YORK INTERNATIONAL
14
LD06834
FIG. 22 –EXTERNAL SIGNAL FOR REFRIGERATION
UNIT FAILURE (NOTE 6)
FIG. 22 – EXTERNAL SIGNAL FOR REFRIGERATION
UNIT FAILURE
When the Safety Shutdown Contacts (see Fig. 3) are not
connected to an Energy Management System they may
be employed to energize a local or remote safety alarm (by
others). When the normally open Safety Shutdown Con-
tacts close, the alarm will indicate shutdown of the unit.
The cause of shutdown will be one or more of the follow-
ing safety controls: low oil pressure; high oil pressure; high
condenser pressure; low evaporator pressure; high oil tem-
perature; high discharge temperature; auxiliary safety;
power failure when the “Auto Restart After Power Fail-
ure” Dip Switch on the Microboard (Fig. 21) is in the OFF
position (SW1, position 5 = OFF), which implies that the
chiller requires “Manual Restart After Failure”.
SETUP screen. Press the “English/Metric
Units” key to select the desired units. The data
field will toggle between English and Metric with
each press of the “ or ” key. For English
Units, the temperature display is in degree Fahren-
heit (°F), and absolute pressure is in pounds per
square inch (psia). For Metric Units, temperature
is in degrees Celsius (°C), and pressure in
KiloPascals (kPa).
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On Solid State Starter units only, when the Current
Imbalance option is selected via the Solid State Starter
screen, three phase current imbalance protection is pro-
vided. A safety shutdown occurs (following a 45 sec-
ond by-pass at startup) whenever the % FLA readout
exceeds 80% for 45 seconds continuously and the %
imbalance is > 30%. When all safety controls are satis-
fied, and the OptiView Control Center COMPRESSOR
switch has been manually “Reset” (de-energizing
alarm) and returned to the RUN position (“1”), the unit
may be restarted, if panel is in “Remote” mode, via
the Remote Start contacts (Fig. 6); or, if panel is in “lo-
cal” mode by momentarily pressing the keypad com-
pressor switch to the START (“
”) position.
If the unit was shut down because of
Cycling Shutdown Contacts (see Fig.
2) the alarm will not be energized, but
the unit will have been shut down. A
closure of the safety alarm contacts
means that an operator must manu-
ally reset and restart the unit.
When the Safety Shutdown contacts close, the OptiView
Control Center will display the following message:
“SAFETY SHUTDOWN – MANUAL RESTART”,
and cause of shutdown.
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LD06836
FIG. 23 – RUN CONTACTS / REMOTE RUN LIGHT
AND SHUTDOWN INDICATOR PLUS EMS