Merck 1.44093.0001, Руководство по эксплуатации

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NOTe:
For APC Handheld counters (0.1 CFM), remove the isokinetic probe from the counter and install the included Inlet Adapter
into the inlet port or top of the counter. Make sure that the adapter seals properly against the O-ring in the counter inlet.
5. Determine how the excess gas will be vented (Section 6).
6. Turn on the pressure line.
CAUTION:
Make sure that you turn on the pressurized gas line first and that it is flowing into the particle counter before beginning
a count cycle. If not followed you will pull air in through the exhaust port!
7. Turn on the particle counter.
8. Begin your count cycle as usual.
WARNING:
Dangerous gasses such as Oxygen and toxic gasses should not be sampled using the CGA. If the CGA will be used with gasses
other than air or Nitrogen please contact Merck for more information.
CONNeCTING the VeNT PORT
The vent port provides a path to exhaust the excess gas from the CGA. There are three commonly used procedures for venting the
excess gas coming from the CGA.
If it is:
• Acceptable to vent the gas into the cleanroom
– Leave the vent port open.
• Acceptable to vent the gas into the cleanroom, but a few meters away from the CGA location
– Then install the included outlet nozzle into the vent port of the CGA. Next, connect a ¼ inch tubing to this port
to direct the vented gas to an acceptable location, such as to the outlet ducts of the cleanroom.
• Unacceptable to vent the excess gas into the cleanroom
– The tubing may be run from the CGA vent port to a port in the cleanroom barrier to exhaust the gas to the air
outside of the cleanroom.
WARNING:
The vent port must have a clear path from the vent port to the atmosphere. At no time should the vent port be closed off,
blocked or sealed. This port ensures that the pressure inside of the Compressed Gas Adapter remains at atmospheric pressure.
If the vent port is blocked, the device may become pressurized, and could cause damage to the particle counter.
Aseptic areas are typically maintained at a more positive pressure than their surrounding rooms in order to keep the flow of air moving
from a more positive to negative environment. For the APC Airborne Particle Counters, it is recommended to vent the gas into the
cleanroom, especially if the pressure inside of the cleanroom is higher than atmospheric pressure (typically 14.7 PSI) or is more than
about an inch or two of water (less than about 5 millibars). If the cleanroom is at a positive pressure and the exhaust gas is vented
out of the cleanroom to an environment that is at negative pressure, then the pressure inside of the CGA is equal to the pressure out-
side of the cleanroom. However, the pressure at the output of the particle counter is slightly higher because it is located within the
positive pressure environment. Since the APC is not designed to adjust the flow rate according to different pressures, it is highly rec-
ommended to vent the air into the same area where the compressed gas is being sampled. Pressure will affect the flow rate of the
particle counter.
In addition, please note that if the tubing connected to the vent port is longer than 5 meters (or 15 feet), use 1/2 inch ID tubing instead
of the 1/4 inch ID tubing provided with your airborne particle counter and CGA. The larger ID tubing will offer much less resistance
to the air flow than the 1/4 inch tubing. Also, you will need to use a barbed fitting adapter for the larger size tubing. This should be
placed on the vent port of the compressed gas adapter.