

5) The oven is plugged into the power socket that the PID turns on and off, the dial set to HI, and the power switch turned on. The PID does it all from there. The old analog temperature dial on the oven will still read, providing a second verification of the temperature.

The PID control box can run any device that can be connected to it. This makes future upgrades and builds much cheaper. You can riun a forge, a salt pot, a temper oven, etc. ... just by plugging in a power cord and a TC.
 
Don't forget also that you have to tune the controller PID loops for each temperature range you want to use. The Automation direct controller I use has 4 different PID loops that I have tuned in for different temperatures. The reason being is the PID loop for 400ºc, 800ºc and 1100ºc will be much much different form eachother. That way you will be ensured that you won't over-run or under-run the set temp. Hope that make sense.
 
brad72 said:
Don't forget also that you have to tune the controller PID loops for each temperature range you want to use. The Automation direct controller I use has 4 different PID loops that I have tuned in for different temperatures. The reason being is the PID loop for 400ºc, 800ºc and 1100ºc will be much much different form eachother. That way you will be ensured that you won't over-run or under-run the set temp. Hope that make sense.
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All I've read states you just auto tune for the lowest temp you intend to use. This in the manual for my PID.
 
Kevin McGovern said:
All I've read states you just auto tune for the lowest temp you intend to use. This in the manual for my PID.
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The problem with this can be to get to say 400ºc is a walk in the park for the oven and the controller will start pulsing the power to the elements very early to avoid over-run and pulse the elements for very short periods to avoid under-run. At 1100ºc the power needs to stay on longer and start pulsing much closer to the set point. If it starts pulsing too early it will take a long time to reach the final set point and when the set point is reached will need to pulse the power on for longer to avoid under-run once the setpoint is reached.

This has been my experience anyway and I will only get a few degrees over and under-run. for each temp I ran a PID cycle tune from cold.

Happy Grinding
 
brad72 said:
The problem with this can be to get to say 400ºc is a walk in the park for the oven and the controller will start pulsing the power to the elements very early to avoid over-run and pulse the elements for very short periods to avoid under-run. At 1100ºc the power needs to stay on longer and start pulsing much closer to the set point. If it starts pulsing too early it will take a long time to reach the final set point and when the set point is reached will need to pulse the power on for longer to avoid under-run once the setpoint is reached.

This has been my experience anyway and I will only get a few degrees over and under-run. for each temp I ran a PID cycle tune from cold.

Happy Grinding
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I have not found this to be the case with my set up. I believe the documentation I have says to autotune to the lowest temp you intend to use because overshoot is way more likely at low temps. At 1950°F my oven creeps up to temp. Like 1 degree every 5-6 seconds or so.
 
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