VYPER
™
VARIABLE SPEED DRIVE
MAINTENANCE
100-210 IOM (
JUL
09)
Page 65
Fault 44: Vyper
™
Low Converter Heat Sink Temperature
Message
Quantum: “Fault 44”
Quantum LX: “VSD Low Converter Heatsink Temp Fault”
The phase bank assembly heatsink temperature and the
inverter module baseplate temperature are compared to a
lower limit of 37°F (3°C). If the inverter baseplate tempera-
ture or the converter heat sink temperature falls below 37°F
(3°C), the message displayed is Fault 44. In addition, if both
temperatures fall below the 37°F (3°C) limit, the unit will trip
and the fan(s) and water pump will be energized. This feature
provides service personnel with the ability to run the water
pump while filling the cooling system (by pulling VSD logic
board plug P2).
A thermistor sensor is located behind the last SCR/Diode
block on the copper chill plate of the Vyper
™
Power Unit. If at
anytime this thermistor detects a temperature of 37°F (3°C)
or lower a shutdown will occur. Sometimes a thermistor wire
can be pinched against the enclosure.
In most cases, the problem will actually be an open thermis-
tor or broken wiring to the thermistor. The normal thermistor
resistance is 10K ohms at 77°F (25°C). Check the circuit for
continuity at Vyper
™
Logic board plug J2. Also make certain
one side of the circuit is not shorted to the cabinet.
Fault 45: Vyper Low Current Imbalance
Message
Quantum: “Fault 45”
Quantum LX: “VSD Current Imbalance Fault”
When the average of the three output phase currents (see
section 10.1) exceeds 80% of the 100% Job FLA (see sec-
tion 13.1.6), the % Output Current Imbalance is calculated
using the following equation:
(I
a
-I
ave
) + (I
b
-I
ave
) + (I
c
-I
ave
)
X 100 =
(I
a
+ I
b
+ I
c
)
2(I
ave
)
3
If the % Imbalance exceeds 30% continuously for 45 seconds,
the unit trips and the Quantum
™
LX panel displays Fault 45.
The imbalance fault is released when the average of the three
output phase currents drops below 80% FLA.
Fault 46: Vyper Precharge – DC Bus Voltage Imbalance
Message
Quantum: “Fault 46”
Quantum LX: “VSD Precharge DC Bus Voltage Imbalance”
The half DC link voltage magnitude will remain within
± 88VDC of the total DC link voltage divided by two during
the precharge interval for both the 60 and 50 Hz VSD’s. If
not, the Quantum
™
LX panel displays Fault 46.
The definition for this fault is identical to “VSD - DC Bus Volt-
age Imbalance”, except that the fault has occurred during the
precharge period which begins during prelube.
Fault 47: Vyper Precharge – Low DC Bus Voltage 2
Message
Quantum: “Fault 47”
Quantum LX: “VSD Precharge Low DC Bus Voltage 2”
The DC link voltage will reach at least 500 VDC within 20
seconds after the precharge signal has been asserted on
the 60 Hz VSD and at least 414 VDC within 20 seconds on
the 50 Hz VSD. If not, the Quantum
™
LX panel will display
Fault 47.
The unit is shut down and this message is generated if this
condition is not met. If this shutdown occurs, measure the
bus voltage at the laminated bus structure, check the wiring
between the Vyper
™
Logic board and Quantum
™
LX Vyper
™
trigger board, and the input SCR’s, and the DC bus isolator
board and the Vyper
™
Logic board.
Fault 48: Vyper Precharge – Low DC Bus Voltage 1
Message
Quantum: “Fault 48”
Quantum LX: “VSD Precharge Low DC Bus Voltage 1”
The DC Bus voltage must be equal to or greater than 50 VDC
for 60 Hz (41 VDC for 50 HZ) four (4) seconds after precharge
has begun. The unit is shut down and this message is gener-
ated if this condition is not met. If this shutdown occurs, mea-
sure the bus voltage at the laminated bus structure, check
the wiring between the Vyper
™
Logic board and Quantum
™
LX
Vyper
™
trigger board, and the input SCR’s, and the DC bus
isolator board and the Vyper
™
Logic board.
Fault 50: Harmonic Filter High DC Bus Voltage
Message
Quantum: “Fault 50”
Quantum LX: “Harmonic Filter High DC Bus Voltage Fault”
The harmonic filter’s DC link voltage is continuously moni-
tored and if the level exceeds a range of 822 to 900 VDC, a
Filter Bus Over-Voltage shutdown is initiated. The harmonic
filter has its own DC bus as part of the filter power module
and this DC Link is not connected in any way with the drive’s
DC Link. If this shutdown occurs, check the level of the 460
VAC applied to the drive. The specified voltage range is 414
to 508. If the incoming voltage exceeds 508 VAC, reduce
the voltage to within the specified limits. The cause of this
message will typically be high line voltage or a surge on the
utility supply.
Fault 51: Harmonic Filter High Phase C Current
Message
Quantum: “Fault 51”
Quantum LX: “Harmonic Filter High Phase C Current Fault”
The three output lines from the 519 filter to the three-phase
output inductor are monitored via two Hall effect DC current
transformers (DCCT1 and DCCT2) within the drive. The third
phase is derived using the equation I
f2
= -I
f1
+I
f3
.
The unit’s three phases of instantaneous output current are
compared to a prescribed limit contained in hardware. If
any one of these three signals exceeds the prescribed limit,
the filter is stopped by inhibiting the Current Regulator Run
signal for five to six input line voltage. If any one of the three
signals exceeds the prescribed limit three times in 60 line
cycles, the unit will trip and the Quantum
™
LX panel displays
Fault 51. The preset limits are as follows:
• 700/572 HP = 782 Amps
• 912/752 HP = 1225 Amps
If this shutdown occurs and the Vyper
™
auto-restarts, con-
tinuing to run properly with the filter operating, the like cause
is the filter tripped on overcurrent due to a sag or surge in
the voltage feeding the chiller. If this message reoccurs,
preventing the unit from restarting, check the filter power
