Scaling output for VFD speed control.

Hi all,
I'm using a Micrologix 1500 and a 1769-OA16 Analog Output.
I'm trying to control the VFD frequency from the PLC.
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The VFD is a ABB ACS350, and I set the following parameters:
1103 (1) AI1
1104 (10 hertz)
1105 (60 Hertz)
1301 (20% which is 4 MA)
1302 (100% which is 20MA)

[/FONT][FONT=verdana, courier new,courier,tahoma,sans-serif]S1(in the VF1) is set onthe top position for AI1[/FONT].
B[FONT=verdana, courier new,courier,tahoma,sans-serif]ut the VFD frequency was always 60 Hz[/FONT], no mater the values in the PLC (N10:22)

[FONT=verdana, courier new,courier,tahoma,sans-serif]Then I changed switch S1(in the VF1) to
the top position for AI1, and I was able to change the frequency, but not
reflecting the input values.
For example:
Input=10, Frequency=42
Input=35, Frequency=52
Input=60, Frequency=60 [/FONT]
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What I'm doing wrong? [/FONT]

Elcan said:

Hi all,
I'm using a Micrologix 1500 and a 1769-OA16 Analog Output.
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What I'm doing wrong? [/FONT]

Click to expand...

Are you sure about that output module catalog number?
1769-OA16 is not an analog output module its a AC 100 to 240 volt
solid state discrete output module.

Post your code.

With the yellow switch set toward the middle of the drive (away from the edge), you will get 10hz at 4ma and 60hz at 20ma with the settings you listed. Only look at 2007 and 2008 to be sure they are set at 0 and 60 respectively.

Now, your only challenge is getting the 4-20ma signal into the AI1 input.

Can't help you on the PLC side.

Thank you for your responses. I will check those parameters.
Mickey, you are right, my card is a 1769-OF8C.

Output Values will depend on how you have the card configured. See PDF below.