XI110208 Digital Input module clarification

[Mr_Wonder_Why]

Hi, Would like to seek for clarification here regarding this XI110208 module. The purpose of the Up's port is to supply 24VDC out to the peripherals? 

[CodeShepherd]

Please have a look to the official documentation of the module.

As the module does use 2-wire technique the U_P provides a supply voltage for e.g. external switches that is measured at the corresponding DI IN connection. I will check if we can make it clearer in the documentation.

Power supply for sensors or actors probably needs to be attached separately to the external devices, see maximum output current.

[Mr_Wonder_Why]

So you're saying that the Up port here is use to supply 24V DC to the corresponding peripherals that gives signal to the "DI" port? Will it work if my Up is used to just supply 24VDC to the other peripherals ?

lets say for this module, is it possible that i can use 1 wire-technique( just the DI port) , without connecting anything the "Up" port. 

[CodeShepherd · Accepted solution]

When you connect the ground of an external 24V power supply to the ground of the bus coupler/power module the IO is connected to, you can:

• leave U_P open and use the external 24V as input to DI IN.
• (not recommended) leave DI IN open and use U_P to supply externals as long as you keep the current values as low as needed. Beware that there is permanent fuse inside to prevent over current. But it would be easier to use power supply also connected to your bus coupler/power module.