Donaldson Torit DFO 2-4, Инструкция по установке и эксплуатации

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Downflo Oval, DFO 2-4 and 3-6
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zero. After the blower has come to a stop, the Delta
P Plus engages the cleaning mechanism for a pre-
selected time.
3. Combined Differential and Down Time Cleaning
(ALL) - The Delta P Plus Control combines the two
functions described above; maintaining the pressure
drop in a narrow band and down time cleaning the
filters when the collector is shut down. The down
time cleaning function can be toggled On or Off from
the keyboard.
Alarm
The alarm setpoint is set to a higher setting than 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 Plus Control also provides an input connection
for a remote alarm reset.
For complete information, see the most current version of
the Delta P Plus Installation, Operation, and Maintenance
manual.
Delta P Plus Control
The Delta P Plus Control monitors the differential
pressure between the clean and dirty air plenums,
providing a visual display of the filter condition. When
combined with a pulse timer, it controls the pressure
drop by turning the cleaning mechanism On and Off at
the chosen limits. There are three (3) set points: High
Pressure Drop On, Low Pressure Drop Off, and Alarm.
The first two, High Pressure Drop On and Low Pressure
Drop Off, control the filter cleaning system. The third,
Alarm, provides a relay output to activate an external
alarm supplied by others.
The user can program the Delta P Plus Control to pulse
while the collector is running, to maintain a relatively
constant pressure drop across the filters, pulse only
after the collector is shut down (after-shift cleaning), or
a combination of both, cleaning while running as well as
end of the shift.
Operation
Normal
The Delta P Plus Control monitors the pressure on both
sides of the tubesheet while the unit is running. The
blower draws air through the filters, creating a pressure
drop. The Delta P Plus Control measures the pressure
drop and provides a visual display in inches water gauge
or metric (SI) units.
Filter Cleaning
The Delta P Plus Control offers three filter cleaning
options.
1. Differential Pressure Cleaning (DFF) - When the
pressure drop across the filters reaches the control’s
High setpoint, the control closes an output relay
allowing a sequential timer to trigger the cleaning
valves. When the control senses that the pressure
drop has decreased to the Low 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.
2. Down Time Cleaning (DTC) - The Delta P Plus Control
monitors the collection system. It watches for the
blower to start, the pressure drop to exceed the Low
setpoint, and then for the pressure drop to approach
Delta P Plus Control Display