700 CLD / O2
5-04-2017
7
Flow System
The flow system’s basic function is to deliver highly regulated flows of sample and air or
O
2
to the ozonator and reaction chamber assemblies. The EPC (electronic proportional
control) valve delivers approximately 15 PSIG (Standard without ozone pump option) to
a pre-set capillary and consequently accurately predetermines the ozone flow rate. The air
supply cylinder should be set to 25 PSIG.
Sample flows through the sample EPC valve, the NO/NO
x
solenoid valve, the sample
capillary and into the reaction chamber. The sample pressure is factory set to
approximately 3.85 PSIG (Standard without low pressure option). A close-coupled
bypass capillary minimizes dead volume and improves response time. Sample inlet
pressure and regulated air pressures are monitored by internal pressure transducers and
presented in PSIG via the Diagnostics screen.
NOTE:
The correct pressures are determined by the factory for optimal analyzer
performance and are recorded on the
Factory Settings Screen
in the analyzer.