York MILLENIUM 1100-46D, Руководство по эксплуатации

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JOHNSON CONTROLS
18
FORM 160.00-O1 (1020)
can reach 158°F. If this message does occur, make
certain you have an adequate level of coolant, check
to be sure the cooling pump is operating when the unit
is running, and check the strainer in the primary of the
heat exchanger for clogs and silt.
Message:
HIGH CONVERTER HEATSINK TEMP
Reference “High Phase A (B,C) Heatsink Temp” above.
This shutdown requires a manual reset via the Reset
push-button on the VSD logic board.
Message: 105% MOTOR CURRENT OVERLOAD
This shutdown is generated by the VSD logic board
and it indicates that a motor overload has occurred.
The shutdown is generated when the VSD logic board
has detected that at least one of the three output phase
currents has exceeded 105% of the programmed 100%
job full load amps (FLA) value. The 100% job FLA
setpoint may be viewed by pressing the “Options” key.
This shutdown requires a manual reset via the Reset
push-button on the VSD logic board.
Message:
BUS OVER-VOLTAGE FAULT
The VSD’s DC link voltage is continuously monitored
and if the level exceeds 745 VDC, a Bus Over-Voltage
shutdown is initiated. If this shutdown occurs, it will be
necessary to look at the level of the 460 VAC applied to
the drive. 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 within the specified limits.
Message:
MAIN BOARD POWER SUPPLY
This shutdown is generated by the VSD logic board
and it indicates that the low voltage power supplies for
the logic boards have dropped below their allowable
operating limits. The power supplies for the logic boards
are derived from the secondary of the 120 to 24 VAC
transformer (Fig. 2) which in turn is derived from the 480
to 120 VAC control transformer (Fig. 1). This message
usually means that power to the VSD was removed.
Message:
LOW DC BUS VOLTAGE FLT
If the DC link drops below 500 VDC (or 414 VDC for 50
HZ), the drive will initiate a system shutdown. A common
cause for this shutdown is a severe sag in the incoming
power to the drive. Monitor the incoming three phase
AC line for severe sags and also monitor the DC link
with a digital meter.
Message:
BUS VOLTAGE IMBALANCE FAULT
The DC link is filtered by many large, electrolytic capaci -
tors which are rated for 450 VDC. These capacitors are
wired in series to achieve a 900 VDC capability for the
DC link. It is important that the voltage be shared equally
from the junction of the center or series capacitor con-
nection, to the negative bus and to the positive bus. This
center point should be approximately ½ of the total DC
link voltage. Most actual bus voltage imbalance conditions
are caused by a shorted capacitor, or a leaky or shorted
IGBT transistor in an output phase bank assembly. This
usually indicates the VSD requires service.
Message:
HIGH AMBIENT TEMPERATURE FLT
The ambient temperature monitored is actually the
temperature detected by a component mounted on the
VSD logic board. The high ambient trip threshold is set
for 140°F. Some potential causes for this shutdown are:
internal VSD fan failure, VSD water pump failure or an
entering condenser water temperature which exceeds
the allowable limit for the job. Additional causes for the
shutdown include:
• Plugged Strainer – The standard 1.5” Y-Strainer con-
tains a woven wire mesh element with 20 stainless-
steel wires per inch. This has been found to work
adequately in most applications. Some users may
have very dirty condenser water which can cause the
strainer to plug. Locations with special conditions
may want to consider a dual strainer arrangement
with quarter turn valves, to permit cleaning of one
strainer with the unit still on-line.
• Plugged Heat-Exchanger – In cases where the
strainer plugs frequently, the heat-exchanger
eventually may plug or become restricted to the
point of reduced flow. At this point we suggest you
back-flush the heat-exchanger by reversing the two
rubber hoses which supply condenser water to/from
the heat-exchanger. If the rust or sludge cannot be
back-flushed, you may need to replace the heat-
exchanger.
• Low Condenser Flow – The VSD system requires
8 feet of pressure drop across the heat exchanger
to maintain adequate GPM. If the pressure drop is
less than 8 feet, it will be necessary to correct the
flow problem, or add a booster pump as is applied
on retrofit chillers.
Message:
INVALID CURRENT SCALE FAULT
Since the part number of the logic board is the same
on all horsepower sizes, jumpers tell the logic board
the size of the VSD being employed in order to properly
scale the output current. If the jumper configuration is
found by the logic to be invalid, the system will be shut
down and the above message will be generated. The
proper jumper configuration is shown on the wiring label
for the VSD.