Honeywell 900U02-0100 - Page 219

Revision 10 ControlEdge HC900 Process & Safety Controller User and Installation Manual 205
May 2019
Channel
Type
Failure message
indicated on Honeywell
OI or Honeywell
HCDesigner/Utilities
function block monitor
Description
User Action
Failing to convert
When attempting to take a reading, the
ADC fails. This could result if the incoming
signal is either too large or small. It also
could result if the ADC circuit is failing. If
the problem is the ADC circuit, most likely
other channels will have the same failure.
Check the signal level being
applied to the terminals.
Replace module.
AO
Bad Channel
The board indicates that the channel is
failing to output the correct value.
Check terminal connections.
Replace module.
DO
Bad Channel
The number of configured channels in the
DO function block exceeds the number of
hardware channels on the DO card.
Reconfigure the DO function
block.
Replace DO card with correct
number of channels.
UIO
channels
Openwire
Either field wire is open or channel HW is
open
Check the field wiring
Short circuit
Either field wire is shorted or channel HW
inside module is shorted
Check the field wiring
Readback fail
IO module is not able to drive output
1. Check load is within
supported range
2. Check field wiring
3. Restart module
4. Replace module
Input compare fail
AI/DI voting failing within module
1. Restart module
2. Replace module
External field supply failure
Field supply voting is not within supported
range
1. Check the field supply
voltage
2. Check field supply wiring
ECxx where xx is a number
IO module detected internal HW fault
during self-diagnostics
1. Restart module
2. Replace module