Dunham-Bush ACXi 165-5SP-LN, Installation, Operation And Maintenance Manual

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4.0 ELECTRICAL
4. a.) If you want to change setpoint A,
press in the desired new value and
press ENTER. if the new value is
within allowable limits, it will be
stored in memory. The cursor will
then move to setpoint B.
b.) If you do not want to change
setpoint A, press ENTER.
5. Repeat 4, for Setpoint B.
4.4.6 TO CALIBRATE TEMPERATURE
AND PRESSURE SENSORS
1. You must be authorized and in the
PROG mode. See Section 4.4.4.
2. Display the analog sensor to be
calibrated on the top line of the
display.
3. Press ENTER to show ZERO
CALIBRATION value.
4. Use an accurate gauge to measure the
analog value when it is stable and near
design conditions.
5. Determine the revised zero calibration
required as follows: Meter Reading -
AI D Zero Calibration = New
Zero Calibration. The new zero
calibration must be rounded to the
nearest whole number.
6. Press ENTER to place the cursor on
the zero calibration value.
7. Enter the new value from 5. Negative
values are entered by pressing
LOWER FU/- before the
number.
8. Press ENTER to store the revised zero
calibration.
For example, if a suction pressure
gauge shows 58 psig and the computer
displays 60.3 psig with a zero
calibration of -1, then new calibration
would be 58 - 60.3 + (-1)= -3.3(-3). So
the zero calibration should be changed
to -3. Then the computer will display
58.3.
4.4.7 TO SET DATE AND TIME
1. You must be authorized. See Section
4.4.4.
2. Select DATE & TIME SET on the
main menu. Press ENTER to display
current date and time.
3. Press ENTER key to move cursor to
each date/time item.
4. As each item flashes, use the number
keys to enter revised data if necessary.
5. Press ENTER to continue. The last
ENTER will store the new date and
time.
WARNING:
Setting the clock will cause
a system reset. The entire unit will shut
down and start over again. If the change
was started inadvertently, press MENU
key before completing the change.
4.4.8 TO DISPLAY DATA WITHOUT
ACCESSING MENU
1. Press LOWER FUNCTION.
2. Press function desired (blue sub-script)
3. Press item number to be displayed.
4. Press ENTER.
EX: To display analog input #5, press
LOWER FUNCTION, ANALOG
INPUT, 5, ENTER.
4.4.9 UNIT SCHEDULE OF
OPERATION
If a seven day time schedule of unit
operation is desired, the internal real time
clock of the microcomputer can be used.
When the SCHEDULE control point is
ON, the compressor is allowed to operate.
The following procedure is used to
modify the operating schedule.
1. Perform the authorization procedure
(See Section 4.4.4).
2. Press MENU key.
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