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Spirent TestCenter: How can I resolve issue with "low voltage alarm" status on SPT-N11U power supply/slots or isolate the root cause of the problem?

Answer

The Spirent SPT-N11U mainframe chassis houses up to twelve slot power supplies that are accessible via the rear panel. There are three system power supplies for the system controller and fans that are not user serviceable.

Each slot power supply operates independently and is responsible for powering a test module in its designated slot.
 
For the SPT-N11U chassis with 110/220 V power supplies, there is one outlet per two power supplies. (for 110V, each outlet (power supply pair) it is recommended a separate 15 Amp circuit, when running on 220V, the difference is less current is required). The slot assignments for the power cords/sockets are labeled on the back of the chassis.
 
For the SPT-N11U chassis with only 220 V power supplies modules, there is one outlet per four power supplies.
 
This troubleshooting procedure is specified for SPT-N11U chassis with 110/220 V, however may be easily adapted SPT-N11U chassis with 220 V power supplies.
 
Warning: These power supplies are NOT hot swappable and power must be removed from the system before proceeding.
 
To clear “low voltage alarm” status on N11U power supply/slots, for example power supply 1, modules 1 and 2, take the following steps to resolve the problem on site or isolate the root cause of the problem:
 
1.        
  • first, ensure all power cords are fully inserted and securely fastened using the hangers
  • verify tools -> equipment information -> diagnostics -> chassis IP -> power supply status -> supply status needs to be normal   
2.        
  •  hot swap (as required) remove modules in slots 1 and 2
  • remove and reinsert power cord in power supply 1
  • verify tools -> equipment information -> diagnostics -> chassis IP -> power supply status -> supply status needs to be normal  
  • reinsert one card at a time waiting for first to boot
  • after each card is re-inserted, verify tools -> equipment information -> diagnostics -> chassis IP -> power supply status -> supply status needs to be normal  
3.        
  • if that does not resolve,  power down chassis (power off at the front, then remove the power cords at the back) reseat the power slot 1 and modules 1 and 2 (see attached procedure)
  • power up chassis (insert the power cords at the back, power on at the front)
  • verify tools -> equipment information -> diagnostics -> chassis IP -> power supply status -> supply status needs to be normal  
  • If yes, the issue is cleared, let’s monitor 
4.        
  • if that does not resolve, hot swap (as required) remove modules in slots 1 and 2 and a pair of working slots, for example slots 3 and 4
  • swap the power cords between power supply 1 (for modules 1 and 2) and power supply 2 (for modules 3 and 4)
  • this will help to isolate the issue to the power cord/external; supply or the power supply
5.        
  • if that does not resolve, power down chassis  (power off at the front, then remove the power cords at the back), change or interchange power supplies between modules 1 and 2 and modules 3 and 4
  • power up chassis (insert the power cords at the back, power on at the front)
  • verify tools -> equipment information -> diagnostics -> chassis IP -> power supply status -> supply status needs to be normal  
 
If that does not resolve, an RMA may be required.
 
Please reference attached document entitled “SPT-N11U Chassis Power Supply Installation Instructions”
Attachments
Attachment Description
SPT-N11U Chassis Power Supply Installation Instructions

Product : Spirent TestCenter,Chassis