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SPCL36104-S Suction System
9.8.5 “Delta-P” (Pressure Drop) Across the Cartridges
A sufficiently thick coating of dust must build up on the cartridges to cause a pressure
drop of 2” to 3” as read on the magnehelic or photohelic gages on the Dust Collector.
Cartridges that are too clean do not filter well and may be damaged.
9.8.6 Reverse Pulse Cleaning
The Dust Collectors clean the filter cartridges by sending large pulses of air in the
opposite direction (back down through the cartridge) to “puff out” and blow the dust
off.
TOO MUCH PULSING IS UNNECESSARY. IT WASTES COMPRESSED AIR
AND MONEY, AND PREVENTS THE FILTER CARTRIDGES FROM
GETTING PROPERLY SEASONED.
Dust Collector with Magnehelic Gage
The Reverse Pulse feature is always on. The only control over the frequency of
pulsing is a timer which usually sets the Dust Collectors to pulse every 10 seconds.
The maximum duration between pulses possible is 30 seconds.
SET THE PULSE
INTERVAL TO 30 SECONDS
. You may have to adjust back to more-frequent
pulses if the pressure drop across the cartridges starts to exceed 3 inches.
Dust Collector with Photohelic Gage
This control gives the operator the ability to adjust the pulsing of the Dust Collector.
Instead of the pulsing timer being on all the time, the photohelic gage senses the
pressure drop across the filters and only energizes the timer when the pressure drop
gets too high indicating that the cartridges are dirty.
THE RECOMMENDED
SETTING IS 2 INCHES TO 4 INCHES
. When adjusted this way, the pulsing
won’t happen until the cartridges experience more than 4 inches of pressure drop.
They will keep cleaning until the pressure drop comes down to 2 inches. With this
control system, the factory setting of 10 seconds between pulses is acceptable.
This
type of control system is the most cost-effective, and results in the longest-
possible filter life
. If your Dust Collector wasn’t purchased with a Photohelic Gage,
they may be added at a later date.
NOTE:
Proper operation of the pulse sequencing on photohelic systems depends upon
maintaining constant power to the Pulse Timer Package. This guarantees that the
cartridges are pulse-cleaned in the proper order. Without constant power, the control
package has no memory to tell it which cartridge was cleaned last. It will always start
over by cleaning Cartridge #1 when the Pulse Timer is energized. As such, the other
cartridges may never get cleaned.
