
Donaldson Company, Inc.
18
CAUTION!
Electrical installation must be
performed by a qualified electrician
and comply with all applicable
national and local codes.
Turn power OFF during installation
or maintenance.
Do not install in classified hazardous
atmospheres without an enclosure
rated for the application.
Solid-State Timer Installation
The solid-state timer is an electronic timer used to
control the filter cleaning system. Available options
include 3, 6, 10, 20, and 32-pin solenoid valve
control.
Note: The solid-state timer requires a 105 to 135-
Volt customer-supplied power supply.
Do not mount the solid-state timer on the
unit. Mechanical vibration can damage the
control.
1. Using the wiring diagram supplied, wire the fan
motor, fan-motor starter, solid-state timer, and
solenoid valves. Use appropriate wire gauge for
rated amp load as specified by local codes.
2. Plug the program lug into the pin that
corresponds with the number of solenoid valves
controlled.
3. With power supply ON, check the operation of
the solenoid valves. The valves should open and
close sequentially at factory set 10-second
intervals.
4. If a Photohelic gauge or similar device is used to
control the solid-state timer and the jumper on
the pressure switch portion of the timer is
removed, the solenoid valves pulse only when the
differential pressure reaches the high-pressure
setpoint. The valves continue to pulse until the
low-pressure setpoint is reached.
Solenoid Connection
The unit is equipped with 115-Volt solenoid valves
that control the pulse-cleaning valves, which clean
the filters.
One of three types of solenoid enclosures, the
weatherproof NEMA 4 with 3D2 solenoids, the
explosion proof NEMA 7 with 5D2 solenoids, or the
explosion proof NEMA 9 with 5D2 solenoids,
is mounted near or on the units compressed-air
manifold.
Wire the solenoids to the solid-state timer following
the wiring diagram supplied with the unit. Filter life
and cleaning operation will be affected if not wired
correctly.
Timer and Solenoid Specifications
Power to the solid-state timer is supplied to
Terminals L1 and L2, which operate in parallel with
the fan starters low-voltage coil. On fan start-up,
power is supplied to the timer and the preset OFF
time is initiated. At the end of the OFF time, the
timer energizes the corresponding solenoid valve to
provide the ON time cleaning pulse for one
diaphragm valve and then steps to the next until all
filters have been cleaned.
To pulse when the fan is OFF, install a toggle switch
as shown on the Solid-State Timer Wiring Diagram.
When the toggle switch is ON, the timer receives
power and energizes the solenoid valvespulse-
cleaning operation even though the fan is turned
OFF.
Input
105-135V/50-60Hz/1Ph
Output Solenoids
The load is carried and turned ON and OFF by the
200 watt maximum-load-per-output solid-state
switch.
Pulse ON Time
Factory set at 100-milliseconds, or 1/10-second.
Note: Do not adjust pulse ON time unless the proper
test equipment is available. Too much or too
little ON time can cause shortened filter life.