Load cell in a hydraulic press application

Hello,
I have an in-line (compression-20k)load cell installed on a vertical hydraulic press. The cylinders stroke is checked at home or fully retracted with a prox and at full extension with a prox. It takes about 1.5 seconds to extend to the full extension and makes contact with a housing at about 750ms. I'd like to capture the load cell data from that point, initial contact, to the point where it bottoms out. Hoping to data log this info and notice imperfections in the housings width and depth. The load cell is a transducer techniques(LPO-20K) with a 10VDC exictation. This goes to a signal conditioner/display, Sensotec GM, which has two discrete relay outputs and a 0-5VDC analog output. I have wired the analog to my embedded IO and have setup a SCP to send the data to F8:, which also makes it difficult to data log. The output at when the press is max'd is the 12380#, which is 5.6 volts, so I picked 9175 for input max. Not seeing any updating of the analog as I cycle. I'd like to at least monitor this load at initial contact and at full seat to help prevent too much broaching or extrusion when we press a bearing.
Thank you
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Not seeing any updating of the analog as I cycle.

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It sounds like an RSLogix5000 setup. Analog inputs are probably not isolated. Does the Sensotec GM have an electrically isolated analog output? If not, you may need to use a common power supply for the load cell exicitation, Sensotec, and the analog input module. Another option is to out a signal isolater between the Sensotec and the analog input.

Useful info for me to provide, This is being used in a Micrologix 1100 with two analog inputs on the base unit(using RS Logix 500). The Sensotec display has an internally power supply for the load cell and the conditioned output. I guess I was expecting to be able to monitor my SCP online and see the numbers scale as the load cell is compressed. It appears to be capturing data on one scan and then because of my program not looking at the input again?

Why the load cell?

If your hydraulic press is responsible for process force, I would not use a load cell, but a hydraulic pressure transducer on the forward (pressure) acting cylinder. PSI x Area = Lbs Force

Why

Plastic said:

If your hydraulic press is responsible for process force, I would not use a load cell, but a hydraulic pressure transducer on the forward (pressure) acting cylinder. PSI x Area = Lbs Force

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Load cells usually respond faster and are more accurate. The problem with load cells is that they must be mounted out where they can be damage.

If pressure transducers are used you must use two, one at each end of the cylinder. Then each transducer must be scaled by the surface of the piston on that side. The problem here is that both pressure transducers must be sampled at the same time as a difference in sample time will result in errors.

The value isn't updating because of the IIM in Rung 7. You're using N7:10 as the Mask in that instruction, and then using N7:10 also as the source of the SCP.

The Mask value of the IIM is an argument for masking out updates of specific bits; it's not a destination. If you're bringing in an analog value you want the Mask to be FFFF (hex).

I recommend removing the IIM and using I:0.4 as the source for the SCP instruction.

The onboard analog inputs on the MicroLogix 1100 probably aren't going to update faster than the main routine, and the Input data table has been updates just prior to the Ladder File 2 being started.

Mr. Roach, oops I posted some "desparation logic" I had and have gone back to sourcing the SCP with I:0.4. I am afraid you are correct, I can't get a larger time slice for this input with the embedded analog.

The Sensotec outputs are at 100HZ, I will research to see if I install an expansion analog card if I can at least capture 10 points a second during the cycle.

Thanks
I discussed the load cell type, that I already had on the shelf, with five different transducer folks. All agreed that this type was designed and would work well in this application.