Chapter 4 Troubleshooting 19
NetSure 731 A41 Subrack Power System User Manual
Chapter 4 Troubleshooting
This chapter describes the handling of alarms, as well as the routine maintenance of the system during system daily
operation.
The maintenance personnel must have adequate knowledge about the subrack power system.
Note
1. The maintenance must be conducted under the guidance of related safety regulations.
2. Only trained personnel with adequate knowledge about the subrack power system shall maintain the inner part of the subrack.
4.1 Controller Alarms And Fault Handling
The controller alarms are classified into three types: major alarm, observation alarm and no alarm.
Major alarm: This type of alarms have strong impacts on the system performance. Whenever these alarms are
generated, users are supposed to handle them immediately. The red major alarm indicators will be on.
Observation: When this type of alarm is raised, the system maintains normal output for a while. If the alarm occurs
during watch time, it should be handled immediately. If the alarm occurs during non- watch- time, handle it during
watch time. The yellow observation alarm indicators will be on.
No alarm: If alarms are set as
‘no alarm’ by the users, when these alarms occur, the green alarm indicators will be on
and the system works normally.
If an unnecessary alarm occurs during the operation of the controller, set it according to the following method.
Take the alarm of
‘Rect Lost’ for example:
For M221S/M222S controller: MAIN MENU
—
> Settings
—
> Alarm
—
> Alarm Control
—
> Clear
—
> For the submenu
of "Clear", you can select "Rect Lost" to clear corresponding alarm.
For M225S controller: Settings
Clear. For the submenu of
‘Clear’, you can select ‘Rect Lost’ to clear corresponding
alarm.
The handling methods of normal alarms are given in Table 4-1.
Table 4-1 Alarm description and action to correct
Index
Alarm
Handling method
1
Mains Failure
If the failure does not last long, the battery will power the load. If the cause is unknown or the failure lasts
too long, a diesel generator is needed. Before using the generator power to supply the subrack power
system, it is suggested to run the generator at least five minutes to minimize the impact on the subrack
power system
2
AC Voltage
High
Check if the AC over-voltage value is too low. If yes, change the value.
A mild over-voltage does not affect the system operation. However, the rectifiers will stop working
operation when the mains voltage is more than 305V. If the mains voltage is above the AC over-voltage
value, the mains grid should be improved
3
AC Voltage
Low
Check if the AC Under- voltage point is too high. If yes, change the value.
When the mains voltage is lower than 176V, the output power of the rectifiers will be derated. And if lower
than 80V, the rectifiers will stop working. If the mains voltage is under the AC under-voltage value, the
mains grid should be improved
4
SPD alarm
Check the SPD condition. If the SPD is damaged, replace it
5
DC Volt High
Check the DC over-voltage value through the controller. If the setting value is inappropriate, correct it.
Otherwise, find out the rectifier that has caused the alarm:
1. Ensure that the batteries can operate normally.
2. Switch off the AC input of all rectifiers.
3. Power on the rectifiers one by one.
4. If the over-voltage protection is triggered when a certain rectifier is powered on, that rectifier is the
faulty one. Replace it