Sensing DC voltages with NI 6528

Hi.

I have several questions about sensing DC voltages using NI 6258 Digital I/O module.

Below figure is a example of circuit configuration to measure the voltage with NI 6258 module.

Q1. "LOAD" should be located in the circuit to sense the voltage of supply?

Q2. If yes, what is the proper value of the load resistance?

Q3. When we assume that NI 6512 module is used as power supply, if there is no load in the circuit and switch is closed, NI 6512 can be broken?

p17, https://www.ni.com/pdf/manuals/372124d.pdf

Thanks,

Woohyun ahn