Eric Nelson
Lifetime Supporting Member + Moderator
I have a question regarding the 1769-IF4 Analog Input Module (for the ML1500 PLCs). What is the purpose of the "ANLG COM" terminals? The manual states:
• All module commons (ANLG COM) are connected in the analog
module. The analog common (ANLG COM) is not connected to
earth ground inside the module.
Are they connected to ANYTHING within the module? Again, quoting the manual:
• Voltages on Vin+, V/Iin-, and Iin+ of the 1769-IF4 module must
be within ±10V dc of analog common.
This leads me to believe that the "ANLG COM" terminals connect to something, though the manual is unclear as to just "what" that something is...
It looks to me (from the wiring examples), that they're just used as a common connection for the power supply common. Any ideas? I'm just curious... -Eric
• All module commons (ANLG COM) are connected in the analog
module. The analog common (ANLG COM) is not connected to
earth ground inside the module.
Are they connected to ANYTHING within the module? Again, quoting the manual:
• Voltages on Vin+, V/Iin-, and Iin+ of the 1769-IF4 module must
be within ±10V dc of analog common.
This leads me to believe that the "ANLG COM" terminals connect to something, though the manual is unclear as to just "what" that something is...
It looks to me (from the wiring examples), that they're just used as a common connection for the power supply common. Any ideas? I'm just curious... -Eric