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aTCA-80302PA/PD
7.1.2 AC PEM Signals
The AC PEM provides signals for:
• PSU output Voltage monitoring
• PSU output Current monitoring (Min.100W loading for each AC PSU)
• Fuse Monitoring
• Status of the Hot Swap Controller
• Temperature
The I2C devices on the PSU and AC PEM board are connected to Master-Only I2C-
bus of the Fan controller board. The Shelf Manager has access to these signals via
IPM-Bus of the Fan Tray.
7.1.3 AC PEM Indicators
The front panel includes a green and red status LED and a blue hot-swap LED.
Table 9: LEDs on AC PEM
Color
Description
Status
Condition
Green
OK LED
Off
No Power to the PEM
Solid green
Normal Operation
Red
Solid red
Attention Status (error condition)
Blue
Hot Swap LED
Off
No Power to the PEM or not OK to
extract PEM
Short blink
Preparing for extraction
Solid blue
Ready to remove
