Vertiv NetSure-48 VDC Installation And User Manual page 33

12 Troubleshooting and Repair
12.1 Contact Information
Refer to Section 4154 (provided with your customer documentation) for support contact information.
12.2 Controller and Rectifier
For troubleshooting and repair instructions on these units, refer to the following documents.
•
NCU Controller Instructions (UM1M830BNA)
•
Rectifier Instructions (UM1R482000e3)
12.3 Controller Configuration
If any controller configuration settings were changed, refer to the NCU Controller Instructions (UM1M830BNA) and save a copy of the
configuration file. This file can be used to restore the controller settings, if required, at a later date.
NOTE!
Provided on a USB drive furnished with the system is a Controller Configuration Drawing (C drawing) and the
controller configuration files loaded into the controller as shipped.
12.4 System Troubleshooting Information
This system is designed for ease in troubleshooting and repair. The various indicators as described in "Local Controls and Indicators"
on page 26 and in the controller and rectifier instructions are designed to isolate failure to a specific element. Once the faulty element
has been identified, refer to "Replacement Information" on page 28 and "Replacement Procedures" on page 28.
Troubleshooting Alarm Conditions on the Controller
The controller displays alarm conditions as listed in the "Resolving Alarms" section of the controller's User Manual.
Active Alarm
The controller's
Instructions (UM1M830BNA) to access these menus.
Checking the Controller's Current Limit Point after Adding or Removing a Rectifier
If a rectifier module is added; the respective current limit point in amps will automatically increase to maintain the same percentage.
For example, if the current limit was set to 100% of combined capacity and a rectifier module is added, the new current limit setpoint
will be 100% of the combined capacity including the new rectifier module.
If a rectifier module is removed from the system (and the Rect Comm Fail is cleared), the current limit point will remain unchanged
unless the capacity of the remaining rectifiers is not sufficient to maintain this current limit point. If that happens, the current limit
point will automatically decrease to the maximum (121% of the remaining rectifiers).
It is recommended that the current limit point be checked whenever a rectifier is added to or removed from the power system.
When setting total rectifier current limit, the set point to each rectifier is the total set point divided by the number of rectifiers. For
example, if the system contains five rectifiers and the current limit is set to 150 amps then each rectifier has a current limit set point of
30 amps. If one or more rectifiers is removed or fails it will take several seconds for the individual set points to the remaining rectifiers
to be reset. In the example given, if one rectifier is removed the current limit set point will drop to 120 amps (30 amps times four
remaining rectifiers) until the controller can send updated set points to the remaining rectifiers. This takes a couple communication
cycles (several seconds) after which each rectifier would have a new set point of 37.5 amps for a total of 150 amps. The total current
limit of the rectifiers should not be set such that the loss of the redundant rectifiers will cause this temporary set point to drop below
the actual maximum expected load. If batteries are used on the rectifier output, the batteries should support the load until the current
limit set points can be re-established due to loss of a rectifier.
and Alarm History submenus allow the User to view alarm details. Refer to the NCU Controller
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Vertiv™ NetSure™ -48 VDC Bulk Output Rectifier System Installation and User Manual
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