Donaldson Company, Inc.
6
Standard Features
In sections Airflow, Filter Pressure Drop, Setpoint
Indicator, and illustrations Airflow Display and
Filter Pressure Drop and Setpoint Indicator Display
are descriptions and illustrations of two of the
windows located on the cover of the Checker board
enclosure.
ON Display
The green ON indicator light on the control display
indicates that the board is activated by an external
voltage source, usually the control voltage that
actuates the blower motor starter.
Airflow
The airflow window display uses a light bar to
indicate the operating position based on the airflow
or fan curve information placed in the
microprocessor memory at start-up.
The light bar has 10 segments. From left to right,
the first two are red, the second two are amber, and
the remaining six are green. The initial reading at
start-up should be in the green range. As the filters
accumulate dust, the airflow indicator will move;
the first amber light indicates that the collector
airflow is approximately 40-50 percent of full rated
flow, the first red light indicates a flow of
approximately 25-33 percent of the full rated
airflow. One light is illuminated at a time and
indicates the relative position within the range.
Included with the enclosure are two stickers to be
used on the Checker board display. Apply one
sticker under the circles on the airflow display.
Write in the appropriate airflow as measured in the
system. These measurements can be determined
during start-up and calibration. See Start-Up,
Calibration, and Adjustment on Page 20.
Airflow Display
Filter Pressure Drop
A single window alternately displays the filter
pressure drop and the relative setpoints.
The pressure drop indicator uses a light bar to
indicate the amount of static pressure required to
move the air from the dirty-air chamber to the
clean-air chamber. The light bar has 10 segments.
From left to right, the first six lights are green, the
next two are amber, and the final two are red. Each
light indicates a 3/4-in pressure drop. The display
provides a linear division of the available static
pressure. One light is illuminated at a time and
indicates the relative position within the range.
Filter Pressure Drop and Setpoint Indicator
Red
Amber
Green
SET POINT INDICATOR
FILTER PRESSURE DROP
P
1.5 3.0 4.5 6.0 7.5
"wg
AIR FLOW
1000*
3000*
7000*
5000*
Airflow, cfm
Red
Amber
Green
*representative values only
