Power connection to NI UMI 7772

[psdy]

Hi friends,

                 I am trying to connect a UMI 7772 to P70530 drive for controlling a stepper motor

In the instruction booklet which came along with UMI - 7772, it is written that  : after connecting +24V to V terminal and -ve lead to C terminal , the V terminal has to be connected to V_iso terminal and C terminal to C_iso terminal.   Just wondering if this means I really have to physically connect the V terminal  to V_iso and C terminal to C_iso on the NI UMI-7772 board?

The question arose since it seems redundant to do the connection externally, as it could have been easily connected internally at factory itself?

Thank you,

With regards,

Partha

[ben64 · Accepted solution]

Partha,

The Viso and Ciso are used to power external circuitry like sensor and switches and fault detection (I strongly recommand the use of an emergency stop switch). The 24V is used to power the UMI itself. If the external circuit use a voltage different from 24V you can set Viso to this voltage (in the range 5V to 30V). If you don't use external switch/sensor you must connect it as you said in your post, you can still power external devices but they will not be isolated from the UMI internal circuits and you can encounter ground loop issues. The connection is not made internally to have isolated power source available.

Ben

[psdy]

Hi Ben,

             Thank you for the explanation - my  confusion is now removed.

Regards,

Partha