SSR relay problem solution

[Avo Mk8]

For a matter of saving time in the long cooking process of the flasks and the goldsmith casting. There are heat losses from the opening door and the hole where the oven exhaust pipe is, perhaps trying to contain them using ceramic fiber or other heat resistant materials I could reduce the time.

Please don't ignore the PID tuning advice.
You need to find out if the longer heating time is due to the controller "slowing down" the heating as set temp approaches.
or it may be that it's just the time it takes because of the thermal mass of the oven and the power of the heating element.

The controller has to be set to balance power "= speed of heating" vs overshoot. If you don't want to exceed 800 deg, it will take longer to heat the oven than if it doesn't matter about overshoot. See illustration below. Have you looked into these settings?
There's plenty on the web about this if you haven't investigated it already.

 

[marconi]

Here is a youtube clip which explains how to set up the controller initially and then to select auto tune (AT) to optimise how the oven heats up and then regulates its temperature. It is the same controller as the one you have although it has a different name.

Here is leaflet on your controller but I recommend you use the YouTube clip first.

https://images-na.ssl-images-amazon.com/images/I/91cH5fgtECL.pdf

 

[mdkmdk]

I did as specified in the manual but the AT light always blink endlessly without ever stopping.

 

[marconi]

Look at 4 mins 18seconds onwards. Have you turned the derivative function on?

 

[James]

Also, remember it could take 2 to 3 hours to tune if your set point is really high.

 

[marconi]

The computer inside the controller is making small changes to the P, I and D values and then seeing how the oven performs in terms of oven temperature PV and its error when compared with the desired or set temperature SV all over time. Iteratively it will be homing in on the P, I and D values which give the best oven temperature PV time performance. When it has arrived at these values any changes away from them will make the performance worse each time which is how the controller knows when to stop auto tune.

 

[marconi]

I should have said that in order for the auto tune to work you will need to cycle your oven from cold to hot to cold, a number of times for the AT function to work and the light to stop flashing, before you use the oven for business.

I also need you to confirm you have turned the derivative or d function on.

 

[marconi]

mdkmdk - Would you mind letting us know your progress please?

 

[mdkmdk]

mdkmdk - Would you mind letting us know your progress please?

Sorry for the delay in answering, I did get it to 800 degrees centigrade but the auto tuning light was still flashing. I saw the video at minute 4.18, should I set the AL1 value, if so why?

 

[marconi]

Good you have been looking at the controller's settings. Would you go through the steps as in the youtube video and report to me the settings you find? I can then tell you what to change or keep the same.

More immediately please me tell if you have set up 'InP' value as 'k' ( see at 5m57s) to tell the device you are using a thermocouple - and then tell me if the 'd' function is set to on or off (see at 6m57s).