Rae RAEGuard 2 PID - 18 General Information

RAEGuard 2 PID User’s Guide
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18 General Information
The DigiPID Sensor is a self-contained intelligent sensor module with
built-in photoionization detector (PID) sensor processor, lamp driver,
and analog and digital interface circuits. It is designed to detect
volatile organic compounds (VOC) and has a standard external
interface. This sensor module can be easily integrated into a wired or
wireless communication system for remote, wide-area, and pervasive
monitoring applications. The sensor module can be powered by a 5V
±0.25V DC power supply. It is housed in a weatherproof enclosure
with a standard 8-pin interface connector. The chart below details the
functions of the eight pins:
Pin
Number
1
2
3
4
5
6
7
8
Definition
Power
In
CS
Analog
Signal
Out
RXD
Open
Drain
GND
Control
Signal
(optional)
TXD
Notes:
Power in: Power supply input connector for the sensor module. The
input voltage range is DC 5V ±0.25V at 200mA.
CS: Communication Select. Select (falling edge) to start
communication, deselect (rising edge) to stop communication.
Analog Signal Out: Analog signal output with 1kΩ output resistance
for the sensor module. The output signal range is between 0.5V and
2.5V.
RXD & TXD: Serial interface poles (receive and transmit) for UART
mode with 3.3V TTL level.
Open drain: Switching signal output pole. It can deliver low or high
level to external equipment according to customer requirements.
GND: Power and signal ground.