Installation manual
Authorized Service Personnel ONLY:
Power Supplies 
Power the COS unit up by plugging it into a power source. There is no power switch. 
On the Power Supply Cards, check that the green “Power Good” LED is lit and the Red 
“Halt” LED is not lit. If this is not the case, replace the power supply.
Hot Swap LEDs 
On the Controller Front Card and any Switch Front Cards installed, there are three hot- 
swap control LEDs. These consist of a green “OK” LED, a yellow “Fault” LED and 
a blue “OOS” (out-of-service) LED.  Only the green “OK” LED should be lit.  These 
lights can be interpreted as follows 
OK
Fault
OOS
Meaning
On
Off
Off
Operating normally.
On
On
Off
Temperature, Voltage or Current condition is out of tolerance, still operating.
Off
On
Off
A failure has rendered the card inoperable.
Off
Off
On
Front or rear card is partially ejected or software has disabled the card.
Off
Off
Off
Boot code running, power not been applied to chassis or the card is fully 
ejected.
No other combinations should be possible and indicate the card is not operational. 
The  blue  “OOS”  LED is duplicated  on  the  Rear  card  for  ease  of  use during  card 
exchanges. 
Faults 
The Controller Card’s “Fault” LED will come on and stay on if a problem is detected, no 
matter how briefly. The operator must intentionally clear the fault condition. A fault can 
occur if any of various measured values fall outside normal operating conditions.  The 
unit monitors current, temperature and all voltages in the unit. It also monitors the health 
of the internal microprocessors and the functionality of the software. 
If the fault is not critical, the COS will continue to operate and display the green “OK” 
LED.  If the failure is critical (the card can not operate in this state), the green “OK” 
LED will go out and the device will not communicate via any interface.  Critical failures 
would include serious over current or significant failure of the main voltage rails. 
To clear a critical or non-critical fault, the operator can temporarily 
flip 
the ejector latches 
on the card. Or, the state can be cleared via Ethernet or serial control. 
Out-of service (OOS) LED 
The out-of  service  LED  indicates  the  card  is  partially  ejected  or  the  operator  has
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