How many motors are connected?

[Evgueni]

Hello,

I am using two similar experimental set-ups with two motion controllers MID 7604/7602. The only difference between the set-ups is that there are 2 motors connected to one controller and 3 motors connected to the other controller. I would like to have the same software for both set-ups that could recognize whether 2 or 3 motors connected to the controller. Is there any way for me to find out using LabView programs how many motors are connected to the motion controller?

Thank you very much.

Evgueni.

[Jochen]

Hi Evgueni,

there is no direct way for the controller to detect if a motor is present or not, but depending on your system setup there might be some options:

1. If you are using a closed loop system (with encoders), you could do a short test move. If the encoder position changes accordingly you know that the motor is present.
   
   
2. If you are using limit switches (forward and reverse), you should make sure to use switches that are normally closed. If you configure the limit switch inputs correctly, the board should report "both limit switches are active", if no limit switch is connected. This should indicate, that no motor is connected, too.
   
   
3. If there are no encoders and no limit switches, you could use a limit switch connector that shorts the limit inputs to GND on the 760x and make it mandatory to use this connector for all axes, that should be active.
   
   
4. If none of the above methods work for you, you should think of a configuration dialog for your software and ask the user how many axes he wants to use.
   

There might be some more options but in general you will have to identify a signal that changes it's state depending if an axis is connected or not.

I hope this helps,
Jochen Klier
National Instruments

[Evgueni]

Thank you. This should help.

Evgueni.