Dalamatic Cased, DLMC 1/2/15 through 4/8/15
26
Delta P Control
For complete information, see the most current version
of the Delta P Installation, Operation, and Maintenance
manual.
Description
The Delta P Controller monitors the differential pressure
between the clean-air and dirty-air plenums, providing a
visual display of the filter condition. When combined with
a pulse timer, it manages the pressure drop by turning
the cleaning mechanism On and Off at the chosen limits.
There are three (3) set points: High Pressure On, Low
Pressure Off, and Alarm. The first two, High Pressure On
and Low Pressure Off, control the filter cleaning system.
The third, Alarm, provides a relay output to activate an
external alarm supplied by others.
Operation
Normal
The Delta P Controller monitors the pressure in the
clean-air and dirty-air air plenums while the collector
is running. The blower draws air through the filters,
creating a pressure drop. The Delta P Controller
measures the pressure drop and provides a visual
display in inches water gauge or metric (SI) collectors of
daPa.
Filter Cleaning
When the pressure drop across the filters reaches the
High Pressure On setpoint, the controller closes an
output relay allowing a timer to trigger the cleaning
valves sequentially. When the controller senses that the
pressure drop has decreased to the Low Pressure Off
setpoint, the relay opens and the cleaning cycle stops.
This sequence continues as long as the collector is
in use, maintaining the pressure drop within a narrow
range.
Alarm
The Alarm setpoint is set to a higher setting than the High
Pressure On setpoint used to start the filter cleaning
cycle. It indicates situations when the cleaning system
cannot reduce the pressure drop due to cleaning system
failure, lack of compressed air, or the end of the filter’s
useful life. There is a time delay prior to setting the Alarm
to prevent nuisance trips. The Delta P Controller also
provides an input connection for a remote alarm reset.
Delta P Control Display
Summary of Contents for Dalamatic Cased DLMC 1/2/15
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