McQuay WSC Operating Manual page 25

4. Press the appropriate numbers in the numeric keyboard to enter the password. There is a small
delay between pressing the keypad and recording the entry. Be sure that an asterisk appears in
the window before pressing the next number. Press ENTER to return to the SETPOINT
screen. The password will remain open for 15 minute after initiation and does not need to be
re-entered during this period.
5. Press CHANGE again. The right side of the screen will turn blue (inactive).
6. The numeric keypad and action buttons in the lower left-hand corner of the screen will be
activated (the background will turn green). Setpoints with numeric values can be changed in
two ways:
•
•
7. Additional setpoints can be changed by selecting another setpoint on the screen or by selecting
an entirely new group of setpoints.
Explanation of Setpoints
Each of the seven setpoint group of screens are detailed in the following section. In many cases
the setpoint content is obvious and no explanation is included.
1. TIMERS, for setting timers such as start-to-start, prelube, postlube, etc.
2. ALARMS, for setting the limit and shutdown alarms.
3. VALVE, sets the parameters for operation of an optional field installed tower bypass valve.
4. TOWER, selects the method of controlling the cooling tower and sets the parameters for fan
staging/VFD.
5. MOTOR, selects motor related setpoints such as amp limits, VFD settings, etc. Also has
maximum and minimum rate of change of chilled water temperature.
6. MODES, selects various modes of operation such as control source, multiple compressor
staging, pump staging, BAS protocol, etc.
7. WATER, leaving water temperature setpoint, start and stop delta-T, resets, etc.
OM Centrif Micro ΙΙ-5
Select the desired value by pressing the numbered buttons. Press ENTER to enter the
value or CANCEL to cancel the transaction.
Press the UP or DOWN button to increase or decrease the value displayed. Press ENTER
to enter the value or CANCEL to cancel the transaction.
Some setpoints are text rather than numeric values. For example, LWT Reset Type can be
"None" or "4-20 ma". The selection can be made by toggling between choices using the
UP or Down button. If dashed lines appear in the setpoint window, it indicates that you
have toggled too far and need to reverse direction. Press ENTER to enter the choice or
CANCEL to cancel the transaction.
Once CHANGE is selected, the CANCEL or ENTER buttons must be pressed before
another setpoint can be selected.
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