RT9 Powershelf
Rectifier Technologies
158-1806-01.doc
35
2-Mar-06
6. Troubleshooting
Symptom Likely
Causes Action
Rectifiers do not power up – no LEDs lit on
front panel
AC power is not connected or internal fuse
blown or rectifier not properly plugged in.
Re-insert rectifier(s) and make sure the
rear connections are good. Confirm that
AC power is available to the rectifier
backplanes. Replace the rectifier module if
the unit is suspected to have failed.
No output current from rectifiers and the
Green LED on each rectifier blinks
occasionally
AC power either <70VAC or >320VAC. An
internal relay will be heard open and close
periodically if the AC voltage is excessive.
Check that the AC supply voltage and
connection arrangement are correct and
match the expected system supply wiring.
Over-temperature alarm or fan failure
alarm present
High ambient temperature.
Fan air intake/exhaust vents are blocked or
a fan is jammed with a foreign object or
excessive dust.
Check the ambient temperature and
improve site cooling if possible.
Check and remove obstructions from the
air vents. Replace the module or remove
and replace the fan assemblies in the
module (requires only that the rectifier lid
be removed)
LVDS will not close
One or more batteries are reverse polarity.
No battery is connected to the battery
distribution module.
Fuse link blown in the battery distribution
module (BDM).
MiniCSU-3 setting for LVDS is “Open”.
MiniCSU-3 setting for LVDS is “Auto” and
the DC bus voltage was < LVDS trip
threshold and has not increased to the float
voltage.
Check battery wiring polarity.
Connect a battery.
Check that the MiniCSU-3 is powered up
even when no rectifier is operational. If
not, service the fuses in the BDM.
Change the MiniCSU LVDS setting to
“Closed” or “Auto”.
Power up the rectifiers and reduce the load
until the bus voltage increases to the float
voltage.
Load or Battery circuit breaker alarm does
not set when the breaker is opened or is
incorrectly alarmed as battery switch
instead of load trip or visa-versa.
No battery or load is connected to the
circuit breaker connection.
Alarm link in BDM is incorrectly configured.
Check load and battery connections to the
BDM and that the alarm links are correctly
configured.
Battery or Ambient temperature sensor
reading is indicated as “Not Available”
Sensor / cable faulty.
Sensor connector reversed.
No sensor installed.
Turn cable connector around and
reconnect.
Replace faulty sensor assembly.
Battery current indicated does not match
independent measurement.
Full-scale current of the DC hall effect
current transducer is incorrectly set and will
result in an error larger than +/- 5% at
more than 50% full-scale current.
Change the setting of the “FS Batt Curr”
value in the Base Menu of MiniCSU-3 to
the correct full-scale value.
Battery current indicates 0A when more
than 5A is flowing in the battery or is
inaccurate at low currents (<5A)
DC hall effect transducer or wiring is faulty.
Current transducer sensitivity is too low for
1A measurement
Service the DC current transducer in the
BDM – check the wiring is intact and still
connected properly, or replace the DC CT
is suspected to be faulty
Revise size of DC CT full-scale value for
the size of the load and battery charging
requirements.
Load current indicates 0A when known to
be >5A
Number of SMRs is incorrectly set too low
or the battery current FS is set too high.
The load current is calculated from the sum
of the SMR currents minus the measured
battery currents
Check that the number of SMRs in the
MiniCSU-3 Base menu matches the actual
number of rectifier modules installed.
Check the Battery DC CT rated full-scale
value is correctly set in the Base menu.
One unit is alarmed as HVSD (high voltage
shutdown) and is latched off.
The unit has developed a fault that causes
it to output a voltage above the HVSD
protection limit and has been supplying
load current while above this voltage limit.
A random event on the DC bus has
occurred that forced a unit into HVSD.
Replacing the rectifier module is
recommended. However, a random event
may have triggered the HVSD and to
determine if the unit has a real fault, the
HVSD latched alarm can be reset using the
“Reset Latched Alarm” function in the
MiniCSU-3 SMR Menu. (If the system
does not have any batteries, cycling the
AC power will have the same effect). If the
unit does not recover by latching off again,
it is faulty.
