Delta OHM DO2003, Manual

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P
RESSURE
M
EASUREMENT
The DO2003 allows to carry out measurements of barometric pressure (PP472 module), as well as
of differential pressure (PP473 S1 … PP473 S8 modules). The pressure modules have to be
connected to input A of the instrument. Press UNIT A to change the unit of measurement of the
displayed instant value. The following units of measurement are available: mbar, Pa, mmH
2
O and
inchW.
B
AROMETRIC
P
RESSURE
M
EASUREMENT
- PP472 M
ODULE
The PP472 module measures the barometric pressure applied to its input in the 600.0…1100.0 mbar
range. Resolution equals 1 mbar over the whole range of measurement.
The fluids in contact with the diaphragm have to be dry and non-corrosive air or gases.
D
IFFERENTIAL
P
RESSURE
M
EASUREMENT
- PP473 M
ODULE
PP473 S1, S2, …, S8 modules measure differential pressures having 10, 20, 50, 100, 200, 500, 1000
and 2000 mbar full scales.
The UNIT A key changes the unit of measurement of the instant value.
Zero Command
In differential probes there might be a slight difference between the two inputs, so that the
instrument, even if the pressure applied to the two inputs of the probe is the same, does not
display the value zero. For this purpose, the instrument is provided with a reset command of the
differential value: leave the inputs of the probe open, so that they can record the same pressure
and press the PROBE ZERO reset key: the instant value is set to zero. The reset can be
performed only if the difference between the two inputs of the module is lower than 5% of the
full scale.