Distech Controls PS-2AEULDP Series Manual de instalación - Página 4
Navegue en línea o descargue pdf Manual de instalación para Transmisor Distech Controls PS-2AEULDP Series. Distech Controls PS-2AEULDP Series 5 páginas. Ultra low pressure transmitter
Imprimir páginaConfiguration
The transmitter is configured with jumpers located on the circuit board as shown on the PCB drawing. These jumpers are used to select the output signal
type and the bipolar range/unipolar range (+/- or 0-MAX.) The unit is factory configured to operate in the 4-20 mA output mode. This can be changed to
the voltage mode by moving the jumper from the position marked 4-20 to the position marked VOUT.
For example, if the model is for 25 Pa and if the jumper labeled (+/-) is also selected, then the pressure range will be –25 to +25 Pa. This means that each
model has two pressure ranges, a bipolar range +/-, and a unipolar range, 0-MAX.
Pneumatic Connections
The two pressure ports on the end of the enclosure are labeled High and Low. The output signal reads a positive value when the port pressure is higher
on the High port than the Low port so ensure these ports are connected correctly. Use 1/8" to 3/16" ID flexible tubing for the pressure connections. Arrange
the tubing to minimize stress on the connections and ensure there are no kinks in the tubing. For most accurate measurements, do not leave the Low port
open to the atmosphere, run a return line from the Low port to the vicinity of the point being measured.
Ensure the tubing to be used is clean and do not allow material to fall into the pressure ports as contamination could damage the sensor. When removing
tubing use care to avoid breaking the ports. In some cases it is better to cut the tubing off rather than pulling it off but be careful not to cut the fitting or an
air leak may occur.
Power Up Instruction
Before turning on the power, verify all wiring to ensure that it complies with one of the included wiring diagrams and verify that the output signal type is
correctly selected with the jumpers. Also, review the specifications to ensure the power supply is correct and that the pressure is within the correct range.
At this time, also inspect the internal pressure tubing that connects the sensor to the external ports to ensure that the tubing did not get kinked during
installation.
Proper operation can be verified by measuring the output signal. For voltage output configuration, measure the voltage between the OUT and COM
terminals. The voltmeter should read between 0-10 Vdc. For current output configuration, insert a mA meter in series with the OUT terminal. The mA meter
should read between 4 and 20 mA.
Operation
If the unit is set to a unipolar range such as 0-25 Pa, then the pressure applied to the High port must be higher than the pressure applied to the Low port.
In this case, if the Low port is left open to ambient pressure and the High port is used to measure a positive pressure, then the output pressure can be
calculated as follows:
4-20 mA
0-10 Vdc
In the case of 0-25 Pa, 4 mA or 0 V = 0 Pa and 20 mA or 10 V = 25 Pa. Since the transmitter is linear, 12.5 Pa would be 12 mA or 5 V. If the positive
pressure connection is reversed then the transmitter will always output 4 mA or 0 V.
If the unit is set to a bipolar range such as ± 25 Pa, then the pressure applied to the High port should be higher than the pressure applied to the Low port
for a positive output response. In this case, differential pressure can be measured using both ports. If the High port has a positive pressure with respect
to the Low port, then the output indicates a positive pressure. Negative pressure is indicated if the High pressure is less than the Low pressure. For bipolar
ranges, the output pressure can be calculated as follows:
4-20 mA
0-10 Vdc
4/5
Pressure = [(Output current - 4 mA) / 16 mA] x Range
Pressure = (Output voltage / 10 V) x Range
Pressure = [(Output current - 4 mA) / 16 mA] x Range- Offset
Pressure = (Output voltage / 10 V) x Range- Offset