York YCAQ10, Руководство пользователя

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FORM 150.40-NM20
43
YORK INTERNATIONAL
rent Board which rectifies and filters the signal to vari-
able DC voltage (analog). This analog level is then fed
to the Analog Input Board allowing the Micro Logic Board
to monitor motor current.
SYSTEM SAFETIES
SHUTDOWN SAFETY CONTROLS
A. These software controls in the Micro Board auto-
matically reset and allow restart of the system with-
out operator intervention (auto-restart) when the
condition causing the shutdown clears. After the
condition causing the shutdown clears, the unit will
restart in a minimum of 2 minutes, or a maximum of
10 minutes, depending upon the remaining time on
the anti-recycle timer. Restart will occur only if cool-
ing demand is present. An “F” code will be displayed
for LAT* and HAT* shutdowns. Otherwise, no code
will be displayed other than one indicating the
anti-recycle timer(s) is in effect.
1. Power Failure: After power has been restored, the
unit will automatically restart after a 2 minute time
delay. System acts as it does any time power is ap-
plied. Restart is dependent on cooling demand after
the 2 minute start-up timer has completed its cycle.
2. Flow Switch/Remote Cycling Device: The Micro
Board monitors the closure of the Flow Switch Con-
tacts. Upon opening of the contacts, the unit will shut
down and will remain off until the contacts close.
Remote devices are wired in series with the Flow
Switch and can be used to start and stop the unit.
Anytime the contacts open, an “A” Code will appear
on the display indicating a Flow Switch problem or
an EMS/BAS/Time Clock stop.
3. Low Pressure Cutout: Compressor suction pres-
sure cutout is a factory adjustable setpoint (R26) on
the Analog Board. It will be factory set at 44 PSIG. If
Glycol or Brine is utilized, then the cutout can be
varied according to mixture. Suction pressure must
be 80% cutout after 30 sec. of running and must
remain above cutout after 4 minutes of operation.
The system will restart after an LP shutdown pro-
vided the anti-recycle timer has timed out and a mini-
mum 2 minute delay before restart has passed.
NOTE: The system will be locked out on a Fault if cycled
on LP on 3 successive starts. See LEP (Low
Evaporator Pressure Cutout) in the MANUAL
RESET SAFETY CONTROLS section.
4. Low Ambient Temperature Cutout (LAT*): Unit is
locked out when the ambient temperature is below
0° to 50°F (Adjustable on Analog Board resistor
R24). This is factory set at 35°F. Upon a rise in tem-
perature above setpoint, the unit will restart provided
the antirecycle timer has timed out and a minimum
2-minute delay has passed. An “F 10” code will be
displayed while the temperature is low and both sys-
tems will be shut down. The F will disappear when
temp. rises above cut-out.
5. High Ambient Temperature Cutout (HAT*): Unit
locks out when the ambient temperature is above
130°F. Upon a decrease in temperature below 130°F,
the unit will restart providing the anti-recycle timer has
timed out and a minimum 2-minute delay has passed.
An “F9” code will be displayed while the temperature
is high and both systems will be shut down. The F will
disappear when temp. drops below cut-out.
MANUAL RESET SAFETY CONTROLS
A. The system will shut down instantly when a Manual
Reset Fault is sensed, but it will allow automatic re-
start until it sees a total of any 3 Faults in a 90-minute
period.**A 90-minute counter is started as soon as
the 1st Fault occurs. If 2 more faults do not occur in
the next 90 minutes, the counter is reset to “0”.
After a fault, restart cannot be expected until the
anti-recycle timers time out. No display (“F” Code)
will be indicated during the first two faults except for
a letter code telling the operator the anti-recycle timer
is in effect.
After 3 faults, an “F” code will be displayed and the
system will not restart. The fault can be cleared and
the compressor restarted by placing the System Off/
On Switch to the OFF position. However another
fault will shut down the system and an “F” code will
be displayed. The system will continue to shut down
after restart on every Fault with an “F” Code until
the problem system runs without faulting for 90 min-
utes or until power is cycled. Recycling power will
reset the counter to “0”.
1. HP: Unit shuts down when the discharge pressure
exceeds the pressure cutout setpoint of 395 PSI set
in software. An F4 (Sys 1) or an F8 (Sys 2) will ap-
pear for this safety. See also 6) FS (Fault Stop) for
external HP safety.
2. Power Fault: Analog signals are provided to the Micro-
Board by the Motor Current Boards (MCB) which get
info. from 6 current transformers (C.T.’s; 3 per sys-
tem). A signal of 4VDC = 100% FLA Current. The af-
fected system shuts down if the signal is < 1.2VDC
(<30% FLA) or >4.6 VDC (> 115% FLA) when Run
Time > 4 sec. This protection assures that both
contactors are energized, all C.T.s are connected and
operating, and that the motor is not drawing excessive
current. An F1 (Sys 1) or an F5 (Sys 2) will be dis-
played for this safety. Note: See also 6) FS (Fault Stop).
3. Oil Pressure Cutout: An analog signal is provided
(YCHA120, 150, 175, & 200)
* These controls are not furnished as part of the standard unit. A 10K ohm resistor is used in place of them.
** This does not apply to item #4 (LWT Freeze Safety). A fault on the LWT Freeze Safety will cause the system to shut down and lock out
on a single fault.