Sper Scientific 840085 Manometer - 2 PSI User Manual
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Press HOLD to freeze the pressure reading (Pg 6, Fig E). Press the
HOLD
button again to release this setting.
Press the DIF button and "DIF" appears near the top of the LCD and the
display indicates the relative zero. Only the amount of the pressure
change will be indicated (Pg 6, Fig F). Press the DIF button again and
the unit returns to the normal mode.
Press the UNIT button repeatedly to cycle through the units of measure
indicated below the LCD display (Pg 6, Fig G and H)
Press the Backlight button and the LCD illuminates for approx. 30
seconds then turns off automatically.
Note: Differential Pressure is a measure of the difference between two
pressures, for example, use differential pressure sensor to measure gauge
pressure by leaving one process connection open to atmosphere and
connecting the second sensor port to your system.
3-B. Zero Setting
Do not apply pressure to the connector and disconnect the tube. Failure to
follow this procedure can cause damage and void the warranty. To set the
display to zero, turn the unit on and press the HOLD button for 2 seconds.
The LCD displays "o o o o" one at a time, from left to right. Next, the LCD
clears and displays a zero setting (Pg 6, Fig I).
3-C. Calibration
The meter is factory calibrated. Annual recalibration at a qualified meter
calibration facility is recommended. The following information is for the
calibration technician:
Use a standard manometer calibrator to calibrate this unit. Refer to the
Calibration Point Reference chart on page 7. The examples are for model
number 840083, with a pressure range from 0 to +100 PSI (positive pressure)
or from 0 to -100 PSI (Negative pressure). The meter must be attached to a
pressure source between 75.0 and 85.0.
Turn ON the unit (Make sure the manometer is in PSI mode)
Hold button for zero calibration.
Set the calibrator to 80.00 PSI.
Check manometer readings if it is not within specs (enter positive calibra-
tion mode by pressing POWER and REC buttons simultaneously).
80.00 PSI should be displayed on the LCD of the manometer and the
calibrator should have the same value.
Press the REC button to save the calibration point.
Press the UNIT button to return to normal mode and check readings
again compared the calibrator.
Turn OFF the manometer.