York YVWA, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
99
SECTION 6 - OPERATION
FORM 201.30-ICOM1 (519)
ISSUE DATE: 05/22/2019
6
System Safeties (Faults)
System safeties (faults), as shown in Table 33 on page
99
, are:
• Faults that cause the compressor to be shut down,
if a safety threshold is exceeded for three seconds.
• Recorded in the history buffer along with all unit
data and system operating conditions.
• Auto reset faults where the unit will be allowed to
restart automatically after the fault condition is no
longer present.
If any combination of three faults on the same system
occurs within 90 minutes, that system will be locked
out on the last fault, which requires a manual reset us-
ing the system switches on the keypad and must be
cycled off and on to clear the lockout fault.
TABLE 33 -
SYSTEM SAFETIES (FAULTS)
MESSAGE DESCRIPTION
YYYYYYY CONTROL
VOLTAGE
This fault alerts the user that the system's control voltage is not present, which could be due to
a blown or missing control fuse. This safety will shut down a system if the unit switch input is low
and the other system’s unit input is high. A shutdown will not occur if both systems’ unit switch
inputs are low. This fault occurs immediately, and does not wait for three seconds. This safety will
not cause a lockout. YYYYYYYY will show FAULT to indicate a system is in a FAULT condition,
will restart when the condition clears, and the 120-second anti-recycle timer times out.
YYYYYYY EDUCTOR
CLOG
This fault is designed to detect low flow of oil in the oil return eductor line. This safety will shut
down the unit if the eductor temperature rises above the saturated evaporator temperature more
than the programmed setpoint (5.0 to 50.0°F, default 5.0°F (2.7 °C to 27.7 °C, default 2.7 °C)) for
the programmed eductor safety time (one to 1000 minutes, default 10 minutes). This fault causes
a lockout on the first occurrence. YYYYYYY will show LOCKOUT, and the system will not restart
until the operator clears the fault using the keypad.
YYYYYYY GATE
DRIVER FAULT
Hardware-Initiated Fault - The VSD IGBT gate driver control board monitors the saturation
voltage drop across each IGBT while it commands it gated on. If the IGBT’s saturation voltage
exceeds the prescribed limit, the gate driver shall determine that a short circuit is present, which
causes a system shutdown. Also, if the gate driver board’s power supply voltage falls below its
permissible limit, this same fault is generated. This auto-restart safety will lock out on the third
fault in 90 minutes. The VSD shutdown type is immediate. YYYYYYY will show FAULT to indicate
a system is in a FAULT condition, and will restart when the 120 second anti-recycle timer times
out; or will show LOCKOUT, and the system will not restart until the operator clears the fault
using the keypad.
YYYYYYY HIGH DIFF
OIL PRESSURE
The high differential oil pressure cutout protects the compressor from low oil flow, possibly from
a clogged oil filter. The system will shutdown when its differential oil to discharge pressure rises
above the cutout of 65 psid (4.5 kPa). This safety is ignored for the first 90 seconds of run time.
YYYYYYYY will show FAULT to indicate a system is in a FAULT condition, will restart when the
condition clears, and the 120-second anti-recycle timer times out. If three faults occur within 90
minutes, LOCKOUT will appear, and will not restart until the operator clears the fault using the
keypad.
TABLE 32 - UNIT SAFETIES FAULTS (CONT'D)
MESSAGE DESCRIPTION
UNIT YYYYYYY
VSD LOGIC BOARD
POWER SUPPLY
Hardware-Initiated Fault -
The various DC power supplies which power the logic board are
monitored via hardware located on the logic board. If any power supply falls outside its allowable
limits, the unit initiates a shutdown. This auto-restart safety will lock out on the third fault in 90
minutes. The VSD shutdown type is immediate. YYYYYYY will show FAULT to indicate a system
is in a FAULT condition, and will restart when the 120 second anti-recycle timer times out; or
will show LOCKOUT, and the system will not restart until the operator clears the fault using the
keypad.