CRESSTO - SP series - datasheet - differential pressure transmitter0 pages
CRESSTO
intelligent low pressure transmitter
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very high sensitivity
overpressure endurance
uP signal processing
users SW configuration
analogue, digital and two-state
outputs
supply 5 ÷ 36 V
robust construction
protection IP65
wide temperature range
display fit-out possibility
These pressure transducers are designed for low and very low
pressures and pressure differences measuring. They may be
used in wide application in a branch of air-conditioning, ventilation, combustion process control, clean rooms monitoring, equipment design, etc. These transmitters can measure positive
and/or negative pressure differences or overpressure and/or
underpressure against ambient atmosphere, eventually measuring of absolute or barometric pressure.
The medium being measured may be a non-aggressive gas;
some exceptions must be consulted with producer. Measured
media is in a contact directly with silicon diaphragm, nickel
plated brass, silicone rubber, plastics polyetherimid. Pressure
connections are optional. All components of the transmitter are
placed in robust box from aluminum alloy, which serves as a
good mechanical and electrical protection. The box is fixed by
two screws, which are accessible after disclosure the lid and are
out of the sealed internal space, so that protection is IP65. For
electrical connection serves internal terminal block with screws
for cable with metal grommet PG-9. For some outputs can be
used also sealed latched mini connector type DIN 43650 - C with
cabel grommet PG7, witch enables to use cable diameter of
max. 6,5mm.
This type of transducer measures the pressure by means of a
silicon diaphragm on a piezoelectric principle. Therefore this
transducer attains a good overload endurance, is resistant
against vibrations and output is independent on work position.
Electronic circuitry is realized by a surface mount technology
and for increasing protection is passivated by a coat.
CRESSTO
SP
Electric signal from sensor is after amplifying converted by 16bit
ADC to digital format. By means of two-dimensional polynomial
approximation of 3rd order transmitter is calibrated and temperature compensated. With special agreement it is possible to
compensate down to -20°C. Output pressure value can be read
directly via serial port RS485, RS 232 or USB. Transmitter has
special output stage, which convert calculated value to analogue
value 4-20mA (two-wire) or 0-20mA, 0-10V, 0-3V(three-wire).
Particular analogue outputs can be switch by software and it is
possible to change measuring pressure range and set other
parameters, for example damping etc. In addition it is possible at
analogue outputs to switch linear conversion characteristics to
switching two-state one and realize logic levels with voltage
output. Transmitters can be fitted with output switching module,
which has small relay with one contact and two independent
outputs with NPN transistors with open collector with LED indication. All switching parameters can be set only via software. Next
option is 4 or 5 digit LCD with white LED back lighting. There is
also place for FLASH memory, where can be stored measured
data with desired period (without timestamps).
Transmitters can be supply with DC voltage with wide range from
5 to 35 Volts. Change in this range has no effect to measurement
accuracy.
Software configuration is realized via special USB adapter with
program for Windows. Transmitter can be supplied from USB and
due to adapter totally DC isolation can be connected to PC
whenever in the final application.
Hasičská 2643, 756 61 Rožnov p. Radh., CZECH REPUBLIC
tel.: +420 571 843 162, 571 845 338, fax: +420 571 842 616
e-mail: firma@cressto.cz
www.CRESSTO.cz