Owner's manual

Operation  2
MultiCal mmHgA/PSIA Pressure Module Manual
Operation
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FUNCTIONS
To ensure safe and accurate operation, please be familiar with the following operations and functions.
!
WARNING: Severe injury or damage can occur through improper use of pressure instruments! Do not exceed recommended pressure limits of
tubing and ttings. Be certain all pressure connections are secured. Never disconnect pressure instrumentation without rst relieving
sy
stem pressure.
!
CAUTION: Never insert any object (other than a 1⁄8" NPT tting) into the inlet ports. The sensor diaphragm is very thin and can be damaged or
destroyed by solid or sharp objects. Clean the sensor with appropriate solvents, only.
T
he internal pressure sensor measures the dierence between atmospheric (barometric) pressure, and the pressure (or vacuum) applied to the pressure port.
The pressure being measured can be either liquid or gaseous, providing it is compatible with the materials listed in the specication section.
PTFE tape should be used with any ttings installed into either of the 1⁄8" female NPT ports. Two ports are provided so that additional tees should not be
required. Plug any unused ports.
MultiCals have been calibrated for use with meters that have 10MΩ input impedance, as do most handheld meters, and some benchtop multimeters. If your
meter has higher or lower input impedance, add 0.1% to the specication of the MultiCal, or refer to the Calibration section of this manual for other methods
of eliminating the error introduced by an impedance mismatch.
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PRESSURE MEASUREMENT
Follow this procedure to correctly use the MultiCal pressure module.
1 Plug the MultiCal directly into the voltage input terminals of the multimeter or with the patch cord set. The patch cord set consists of a 48" cord with double
banana plugs on each end and a double banana jack splice. Plug the splice into the MultiCal and the patch cord into the splice. Plug the other end of the
patch cord into the multimeter. Polarity is marked on the MultiCal and on the patch cord and splice.
2 Set the multimeter to the millivolt (DC) range.
3 Check the battery condition: With the MultiCal still in the OFF position, the multimeter must indicate a minimum reading of 100 mV. Readings less than 100
mV indicate the battery must be replaced. To be sure that your pressure measurements are accurate, always check the battery condition rst, and replace
the battery if necessary.
4 Turn on the MultiCal by sliding the switch to the range you intend to use.
5 Apply pressure to the MultiCal. If the meter reads overrange, change the multimeter range to DC volts (instead of mV).
Note: The decimal place will be for volts. Multiply the reading by 1000. For example, 0.760 V would be 760 mmHgA.