12.5.6Power
Power is supplied through the
Four 12 volt pins provide +12 volt power to the drive. The current return for the +12 volt power supply is through the common ground pins. The supply current and return current must be distributed as evenly as pos- sible among the pins. The maximum current typically occurs while the drive motor is starting.
Three 5 volt pins provide logic power to the drive. The current return for the +5 volt power supply is through the common ground pins. Distribute supply and return current as evenly as possible among the voltage and ground pins.
The mating connector pins use shorter contacts to achieve power surge reductions and to aid in “hot plugging” the drives. There are longer voltage contacts in the connector to enable the drive filter capacitors to charge. Current to the drive through the long charge pins is limited by the system in which the drive operates. Three of the +12 volt pins are shorter to allow capacitive
12.5.7Fault LED Out
The Fault LED Out signal is driven by the drive when:
•the drive detects failure of both ports
•the drive detects an internal failure
•the drive receives the appropriate fault LED command from the host
The Fault LED Out signal is designed to pull down the cathode of an LED. The anode is attached to the proper +5 volt supply through an appropriate
68 | Cheetah 15K.7 FC Product Manual, Rev. C |