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Power Supply/Midplane Troubleshooting
A6 Power Supply Description
Fuse
The A6 Power Supply has no user replaceable fuse. While there is a fuse 
internal to the supply this is not meant for field replacement. If the internal fuse 
is blown, the power supply has experienced a major failure and should be 
replaced.
Standby Supplies
The A6 Power Supply assembly has two standby supplies that should always 
be on if the AC input voltage requirements are met. These are the +15V STBY 
and the +5.1V STBY supplies. These supplies are used by the instrument to 
keep certain circuits alive even when the power is turned off.
Over Current Protection
The A6 Power Supply assembly has built in over current protection that will 
shut down the supply if current draw from the instrument is too great. The 
power supply will remain on in an over current state for a minimum of 1 
second. The power supply shall turn off no later than 5 seconds after beginning 
the over current state. The power supply shall remain off until the line voltage 
is removed and then reconnected or the front panel power switch is cycled. 
Over current shut down does not apply to the standby supplies, the fan 
voltage, and the +32V A supply.
Thermal Protection
The A6 Power Supply assembly will protect itself by shutting down if it 
overheats. It will also reset itself with no user interaction after the temperature 
is reduced by approximately 10 degrees C.