Hach MET ONE 3411 Manuel D'utilisation page 14

Connect to clean dry air (optional)
Make sure that all the components installed before the particle counter,
including interconnecting lines, are pressure rated for higher than
150 psi.
Use a clean dry air (CDA) purge in high vapor areas to minimize
contamination of the sensor. The CDA purge typically consists of a
pressure source (40–120 psi, 100 psi nominal), a desiccator and an
absolute 0.1 µm filter. The CDA will use approximately 0.1 CFM at
atmospheric pressure.
1. Connect the purge air line to the CDA purge connector on the
particle counter. Refer to Figure 2
inch NPT fitting.
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on page 9. Use the supplied /
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2. Switch on the particle counter.
3. Switch on the purge air.
Connect RS485 communication (optional)
To connect for RS485 communication, refer to the illustrated steps that
follow.
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