Merck 1.44093.0001, Руководство по эксплуатации

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Compressed Gas Adapter (CGA)
Compressed Gas Adapter Packing List
Upon receipt you will receive the following items with your purchase:
1 - CGA Assembly which includes the Compressed Gas Adapter and Wall Mount
1 - Owners Manual
1 - 1 meter of tubing
safety During Operation
WARNING:
Indicates a potentially hazardous situation which, if instructions are not followed, could result in injury.
CAUTION:
Indicates a situation which could potentially affect your final results.
NOTes:
Indicates that an alternate procedure may need to be taken depending on the device which you are using.
Introduction
The Compressed Gas Adapter (CGA) is an accessory used with the APC ErgoTouch Pro 2, APC Handheld, APC Portable, APC M3 and
APC SmartTouch Airborne Particle Counters to monitor the particulate content of compressed gasses. It is routinely used in areas
where specified particle counts must not be exceeded due to legal requirements or individual standards. This manual describes the
procedures to install, use and clean this device in a safe manner.
Background
Compressed air and Nitrogen are used for many applications within various industries. In particular, cleanrooms use compressed gas-
ses to operate equipment and clean manufactured products. Since the cleanliness of the compressed gas affects both the cleanroom
and the products manufactured therein, it is essential to quantify the particulate levels in it.
All APC Airborne Particle Counters are designed to handle gasses at atmospheric pressure only. Therefore, without a Compressed Gas
Adapter, a particle counter cannot sample directly from a compressed gas line. Using a standard particle counter to sample a com-
pressed gas line is unsafe and can damage the particle counter. The Compressed Gas Adapter (CGA) provides a convenient interface
between a compressed gas line and particle counter.
Product Details
A particle counter requires air at atmospheric pressure and a nominal air velocity of about 0.5 meters per second (m/s). The CGA uses
an orifice to lower the pressure from the compressed gas line to atmospheric pressure. In addition, the orifice restricts the flow rate of
the gas to slightly above the flow rate required by the particle counter. As the air enters the diffuser cone, the velocity of the gas is
reduced, and provides a more uniform flow to an isokinetic probe. The isokinetic probe is connected to the inlet of the particle coun-
ter via a short length of tubing and provides the gas sample to the counter. The excess gas from the diffuser cone flows past the iso-
kinetic probe and then through a baffle to quiet the flow from the orifice. It then exits the CGA via the vent port, which may be open
to the cleanroom or exhausted outside of the cleanroom using tubing.
WARNING:
If the vent port is sealed while the adapter is connected to the gas line, pressure will build up inside of the diffuser, potentially
causing harm to the user. Visually make sure that the vent port is not sealed before using.
An orifice is used as a pressure/flow control device. Since the CGA is designed for output flow rates ranging from 0.1 cubic feet per
minute to 100 litre per minute, different orifice sizes must be used, depending on the output flow rate and the inlet pressure. For
each output flow rate (0.1 cubic feet per minute, 1 cubic feet per minute, 50 litres per minute, 75 litres per minute, 100 litres per
minute) a complete set of orifices is provided to cover an inlet pressure range from 10 PSIG up to 150 PSIG. (As the output flow rates
vary depending on the model of particle counter these orifice sets are not included in this product, they are seperate items.) Each ori-
fice has a number stamped on it, and these numbers uniquely identify the orifice.