Druck PACE1000, Инструкция по эксплуатации

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Copyright 2010 Baker Hughes Company.
English–PACE Indicators Instruction Manual | 35
Installation Notes
6. Reference
6.1 Installation Notes
The PACE1000 pressure indicator requires a set of connections with the exception of the
reference connection, this provides a reference to atmosphere for gauge sensors and barometric
sensors.
The gas density and type does not affect the accuracy of pressure measurement, assuming that
the UUT is at the same level (height) as the indicator or gas head correction is accurately set.
6.2 Reference Port
The reference port provides the negative pressure to the gauge sensor and to the barometric
reference (option). Gauge sensors use this port identified as “REF”. For gauge sensors (without
a barometric reference) small pressures can be applied. Refer to Data Sheet. All other pressure
measurements require the port to be opened to atmosphere. When in gauge mode, the
instrument shows the pressure difference between the reference port and the output port.
Note: This is not a true differential operation as there is no true differential calibration of the
sensor.
The transducer of the barometric reference option senses atmospheric pressure via the
reference port. When enabled, the port must be open to atmosphere.
The reference connection should be actively used (differential connection option) for precision
low pressure measurement. The instrument measures pressure relative to the pressure at the
reference port.
An atmospheric pressure change causes the indicator to adjust the displayed pressure. This
appears as instability. To keep a stable displayed pressure, the reference port should be
restricted. Using a reference port restrictor (snubber), short term ambient pressure variations can
be prevented from affecting indicator performance.
The indicator and UUT references should be connected together, using the optional differential
connection kit, to provide a common reference to atmosphere.
6.3 Measure Setup
6.3.1 Pressure Zero
During use, the instrument pressure sensor can show small zero shifts caused by time and
temperature changes. Regular “zeroing” increases measuring precision.
6.3.2 Process
Selects display processing features that change the reading, as follows:
Option Description
% Pressure can be displayed reading as a percentage of full-scale or as a
percentage of a specified span.
Filter The displayed reading can be filtered by a custom low pass filter or the filter can
be disabled (default disabled). The indicator works at a speed independent of the
filter time constant.
Tare A specific tare value can be selected or the current displayed pressure reading
can be “captured” as the tare value. The display shows the selected tare value
in the pressure window.
Peak Maximum, minimum and average display of pressure readings.