In an Analog I/P module- for no of Inputs- 16 single ended, 8 differential or 4 High-speed differential means....I need the clear and exact explanation for the clarification mentioned here.

 

The input card can be configured for three different modes.
1. as a 16 point analog input where all input signals are reference to the same ground.

2. as an 8 point isolated/differential analog input where each signal is referenced to it's own ground connection.

3. as a high speed four point isolated/differential analog input where each of four inputs is sampled at a higher rate than normal.

"differential" just means that the difference between the signal and the ground reference is being read in from the module.

 

bindhu,

In Allen Bradley (1771) and probably others,

16 single ended - all transmitters are loop powered (one common power supply, 2 wires to the transmitter), low common mode rejection (lower volage isolation between channels, lower noise rejection).

8 differential - multiple transmitters are instrument powered (multiple power supplies, 4 wires to the transmitter) higher common mode rejection (higher voltage isolation between channels, better noise rejection).

4 High-speed differential - cannot comment.

Rob Barrese