Ametek WDG-V, Руководство пользователя

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PN 9000-133-VE, Rev U
Digital Input to Initiate Remote Calibration Unit
The digital input connections on the
Wiring
board allow you to initiate a
remote calibration from a remote location. For this option to work, you must
have a remote calibration unit. The system monitors the digital input, and
when the switch closes, it sends the system into an automatic calibration.
The
switch you connect to this digital input must be a normally open switch.
Digital input connections are labeled as follows on the
Wiring
board:
CIN
Notes About Ducting
Ducting Between Pressurized Enclosure and Inlet
The intake ducting to a compressor should not normally pass through a haz-
ardous area. If the compressor intake line passes through a hazardous area,
it should be constructed of non-combustible material and protected against
mechanical damage and corrosion. Adequate precautions should be taken to
ensure that the ducting is free from leaks in case the internal pressure is below
that of the external atmosphere. Additional protective measures (for example,
combustible gas detectors) should be considered to ensure that the ducting is
free of flammable concentrations of gas vapor.
Additional Purge Time to Account for Ducting
The purge duration should be increased by the time necessary to purge the
free volume of those associated ducts which are not part of the equipment
by at least five times their volume at the minimum flow rate specified by the
manufacturer.
Power for Protective Gas Supply
The electrical power for the protective gas supply (blower, compressor, etc.)
should be either taken from a separate power source or taken from the supply
side of the electrical isolator for the pressurized enclosure.
Enclosure Maximum Overpressure
The user should limit the pressure as specified by the manufacturer.
Installation and Start-Up
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