Cisco 4948 - Catalyst Switch Installation Manual page 89

Appendix A Power Supply Specifications
Table A-6
Item
Power supply LEDs
INPUT OK
OUTPUT OK
Power supply fan
Weight
OL-21561-02
300 W DC-Input Power Supply Specifications (continued)
Specification
Green—The INPUT OK LED is lit green when the power
•
supply has detected that the source DC voltage is within limits.
The input voltage is ≥ –38.25 VDC ±2.25 VDC.
Red—The INPUT OK LED is red when either of the following
•
two situations occurs:
–
–
Off—In chassis that are equipped with a single power supply,
•
the INPUT OK LED is off when source DC voltage falls below
33 VDC (±3 VDC), is not present with the power on/off switch
turned on, or the power supply is turned off.
• Green—The 12 VDC output is within margins (11.30 VDC <
output voltage < 12.85 VDC).
Red—The OUTPUT OK LED is red when any of the following
•
three situations occurs:
–
–
–
Off—In chassis that are equipped with a single power supply,
•
the OUTPUT OK LED is off when the power supply is turned
off.
One temperature-controlled, variable-speed fan
•
Airflow direction—Back to front
•
The power supply fan has four speed settings. The speed
•
settings are dependent on the inlet air temperature. See
Table A-7
speeds.
2 lb (0.9 kg)
Catalyst 4948E and Catalyst 4948E-F Switch Installation Guide
300 W DC-Input Power Supply (PWR-C49-300DC)
In chassis that are equipped with dual power supplies, and
both power supplies are powered on, the INPUT OK LED
is lit red if its source DC voltage falls below 33 VDC
(±3 VDC).
In chassis that are equipped with dual power supplies and
one power supply is powered on and the other power supply
is powered off, the INPUT OK LED is lit red, rather than
unlit, on the power supply that is turned off.
In chassis that are equipped with a single power supply, the
12 VDC output is out of tolerance (less than 11.30 VDC or
more than 12.85 VDC).
In chassis that are equipped with dual power supplies and
one power supply is powered on and the other power supply
is powered off, the OUTPUT OK LED is lit red, rather than
unlit, on the power supply that is powered off.
The OUTPUT OK LED is also lit red when a power supply
fan failure is detected. A fan failure is triggered when the
fan rotation drops below 4150 RPM ±150 RPM.
for inlet temperature ranges and corresponding fan
A-13