McQuay AGS 206A, Руководство по эксплуатации

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26 OM AGSB-5
Automatic Adjusted Limits
The following setpoint ranges will be adjusted based on selected options.
Table 14, Evaporator Leaving Water Temperature Range
Mode Range
Unit Mode = Cool 40 to 60
°
F
Unit Mode = Cool w/Glycol, Ice, Ice w/ Glycol 20 to 60
°
F
Table 15, Evaporator Freeze Temperature Range
Mode Range
Unit Mode = Cool
34 to 42
°
F
Unit Mode = Cool w/Glycol, Ice, Ice w/ Glycol 15 to 42
°
F
Table 16, Low Evaporator Pressure Inhibit
Mode Range
Unit Mode = Cool 30 to 45 Psig
Unit Mode = Cool w/Glycol, Ice w/ Glycol 15 to 45 Psig
Table 17, Low Evaporator Pressure Unload
Mode Range
Unit Mode = Cool 28 to 45 Psig
Unit Mode = Cool w/Glycol, Ice w/ Glycol 15 to 45 Psig
Table 18, Low Ambient Lockout Temperature Range
Fan VFD Range
Fan VFD = N
35– 60
°
F
Fan VFD = Y 0 – 60
°
F
Unit Enable
Enabling and disabling the chiller is controlled by the Unit Enable Setpoint with options of
OFF and ON. The Unit OFF input (unit On/Off switch), field installed Remote stop switch,
keypad entry, or BAS request can alter this setpoint providing the correct control source
setpoint is selected. The Control Source Setpoint determines which sources can change the
Unit Enable Setpoint with options of SWITCHES, KEYPAD, or NETWORK.
Changing the Unit Enable Setpoint can be accomplished according to Table 19 on page 27.
NOTE: An “x” indicates that the value is ignored.
Set Unit Setpoints Screen #1 (shown below) shows three fields “Enable”, “Mode” and
“Source.”
Unit Setpoints
SET UNIT SPs (1)
Enable=On
Mode= COOL
Source = KEYPAD
The Enable field is for use with Source = Keypad only, to enable and disable the chiller
through the key pad, ignoring any other control inputs including unit and pumpdown
switches and BAS controls.