Burr King BK75 - Manual (Page 17)

Donaldson Company, Inc.
16
Magnehelic Gauge
The Magnehelic is a differential pressure gauge
used to measure the pressure difference between
the clean- and dirty-air chambers and provides a
visual display of filter change requirements. The
high-pressure tap is located in the dirty-air
chamber and the low-pressure tap is located in the
clean-air chamber.
1. Choose a convenient, accessible location on or
near the unit for mounting that provides the
best visual advantage.
If unit is equipped with factory-installed pressure
taps, skip to Step 5.
2. Before drilling, place a piece of non-combustible
cloth over the filter opening in the clean-air
chamber to protect them from drilling chips.
3. Place a piece of wood behind the drill location
in the dirty-air chamber to protect the filters
from damage by the drill bit. Use a .406-inch
diameter bit to drill the holes as shown in
Magnehelic Gauge, Detail A.
4. Mount the pressure tap hardware on the clean-
air chamber panel. Mount the pressure tap with
the tee inside the dirty-air chamber.
5. Plug the pressure ports on the back of the gauge
using two, 1/8-in NPT pipe plugs supplied.
Install two, 1/8-in NPT male adapters supplied
with the gauge into the high- and low-pressure
ports on the side of the gauge. Attach the
mounting bracket using three, #6-32 x 1/4-in
screws supplied.
1/8-in NPT x 90°
male elbow
clean-air chamber
drill location, see detail A
3/8-in flat washer
1/8-in NPT coupling
mounting bracket
#6-32 x 1/4-in mounting screws
support structure
mounting surface
Magnehelic gauge
high-pressure port
low-pressure port
two, 1/8-in NPT
adapters
plastic tubing
two, 1/8-in NPT pipe plugs
two, self-drilling screws
1/8-in NPT x 90° male elbow
dirty-air chamber
drill location, see detail A
3/8-in flat washer
1/8-in NPT adapter
1/8-in NPT x 90° elbow
static pressure tee
Magnehelic Gauge Assembly