Omni 4000 Series Installation Manual page 161

Abnormal
PSU green LED not PSU green LED, +24 V (D6)
illuminated and +5 V (D7) illuminated (AC
powered)
Flow Computer will not For unit powered by 24 VDC,
power on AC the large green LED is off
(DC powered)
Page 7-2
OMNI 4000/7000 Installation Guide – Rev H
Normal Possible Causes
Power, fuse, or line problem
Faulty field wiring is loading down the
system
Power, fuse, or line problem
Faulty field wiring is loading down the
system
Troubleshooting
System Power
•
Try DC power, if available, to
determine if the AC power source
malfunctioned.
•
If the flow computer does not power
on, replace the PSU.
•
Remove All I/O and communication
cards. With just the front panel, CPU,
and PSU connected, reapply power.
•
If the flow computer powers on, then
power the unit off and inspect and
install each I/O board one at a time.
•
If the flow computer does not power
on, replace the PSU.
•
Use a spare power supply for
troubleshooting.
•
If the flow computer does not power
on, check the fuses and lines.
•
Remove All I/O and communication
cards. With just the front panel, CPU,
and PSU connected, reapply power.
•
If the flow computer powers on, then
power the unit off and inspect and
install each I/O board one at a time.
•
If the flow computer does not power
on, replace the PSU.
Suggested Action