Model 306 Ozone Calibration Source Manual Rev. G-1
7
3.3
Model 306 Installation Guidelines
3.3.1 Typical Installation: Connection to a Device Drawing Flow from the Model
306
The Model 306 is often used to calibrate an ozone monitor or to provide a known
ozone concentration to another kind of equipment that draws flow from the calibrator.
The Model 306 is designed for this type of installation. Inside the Model 306, an air
pump maintains a total flow of ~ 4 L/min through the ozone generator. Any portion of
the total flow that is not being drawn into the user’s equipment is vented through an
internal ozone scrubber and vented inside the enclosure (Figure 3-1).
Figure 3-1.
Schematic of the Model 306 showing the internal overflow scrubber and vent for
any unused portion of the total flow rate.
3.3.2 Alternative Installation: Pushing Flow from the Model 306.
For some applications, it may be desirable to configure the Model 306 to push into a
chamber or other type of passive equipment that does not actively pull or push flow.
In the case that the equipment is not very restrictive and is near ambient pressure, the
Model 306 may provide enough flow (up to ~ 1 L/min) and will not need any additional
modification. If more flow is needed (up to ~ 4 L/min) or the chamber/equipment is
fairly flow-restrictive, a needle valve can be installed on the outlet of the internal
overflow scrubber (see Figure 3-2, next page). Adjustment of the needle valve will
control the portion of flow that is vented inside the box and the portion that is directed
to the outlet.
3.3.3
Suggestions for Measuring the Flow to the User’s Equipment
If the user wants to measure the flow rate delivered to their equipment, we suggest
they use one of the following methods:
1. Use a flow meter on the internal overflow scrubber to measure the vented flow
rate and read the total flow rate from the Model 306. The flow to the u
ser’s
equipment is the difference between these two measurements.
2.
Use a scrubber after the user’s equipment and then a flow meter. This allows
for direct measurement of the process flow, but may pressurize the process if
the scrubber or flow meter is restrictive. Ozone must be destroyed in the gas
stream using a scrubber to prevent damage to the user’s flow meter.
Model 306 Ozone Calibration Source
Internal
Overflow
Scrubber
Vent
Ozone
Generator
Air
Pump
User’s
Equipment
