How to use a VSD (Omron 3G3SV) with a Omron CPM1

Hi everyone

I need to connect a variable speed drive to control the voltage output in a Omron CPM1 PLC. In order to do that i think i should use a MOV instruction then a CMP instruction but i can't do it...
The purprose of the job is to control a ventilation system, when the concentation of CO2 is greater than a value of reference the Ventilation system must turn on. When the concentration is 500ppm the output must be 2,5 V and when is 1000ppm the output must be 5V. The output voltage must be proportional to the CO2 concentration....

Help Please

Jose Gouveia
Electrotechnical Engineer Student
University of Coimbra

The CPM1 will require an expansion module (CPM1A-MAD01).

The expansion module will add two analog inputs and one analog output.

You will need to properly configure the MAD01 for the type of input and output signals you require.

Addressing will depend on your current configuration, model number of CPU unit and what if any expansion modules are currently installed.

Hope this will help.

thanks for the quick answer

i have already configure properly the exapansion but i can't do the ladder program in the part that i need to configure the output...
i don't know how to do make the output alternate proportinally with the signal received in the analog input
what instruction do i have to use?

Based on the limited instruction set of the CPM1, you will probably need to scale the value using math instructions.

This may take a bit of trial and error, but it should work.

You will want to download a copy of the W353 Programming manual.
Be careful, some of the instructions will not work with your CPM1. This manual covers CPM1, CPM1A, CPM2 and SRM1 units.

Hope this will help