Sun Microsystems 820-4733-10 Troubleshooting Power Supplies, Powering Off Power Supplies

3.1Troubleshooting Power Supplies

The status LEDs on the power supplies can help you determine the problem with the power supplies. See TABLE 3-1.

TABLE 3-1Power Supply Status LEDs

Glyph	Name	Color	State and Meaning
	Active	Green	On – Power supply enabled, 12 VDC is supplied.
			Off – Power supply disabled, 12 VDC is not supplied.
			Flashing – No function.
	Attention	Amber	On – Fault detected, 12 VDC shut down
			Off – No faults detected
			Flashing – No function
	Connected	Green	On – Correct AC input voltage is present.
			Off – No input voltage
			Flashing – Incorrect AC input voltage.

Additionally, the showpresent and psustatus commands can provide some information.

3.2Powering Off Power Supplies

Power supplies can be brought from full power to standby state, using the disablepsu command. For example, to bring power supply 0 (PSU0) to a standby state:

#disablepsu 0

Using psu i2c addr 0x5d PSU 0, 12 V is off

#

The power supplies are only fully powered off when they are disconnected from the facility power. This is possible by:

■Disconnecting the power cord for the power supply

■De-energizing the respective circuit breaker for the power supply

3-2Sun Datacenter Switch 3456 Service Manual • August 2008