Module status leds, I/o status leds, Table 17 module status indicators – Rockwell Automation T8423 Trusted TMR 35 - 120 Vdc Digital Input Module User Manual
Page 27: Trusted, Module t8423

Trusted
TM
Module T8423
Issue 15 Apr 10
PD-T8423
27
4.2. Module Status LEDs
There are six module status LEDs on the module front panel; three Healthy, one Active, one Standby,
and one Educated. The Healthy indicators are controlled directly by each module slice. The Active,
Standby, and Educated indicators are controlled by the FPU. The FPU receives data from each of the
module slices. The FPU performs a 2-oo-3 vote on each data bit from the slices and sets the
indicators accordingly.
The module status LED states and their meanings are described as follows:
LED
State
Description
Healthy
Off
No power applied to the module.
Amber
Slice is in the start-up state (momentary after installation or
power-up).
Green
Slice is healthy.
Red – flashing
Fault present on the associated slice but the slice is still
operational, or one 24V feed to the chassis has failed.
Red (momentary)
On installation – power applied to the associated slice.
Red
The associated slice is in the fatal state. A critical fault has
been detected and the slice disabled..
Active
Off
Module is not in the Active state.
Green
Module is in the Active (or Maintain) state.
Red – flashing
Module is in the shutdown state if the Standby LED is off.
Red – flashing
Module is in the fatal state if the Standby LED is also flashing.
Standby
Off
Module is not in the Standby state.
Green
Module is in the Standby state.
Red – flashing
Module is in the fatal state. The Active LED will also be
flashing red.
Educated
Off
Module is not educated.
Green
Module is educated.
Green – flashing
Module is recognised by the Processor but education is not
complete.
Amber - Flashing
Active/standby changeover in progress
Table 17 Module Status Indicators
4.3. I/O Status LEDs
There are 40 input channel status LEDs on the module front panel, one for each field input. These
indicators are controlled by the FPU. The FPU receives data from each of the module slices. The
FPU performs a 2-oo-3 vote on each data bit from the slices and sets the indicators accordingly.
The input status LED mode is dependent upon the voltage level of the field I/O signal. Each field input
voltage is measured and compared to six threshold levels (four configurable and two fixed) which
produce seven threshold bands. Each threshold band can be defined to have a particular indicator
mode: off, green, red, flashing green, or flashing red.