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Front:
• Health – Green indicates the PSU is Healthy,
Amber designates a fault
• AC Present – When illuminated, indicates that
AC is detected and within tolerance.
• DC Present – When lit, shows that PSU is
supplying DC to the chassis.
Rear:
AC Present – When illuminated, AC detected
Figure 6 – PSU Fault LEDs in green
Troubleshooting Tips:
• If the Rear AC Present LED fails to illuminate:
o Check to make sure the PSU in the front of the chassis is installed in the correct slot and is fully
seated.
o Verify that the power cable is installed in an operating AC outlet/PDU
• If the Rear AC Present LED is illuminated but the Front AC Present LED is not:
o Verify that the AC power being provided by the utility is within tolerances.
• If the Health LED is Amber the PSU has a fault and needs to be cleared.
o Remove the PSU for a minimum of 30 seconds.
o Verify that nothing is obstructing the front outlet and the rear PSU pins are not damaged.
o Re-insert the PSU and verify that it is fully seated.
o If the Health LED blinks Amber multiple times and then turns off, PSU is indicating a capacity
mismatch. Likely reasons for this are:
▪ PSU is connected to a different input voltage than the other PSUs (ex. 110 VAC instead of
208VAC).
▪ Input power power provided by the utility is not consistent or within tolerances.
Tolerances: 220VAC (single PSU runs 180V – 264VAC) or 110VAC input.