Smart Photoionization Detector Module PIDS3
User Manual
PIDS3 - User Manual (en) - 1.03.docx
Analytical Control Instruments GmbH, Volmerstraße 9A, 12489 Berlin, Germany, www.aci-berlin.com
Page 20 of 58
6.4
Gas supply
NOTICE
–
WATCH THE GAS FLOW
The module requires a uniform gas flow.
Gas must be free of dust and liquids.
Dust and liquids must be kept away from module internal gas paths.
The module comes with an integrated gas flow monitoring. The current gas flow indicator can be read with
measurement values of UART command and Modbus data registers.
The module status information contains two flow indications:
•
‘flow low’
- gas flow too low, measurement result integrity loss and module may be damaged
•
‘flow over’
- gas flow too high, measurement result integrity loss
6.4.1
Using the internal optional pump
The internal optional pump ensures ambient measurement gas flow through the PID sensor.
For usage of a constant measurement gas source e.g., from a pressure line, the module gas input must be
bypassed.
NOTICE
–
WATCH THE GAS FLOW
Gas input must be nearly having ambient pressure (deviation recommended less than 20
mbar) in pump operation.
Constant flow from active gas source will need a bypass line for surplus measurement gas.
Gas source should support at least 400 ml/min to realize 200 to 300 ml/min flow in module.
Gas flow scheme with internal optional pump and constant flow of measurement gas source at gas input
PIDS MODULE
with optional pump
DUST AND WATER
PROTECTION FILTER
GAS
IN
GAS
OUT
at least 400 ml/min
MEASUREMENT
GAS ONLY SOURCE
Bypass out