Looking for a manual for control techniques process instruments model 452

We have a control techniques process instruments controller model 452 that we are changing over to a eurotherm controller. We are looking for a manual for the controller so that we can get the parameters off of the unit and replace it. if anybody could help that would be awesome
 

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What do you need a manual for?

It's rare to find an ID label with that much configuration data.

It's obviously a temperature controller.

It's got two outputs, and since the heat/cool box isn't checked it's heat only.
So follow the cable to the final control element to see whether it's relay driven or 0-5Vdc driven

You don't know the control setpoint or the alarm setpoints, but for something this old, no one working wherever this thing is knows what setpoint they want to run and how much deviation they can tolerate on a load?

Assuming the old box did PID control, I'm guessing that whatever manual you might come up with (a scan of an old paper copy because this looks old enough to pre-date pdf) is not going to tell you how this particular furnace's(?) PID was tuned, because whoever did it wrote the tuning parameters on the inside cover of the original manual and a scan or pdf copy isn't going to have those particular notes.

The manual will only tell you that there's some adjustments somewhere, hysteresis for on-off or PI or PID adjustments. Look around for screw driver slots. If they're there, they'll be marked somehow.

If there are screwdriver pot adjustements, determine 'as found' position. Count the turns CCW until the adjustment bottoms out (the Brits drive on the wrong side of the road, but as I recall they usually got their pot adjustments right: increasing = CW. decreasing = CCW). Write the number down before you confuse with the other adjustments. Then count how many turns it takes CW to run the adjustment all the way up, to 'full scale'. Then take the found position as a proportion of the full scale to give you a starting point for tuning (0-1000% PB, 0-60min integral, 0-10 min rate, you'll find out quick enough if it's gain or reset in repeats per minute)

Or take a stab at manual tuning or run the autotune on the replacement controller.

The other information is right there on the label.
 
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