Siemens SIMATIC Rack PC 840 - Page 133

Hardware Information
7-25
SIMATIC Rack PC 840 Manual
A5E00104826-03
Assignment for Fan Supply, X41, X42, X43
Pin No. Designation Description Input / Output
1 GND Ground –
2 +12V Switched power supply Output
3 CPU FAN_CLK Speed signal for
monitoring
Input
Assignment for Uncontrolled Fan Supply, X40
Pin No. Designation Description Input / Output
1 GND Ground –
2 +12V Power supply Output
3 NC – –
Assignment for SCSI Activity Connector, X39 Type JST B2B-PH-SM3-TB
Pin No. Designation Description Input / Output
1 NC –
2 SCSI HD_N 0V levell means that SCSI
port is active
Input