Highest Value

[[email protected]]

Is there a way to record the highest value in a certain time frame?
For example an analog input card.

 

[OkiePC]

Yes.

Tell us some specifics so we can tell you how to code for your PLC.

 

[[email protected]]

I am using a Micrologix 1400. With an analog input card. I am using a 4-20ma AC Current Transducer. I am wanting to measure the highest load on a cutting tool during the time that the tool is cutting.

 

[dskohio]

I would use a Greater Than comparision to compare the current value to a stored value, and if true then move current value to stored value. This way you will get the maximum value. You can reset the maximum value by moving zero to the stored value whenever you need to (based on time, shift start, new part, etc..)

 

[[email protected]]

hmmmm. Thank you.

 

[[email protected]]

OK same situation, but I am trying to get my scp function correctly setup.

I am also trying to get a correct reading and I am comparing it to my fluke amp clamp. Is there a cheat sheet?

 

[OkiePC]

Show us what you have in your SCP block and tell us what analog input you're using (the raw values may vary from one input type to the next).

 

[[email protected]]

OK I have an Automation Direct AC Current Transducer Part Number ACT050-42L-F 4-20mA. I have a Micrologix 1400 with an analog Input card.

Input is I:5.1
Input Min is 0
Input Max is 16383

Scaled Min is 4mA
Scaled Max is20mA
output to n7:0

 

[OkiePC]

Is your analog card model 1762-IF4?

If so, see here:
http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1762-in012_-en-p.pdf

That module can be configured for voltage or current via dipswitches (defaults to current).

It can also be configured through software to scale into engineering units, raw/proportional data or scaled-for-PID.

 

[TConnolly]

Your SCP scaled min/max should be set to the range of the variable you are measuring, not the analog output range of the transmitter.

The current transducer has a jumper selectable range of 10, 20, or 50 amps. If you want to know AMPS then your scaled min should be 0 and the scaled max should be whatever you have the jumper set at, 10, 20, or 50. If you want to know percent then scaled min should be 0 and scaled max should be 100.

Your input min/max depend on how you have the card configured. The input min will be the value the card returns when the input is at 4mA and the inputx max will the the value the card returns when the input is at 20mA. You can find those values in the manual OkiePC linked to.

 

[Mickey]

OK same situation, but I am trying to get my scp function correctly setup.

I am also trying to get a correct reading and I am comparing it to my fluke amp clamp. Is there a cheat sheet?

See attached below

 

[[email protected]]

My input data reads 29951

input min is set at 3277
input max is set at 16384

scaled min 0
scaled max 10

output reads 20

Is that 2 amps or 20 mA or?

 

[[email protected]]

sorry last post was incorrect

input data should read 9550
min same
max same
scaled min same
scaled max same
output now reads 5.

Amp clamp reads 6mA.
Is this accurate?

 

[Mickey]

sorry last post was incorrect

input data should read 9550
min same
max same
scaled min same
scaled max same
output now reads 5.

Amp clamp reads 6mA.
Is this accurate?

Tell us the analog card you are using (complete catalog number). Also tell us how your AC transducer is scaled. What does the 4-20ma represent?
Tell us how you have setup the analog card. If possible post your program
the .RSP file ( zip it first, then post)

 

[[email protected]]

I maybe wrong on amp clamp reading. It read .6amps so that would be 600mA?