active and passive I/O tags and exact number of signals in DCS

Dear,

I got first query from client:

Prepare a comprehensive I/O list illustrating signal ( Tag Name, description, type , passive or active , power supply )

What does it mean to have passive and active I/O's included part of the I/O list?

another query from client:

"
Any calculation signals have to be considered within DCS to get the exact number of compactor’s signals"

I believe calculation signals will be involved only in programming / graphics in DCS but why do we need to exact number of compactor signals?

Thanks for your help!
Best Regards,

Charbel

Assuming we're discussing Fanuc's Dual Check Safety, DCS can be used in place of h/w signals for e-stop and fencing provided the robot is optioned with Profinet Safety or similar.

Dear jstolaruk,

thank you but do you know what it passive / active I/O's means?

all the best,

charbel

No, I'm sorry, I don't understand it myself.

Perhaps it may be best to ask the client these questions instead ?

In the 4-20mA world, passive is a 2 wire, loop powered signal where the power for the signal is connected in the loop, not to the device itself.

'Active' is an analog output powered by a power supply connected to the device, a 3 wire or 4 wire device.

Sizing a DC power supply requires knowing how many loads it can handle.

Active outputs tend to have more issues with ground loops, because of ground potential differences between the receiver (DCS) and the field device.

Thank you Dawn for your answer