DH Instruments PPCK PLUS, Operation And Maintenance Manual

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PPCK+™ Operation and Maintenance Manual
©2001 DH Instruments, Inc .
Page 32
Select the desired reference temperature for water density using the [
←
] or [
→
] key to
move the cursor. Pressing [ENTER] returns to the main run screen with inWa based on
water density at the selected reference temperature as the pressure unit. The current
inWa reference temperature can be viewed by observing the position of the cursor in the
reference temperature screen.
There are two possible default pressure unit screens (one US and one SI) depending on
whether the PPCK+ has been factory set as US or SI. Whether the PPCK+ is set up as US
or SI is indicated by the right two characters on the top line of the PPCK+ introduction
screen which can be viewed by pressing [ESCAPE] from the main run screen or when
powering up PPCK+. For a US PPCK+ the default units are <1psi>, <2MPa>, <3kPa>,
<4bar>, <5kcm2>. For an SI PPCK+, the default units are: <1MPa>, <2kPa>, <3bar>,
<4psi>, <5kcm2>.
No reference temperature selection is necessary for the unit mmWa as the only reference
temperature commonly used for mmWa is 4 ºC.
The pressure measurement unit selected is range specific. When in a given range, all
functions and setting values are represented in the current measurement unit for
that range. However, certain internal and/or metrological functions (e.g., RPT calibration
coefficients) are always represented in Pa regardless of the current range unit.
See Section 7.2.1 for tables of the conversion factors used by PPCK+.
The choice of six units available under the UNIT function can be modified from a wider
selection by the user (see Section 3.4.3). The units available under the UNIT function can
be reset to default by pressing [SPECIAL] and selecting <4Internal>, <5Reset>, <2units>
(see Section 3.4.4.5).
3.2.3 [CONTROL]

PURPOSE
To set the automated pressure control mode for the active range and activate default
control parameters.