Safety Circuits; Peration Vs . Channel Operation; Power-Up Diagnostics - Spectrum Controls 1769 User Manual

4-2 Chapter 4: Diagnostics and Troubleshooting
Module
Operation vs.
Channel
Operation
Power-Up
Diagnostics
At module power-up, a series of internal diagnostic tests are performed. If these diagnostic tests are not
successfully completed, the module status LED remains off and a module error is reported to the
controller.
User's Manual Pub. 0300241-02 Rev. A

4.1.4 Safety Circuits

Circuits installed on the machine for safety reasons, like over-travel limit
switches, stop push buttons, and interlocks, should always be hard-wired to the
master control relay. These devices must be wired in series so that when any one
device opens, the master control relay is de-energized, thereby removing power
to the machine. Never alter these circuits to defeat their function. Serious injury
or machine damage could result.
The module performs diagnostic operations at both the module level and the
channel level. Module-level operations include functions such as power-up,
configuration, and communication with a 1769 bus master, such as a MicroLogix
1500 controller, 1769-ADN DeviceNet Adapter, or CompactLogix controller.
Channel-level operations describe channel related functions, such as data
conversion and over- or under-range detection.
Internal diagnostics are performed at both levels of operation. When detected,
module error conditions are immediately indicated by the module status LED.
Both module hardware and channel configuration error conditions are reported to
the controller. Channel over-range or under-range and open-circuit conditions
are reported in the module's input data table. Module hardware errors are
typically reported in the controller's I/O status file. Refer to your controller
manual for details.
If module Indicated
status LED condition:
is:
On Proper
Operation
Off Module Fault
Corrective action:
No action required
Cycle power. If condition persists, replace the
module. Call your local distributor or
Rockwell Automation for assistance.