temperature spread

[SimonTDK 0]

I'm working on a program for an industrial furnace.
On the oven there are X number of temperature sensors.

There must be a maximum difference of +/- 10 degrees Celsius, measured between two sensors, we call it temperature spread. If the difference between two temperature sensors exceeds 10 degrees Celsius, an alarm must be generated for my data collection system (bool).

Is the sysmac studio equipped with a function block that can do this?

Any help would be greatly appreciated

[BobLfoot 301]

It has been awhile since I worked with Omron PLC, {20+ years}, but I would propose placing your temp readings in a stacked array and running a for loop.  Compare Entry A to Entry A+1 and latch Alarm Bit A if the spread is greater then target.  Repeat for A+1, A+2 Alarm A+1 using the loop features

At the end you can or the alarms or do a non-zero compare to sound a master alarm for spread as well.

Hope what I am saying makes some sense.

[pcmccartney1 141]

I would think you would want to compare the new signal against the last known max and min, then at the end compare the max and min for the spread and generate the alarm.

[BobLfoot 301]

@SimonTDK --  @pcmccartney1 raises a good point.  I assumed you were looking for temperature variation over the length of the furnace with two adjacent sensors can't vary by more than 10C thus no heat shock transitions to the product as it moves through the furnace.  He is looking at furnace variation over time.  Your approach will be different for each case.

[SimonTDK 0]

In general my cycle for the oven is around 10-12 hours. During this cycle, two sensors can’t have a spread of more than 10 degrees Celsius. 
 

My first idea was to make my own function block for the task in hand. But I have to acknowledge my abilities, ain’t sufficient for the job. 
 

I might end up with contacting Omron field support for the job.