NI 9375 DI COM pin connected to earth ground?

[Temistocle]

Hi, I would use a NI 9375 to check the state of some digital swithces, in a circuit with a +24V power supply. Inside the 9375 the lower end of the receiver circuitry (DI COM) is connected to GND, but it is isolated from earth ground as stated in the manual.

Our +24V power supply has the "minus" pin connected to earth ground, and will be connected to DI COM..

Is there any problem for this connection? 

Thank you in advance

Temistocle

[santo_13]

Simple circuit diagram will help understand the question better.

[Temistocle]

Please, see the attached figure. On the right there is the internal circuitry of the 9375 inputs, with the DI COM connected to ground internally. But this pin is not connected to earth ground as stated in the manual:

"The bank of 16 digital input channels and the bank of 16 digital output channels on the NI 9375 are isolated from each other and isolated from earth ground." 

On the left there are the switches we need to monitor with the 9375 and the +24V power supply. The latter has the "minus" pin gounded to earth.

So, is there any problem if the 9375 DI COM inputs are connected to earth ground?

Thank you in advance