VYPER
™
VARIABLE SPEED DRIVE
MAINTENANCE
100-210 IOM (
JUL
09)
Page 62
Fault 18: High Phase B Instantaneous Current
Message
Quantum: “Fault 18”
Quantum LX: “VSD High Phase B Instantaneous Current”
Same comments as Fault 17 except applying to Phase B
Instantaneous Current
Fault 19: High Phase C Instantaneous Current
Message
Quantum: “Fault 19”
Quantum LX: “VSD High Phase C Instantaneous Current”
Same comments as Fault 17 except applying to Phase C
Instantaneous Current.
Fault 21: Vyper Phase A Gate Driver
Message
Quantum: “Fault 21”
Quantum LX: “VSD Phase A Gate Driver Fault”
The unit’s phase bank assembly shall contain one IGBT
gate driver control board. This board monitors the satura-
tion voltage drop across each IGBT while gated on. If the
IGBT’s saturation voltage exceeds the prescribed limit, the
gate driver will make the determination that a short circuit is
present. This will cause the unit to trip and the Quantum
™
LX
Panel displays Fault 21. If the driver board’s power supply
voltage falls below the permissible limit, this same message
is generated.
A second level of overcurrent protection exists on the Vyper
™
gate driver board. The collector-to-emitter voltage of each
IGBT is checked continuously while the device is being
turned on. This is also called the collector-to-emitter satura-
tion voltage. If the voltage across the IGBT is greater than a
set threshold, the IGBT is turned off and a shutdown pulse
is sent to the Vyper
™
Logic board shutting down the entire
system. To diagnose the problem, first check the LED’s on
the gate driver board of the Vyper
™
power unit. Usually one
of the six LED’s will be out. This clearly points to a bad gate
driver, and requires replacement of the Vyper
™
power mod-
ule. If all LED’s are lit, and the problem repeatedly occurs
in one phase, swap all three pole cables at the logic board
J8, J9, and J10. Plug J8 into J9, J9 into J10, and J10 into
J8. If the display now reports a trip in a different phase, the
problem is either in the Vyper
™
power module or gate driver
board, or in the cable that feeds the gate driver board from
the Vyper
™
Logic board. The fault could also be cause by a
problem in the drive line. Ensure that the compressor is free
to rotate. If the display continues to report a gate driver FLT
in the same phase, even with cables swapped, the problem is
in the Vyper
™
Logic board. Once troubleshooting is finished,
be sure to put all of the cables back into the original mating
connectors. Note that a gate driver fault can be initiated when
the Vyper
™
is not running because a power supply has failed
on the gate driver board.
Verify that the LRA value of the motor does not exceed the
LRA value rating of the drive.
Fault 22: Vyper Phase B Gate Driver
Message
Quantum: “Fault 22”
Quantum LX: “VSD Phase B Gate Driver Fault”
Same comments as Fault 21 except applying to Phase B
Gate Driver.
Fault 23: Vyper Phase C Gate Driver
Message
Quantum: “Fault 23”
Quantum LX: “VSD Phase C Gate Driver Fault”
Same comments as Fault 21 except applying to Phase C
Gate Driver.
Fault 24: Vyper Single Phase Input Power
Message
Quantum: “Fault 24”
Quantum LX: “VSD Single Phase Input Power Fault”
The Vyper’s SCR Trigger Control board contains circuitry that
checks the three-phase mains for the presence of all three
line voltages. If all line voltages are not present, the unit will
trip and the Quantum
™
LX Panel will display the message
Fault 24.
This shutdown is generated by the SCR Trigger board and
relayed to the Vyper
™
Logic board to initiate a system shut-
down. The single-phase control uses circuitry to detect the
loss of any one of the three input phases. The trigger board
will detect the loss of a phase within one half line cycle of the
phase loss. An LED on the SCR Trigger board will indicate
that the board is detecting the fault, and not a wiring problem
between the trigger board and the Vyper
™
Logic board. This
message is also displayed every time power to the Vyper
™
is
restored or if the input power dips to a very low level. Usually
this indicates an open disconnect switch or one of the input
fuses (F1-F3) to the trigger board has failed.
Fault 27: Vyper 105% Motor Current Overload
Message
Quantum: “Fault 27”
Quantum LX: “VSD 105% Motor Current Overload Fault”
The Vyper
™
Logic Board generates this shutdown by read-
ing the current from the 3 output current transformers. The
shutdown is generated when the Vyper
™
Logic board has
detected that the highest of the three output phase currents
has exceeded 105% of the programmed 100% full load amps
(FLA) value for more than 7 seconds. If this is detected,
the unit will trip and the Quantum
™
LX panel will display the
fault message. The 100% FLA setpoint is determined by
adjustment of the FLA trim pot on the logic board. This fault
will require clearing using the manual reset button located
on the Logic board. The overload timer resides in the Field
Programmable Gate Array which is programmed by the serial
E^^2 PROM on unit power-up.
Fault 28: Vyper High DC Current Bus Voltage
Message
Quantum: “Fault 28”
Quantum LX: “Vyper High DC Current Bus Voltage”
The DC link overvoltage trip level is determined by hardware
on the logic board and is designed to trip the unit at 745 +/-
17 VDC for both 60 and 50 Hz VSD’s. If the DC bus current
exceeds this level, the unit will trip and the Quantum
™
LX
Panel will display the message Fault 28.
If this shutdown occurs, it will be necessary to look at the level
of the 460 VAC applied to the Vyper
™
. The specified voltage
range is 414 to 508. If the incoming voltage is in excess of
508, steps should be taken to reduce the voltage to within
the specified limits.
