4-6 Model 3750 Condensation Particle Counter
Temperatures
The temperatures of the condenser, saturator, and optics are displayed on
the Status screen. Temperatures are controlled through feedback circuits
on the main electronics board. For ambient temperatures outside the
instrument operating range, the instrument temperature performance may
not be maintained. Moderate increases in saturator temperature and optics
are tolerated in some instances, depending on measurement requirements.
In addition to condenser, saturator and optics, the CPC cabinet
temperature is displayed.
Figure 4-4
CPC Status Screen – Internal Parameters
Pressures
The pressures displayed are:
Ambient Pressure: Atmospheric pressure measured inside the CPC
case. The instrument is designed to operate in an ambient pressure
between 75 and 105 kPa.
Inlet Pressure: Differential pressure measured relative to ambient.
This pressure is typically approximately 0kPa when sampling directly
from the ambient environment. A restriction at the inlet will change the
Inlet Pressure. When sampling with tubing, the inlet pressure should
be maintained between +5 and -5 kPa.
Critical Orifice Pressure: Differential pressure across the sensor flow
critical orifice.
Aerosol Nozzle Pressure: Differential pressure across the aerosol
nozzle.
Vacuum Pressure: The total pressure applied by the vacuum pump.
Identification of the orifice and nozzle are found in the flow schematic in
Chapter 5.
To Next Page
Need help?
General
