Features
- Span: -14.7 ... 21 PSIG up to 0...8700 PSIG
- t max : 248 °F
- Process Connection: 1⁄2" NPT, 1⁄4" NPT, or Various Diaphragm Seals on Request
- Material: 316L Stainless Steel, HAST-C®, or
Tantalum
- Output: 4 ... 20 mA
- Sensor Input: Gauge or Absolute Pressure
- Self-Diagnostic Function: Sensor, Memory A/D Converter, Power etc.
- Digital Communication with HART ® Protocol
The KOBOLD Pressure Transmitter model PAS is a
microprocessor based high performance transmitter, which
has a scalable pressure calibration and output signal. It
automatically compensates for ambient temperature and
process variables. Communication with the instrument and
configuration of various parameters is possible via HART®
protocol. All of the sensor's data is input, modified and stored
via EEPROM.
Superior Performance
- High reference accuracy: ±0.075 % of calibrated span (optional: ±0.04 % of calibrated span)
- Long-term stability
- High rangeability (100:1)
Flexibility
- Data configuration with HART ® configurator
- Measurement of gauge or absolute pressure
Reliability
- Continuous self-diagnostic function
- Automatic ambient temperature compensation
- EEPROM write protection
- Fail-mode process function
Electronics module
The Electronics module consists of a circuit board sealed in
an enclosure. There is an MCU module, an analog module,
an LCD module, and a terminal module within the transmitter.
The MCU module acquires the digital value from the ana-
log module and applies correction coefficients selected from
EEPROM. The output section of the MCU module converts
the digital signal to a 4...20 mA output. The MCU module
communicates with the HART ® -based configurator or con-
trol system, such as DCS (Distrubuted Control System). The
power section of the MCU module has a DC-to-DC power
conversion circuit and an input/output isolation circuit. The
LCD module plugs into the MCU module and displays the
digital output in a user configured unit.
Sensor Inputs
The pressure transmitter model PAS is available as a piezo-
resistive pressure transmitter which measures gauge pressure
as well as absolute pressure. The sensor module converts
the resistance into a digital value. The MCU module calculates
the process pressure based on this digital value.
The sensor modules include the following features
- 0.075 % accuracy
- The software of the transmitter compensates thermal
effects, improving performance.
- Precise Input Compensation during operation is achieved
with temperature and pressure correction coefficients that
are characterized over the range of the transmitter and
stored in the sensor module EEPROM memory.
- EEPROM stores sensor information and correction
coeficients separately from MCU module, allowing for easy
repair, reconfiguration and replacement.
Basic Setups
The following settings can be easily configured from any host
that supports the HART ® protocol:
- Operational parameters
- 4-20 mA points (zero points/span)
- Engineering units
- Damping time: 0.25...60 sec
- Tag: 8 alphanumeric characters
- Descriptor: 16 characters
- Message: 32 characters
- Date: day/month/year
Calibration and Adjustment
- Lower/Upper range (zero/span)
- Sensor zero trimming
- Zero point adjustment
- DAC output trimming
- Transfer function
- Self-compensation
Self-Diagnosis and others
- CPU & Analog Module Fault Detection
- Communication error
- Fail-mode handling
- LCD indication
- Temperature measurement of sensor module
Process Connection Via Diaphragm Seals
For connecting the model PAS to different process
connections, diverse diaphragm seal versions are necessary.
They can be connected to the pressure transmitter directly or
via a capillary tube. Depending on the application; different
combinations of diaphragm seals, capillary tubes and fill
fluids are possible. To clarify those possibilities, the special
connections via diaphragm seals should be requested
separately from the pressure transmitter.