Table 4: Cycling shutdown message
Message
Description
VSD - Precharge - Low DC Bus Voltage
PRECHARGE LOW VOLTAGE FAULT
This fault has two different timing events. First, the DC Bus voltage must be equal
to or greater than 50 VDC for 460 VAC input voltage, 41 VDC for 380, 400 and 415
VAC input voltage, or 60 VDC for 575 VAC input voltage, 4 seconds after pre-charge
has begun. Second, the DC Bus voltage must be equal to or greater than 500 VDC
for 460 VAC input voltage, 414 VDC for 380, 400 and 415 VAC input voltage or 600
VDC for 575 VAC input voltage, 20 seconds after pre-charge has begun.
VSD - Run Signal
RUN RELAY FAULT
Two run signals are generated by the Control Center, one via hardware and the
second via the communications link. Upon receipt of either of the two run signals
by the OSCD logic board, a 5-second timer will begin. If the missing run signal is
not received within the 5-second window the OSCD logic board will shut down and
the Control Center will display the shutdown message.
VSD - Serial Communications
SERIAL RECEIVE FAULT
This message is generated when communications between the microboard
and the ACC board, or the ACC board and OSCD logic board is disrupted for a
least 22 seconds. If the optional Harmonic Filter is installed then the fault can
be generated when the communications between the OSCD logic board and the
Harmonic Filter logic board, or the Harmonic Filter logic board and the ACC board
is disrupted.
VSD - Single Phase Input Power
SINGLE PHASE POWER SUPPLY
This shutdown is generated by the SCR Trigger board and relayed to the OSCD
logic board to initiate a system shutdown. 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 OSCD logic board. This
message is also displayed every time power to the OSCD is restored, or if the input
power dips to a very low level. Usually it indicates that someone has opened the
circuit breaker.
VSD - Stop Contacts Open
INVERTER INITIATED STOP FAULT
Whenever the OSCD initiates a fault, it first opens the fault relay on the OSCD logic
board. When the relay opens a message is sent to the ACC board, detailing the
cause of the fault. If this circuit ever opens without receiving an accompanying
cause for the fault over the communication link (within 11 communication tries,
ap- proximately 22 seconds) this message will be displayed. This fault may be
replaced with a Serial Communications fault if the serial link has failed.
The three phases of RMS filter current are measured by the output DCCTs’. This
information is sent to the harmonic filter logic board. If any one phase of filter cur-
rent exceeds a threshold for 40 seconds a shutdown will occur. Refer to the chart
below for the shutdown threshold value.
Drive hp rating
Threshold shutdown value
270, 292, 351
128 Amps
424
138 Amps
385, 419, 503
176 Amps
608 (575 VAC)
190 Amps
608 (400 VAC), 658, 704, 790
278 Amps
Harmonic Filter - 110 % Input Current
Overload
FLTR OVERLOAD FLT
868, 882, 914, 917, 948, 1055
385 Amps
Harmonic Filter - DC Bus Voltage
Imbalance
FLTR BUS V IMBALANCE FLT
The DC link is filtered by many large capacitors. These capacitors are connected
in series to achieve a higher DC link voltage then can be supported by a signal
capacitor. It is important that the voltage is shared equally between the two sets
of series capacitors. Each set of capacitors must share approximately 1/2 of the
total DC link voltage. The harmonic filter logic board then measures the voltage of
the 2 sets of the bus capacitors. If at anytime while the harmonic filter is running
that the difference in the voltage between the 2 sets of capacitors is greater
than 50 VDC (for 380 through 460 VAC input voltage) 65 VDC (for 575 VAC input
voltage), then a shutdown will occur.
39
Liquid-Cooled OptiSpeed Compressor Speed Drive
