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General => Technical support => Topic started by: Bill on February 15, 2011, 05:59:37 AM

Title: 0-100khz frequency out
Post by: Bill on February 15, 2011, 05:59:37 AM

Gentlemen,

Can you recommend a simple way of accepting an analog input of 0-10Vdc and converting the signal to a frequency output of 0-100Khz using the tri-plc?  I will need to be able to trim the frequency as needed to achieve the desired output.

Title: Re:0-100khz frequency out
Post by: support on February 15, 2011, 07:06:11 AM

If you use a Nano-10, FMD or F-series PLCs you can set the PWM output frequency from 50Hz to 50KHz which is the maximum range that it can support.

For Nano-10, you can simply connect the 0-10V analog voltage via a 20K ohm series resistor to convert it into 0-5V analog voltage that the PLC can accept and a very simple program can be written to convert the analog input readings to PWM with varying frequency.

Title: Re:0-100khz frequency out
Post by: Bill on February 15, 2011, 08:59:22 AM

Thank you.  

I see the PWM output is 24Vdc.  My drive accepts differential, bipolar inputs at a level of 5V.  Is there a recommended way to reduce the 24v to 5v?

Title: Re:0-100khz frequency out
Post by: support on February 17, 2011, 07:17:12 AM

Please refer to to Section 11.4.1 and 11.4.2 in the Nano-10 User's Manual that you can download from:

http://www.tri-plc.com/documents/Nano-10-UserManual.pdf

Two way of interfacing the 24V PWM outputs to 5V or 6V circuits are shown.

Title: Re:0-100khz frequency out
Post by: Bill on February 23, 2011, 08:53:38 AM

Thanks very much for the assistance!