Cisco Systems 4948E-F manual Input voltage is ≥ -38.25 VDC ±2.25 VDC

Appendix A Power Supply Specifications

300 W DC-Input Power Supply (PWR-C49-300DC)

Table A-6	300 W DC-Input Power Supply Specifications (continued)
Item		Specification
Power supply LEDs
INPUT OK		• 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:
		– 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.
		• 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.
OUTPUT OK		• 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:
		– 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.
		• Off—In chassis that are equipped with a single power supply,
		the OUTPUT OK LED is off when the power supply is turned
		off.
Power supply fan		• 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-7for inlet temperature ranges and corresponding fan
		speeds.
Weight		2 lb (0.9 kg)

	Catalyst 4948E and Catalyst 4948E-F Switch Installation Guide
OL-21561-02		A-13