Optional Air Purge; Electrical Connections - Hach Lange CL17 User Manual

Installation
3.7

Optional air purge

3.8

Electrical connections

1 Intended for wiring relays. Use sealing type fittings.
2 Optional air purge connection
18
Air purge may be necessary if the analyzer is located in an environment with high
humidity and/or caustic vapors. The goal is to maintain a slight positive pressure in the
instrument with dry instrument air.
The air purge connection is located on the left side of the instrument enclosure.
To connect an air supply, remove the plug in the quick connect fitting then connect ¼-inch
poly tubing by pushing the tubing into the fitting. Two distinct "stops" will be felt as the
tubing is correctly attached. If the tubing is not properly seated, it will come loose when
air pressure is applied. Use only dry, oil-free instrument air at 15 scfh.
All power connections are made through the conduit openings in the upper left side of the
instrument. The instrument is shipped with plugs in all of the conduit openings. Wire the
instrument for power, alarms, and relay connections using sealing-type conduit fittings, to
maintain the IP62 environmental rating.
If connections are not made through a conduit opening, install a liquid-tight seal in place
of the plugs to maintain the IEC 529 IP62 rating. Refer to
page 49.
Figure 8 Location of air purge and electrical connections
3 Network and 4-20 mA connections. Use sealing type
fittings.
Note: If relay connections are not made, an liquid-tight seal
(4221000) must be installed to maintain the IEC 529 IP62
rating.
4 Power connections. Use sealing type fittings.
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