Controlling A-B 160 VFD

I have been asked to modify a system that is using 4 AB 160 drives; which controls 4, 3 phase 480vac motors by 10k pots, using 4-20ma; to be controlled by a panelview 600(touch screen only). The run/stop is controlled through the plc. We want to use a preset menu to set the drives at a preset speed, but we also want to be able to adjust the speed manually while we are in production. I am using AB slc 5/04 with RSlogix 500, and I'm using a analog output card for the control. I don't know how to write the program for it, I'm a troubleshooter not a programmer(yet). I can write simple program but this a little harder for me.

The motors are used for conveyors and are 3-1hp, and 1-1.5hp. The drives are 2-2hp 4.6a, and 2-3hp 7a.


I have tried to search past threads before I posted, but I didn't see anything that would help me.

Thanks in advance,

Sounds like you need say 3 preset speed values,
plus a seperate one for production

cjd1965 said:

Sounds like you need say 3 preset speed values,
plus a seperate one for production

Click to expand...

How do I write that? If the presets are let's say 14.5ma how do I tell the analog card to output that? The data entry is incremental/decremental. This is my first shot at this and may seem like an easy task, but not for me. Thanks again.

Your output channels on the analog card have scaling values. A min and a max. Lets say min=0 and max=4095, then to produce a 50% or 12.5mA you would write a value of 2048 into the output (4095 x 50%), 1024 for 25% and so on.
The speed pots would add to the complexity, but not much. Can you use the panelview to replace these pot's?

imautomated said:

Your output channels on the analog card have scaling values. A min and a max. Lets say min=0 and max=4095, then to produce a 50% or 12.5mA you would write a value of 2048 into the output (4095 x 50%), 1024 for 25% and so on.
The speed pots would add to the complexity, but not much. Can you use the panelview to replace these pot's?

Click to expand...

We are replacing the pots with mod. Thanks for your help.

Use the manual for your analog output card.

You will find scaling values to be able to calculate the correct milliamp output for each channel.

You will also find how to configure the card for the range you want. For 4-20mA you will use the values 6242 to 31208 in the SLC.

Investigate the SCP instruction which makes the math easier for you.

You can for example, scale the panelview data from 0-90Hz, (program the drive min and max speed for those values) and in the SLC, use SCP to scale the entry from 0 to 90 to the range 6242 to 31208 with very little pain on your part.

If you want to use percent of full speed 0-100, then the panelview operator need not understand Hertz, and you can keep it independent of the drive settings.

Paul
EDIT: I originally had scale values for current inputs, and changed them to be correct for current outputs...