Rockwell Automation 1746-NI16V SLC 500 Analog Input Modules User Manual - Manual (Page 13)

Publication 1746-UM001A-US-P
Overview 1-3
General Diagnostic Features
The 1746-NI16 module contains diagnostic features to help identify
the source of problems that may occur during power-up or during
normal channel operation. These power-up and channel diagnostics
are explained in Chapter 6, Module Diagnostics and Troubleshooting.
The module communicates to the SLC 500 processor through the
parallel backplane interface and receives power from the SLC 500
power supply through the backplane. The +5V dc backplane supply
powers the SLC circuitry and the +24V dc backplane supply powers
the module analog circuitry. No external power supply is required.
You may install as many 1746-NI16 analog modules in a 1746 chassis
as the chassis power supply can support.
System Overview The NI16I can only receive current inputs. The NI16V can only receive
voltage inputs.
System Operation
At power-up, the module performs a check of its internal circuits,
memory, and basic functions. During this time, the module status LED
remains off. If no faults are found during the power-up diagnostics,
the module status LED is turned ON.
After power-up checks are complete, the module waits for valid
channel configuration data from the SLC ladder logic program
(channel status LEDs off). After configuration data is written to one or
more channel configuration words and the channel enable status bits
are set, the channel status LEDs are turned ON and the module
continuously converts the analog input to a value within the range
selected in the configuration word.
Hardware Feature Function
Channel Status LED
Indicators Displays channel operating and fault status.
Module Status LED Displays module operating and fault status.
Side Label (Nameplate) Provides module information.
Removable Terminal
Block Provides physical connection to input
devices.
Door Label Permits easy terminal identification.
Cable Tie Slots Secures and routes wiring from the module.
Self-Locking Tabs Secures module in the chassis slot.