Donaldson Company, Inc.
16
CUR 1, 2, 3
The Current, CUR 1, 2, and 3 connection blocks
provide input from an external set of current
sensors. See the wiring diagram for proper
connections. The current sensors measure the amp
draw of the blower motor and provides airflow
information through the light bar display.
Current Sensors
Relay 1 through Relay 24
Relay 1 is always used to control the pull-in coil on
the motor starter that starts and stops the system
blower. Relays 2 and higher provide control of the
system solenoid valves used for filter cleaning.
The relay outputs can be 115-Volt AC or 24-Volt
DC. The 24-Volt DC version has a transformer
that supplies DC current to the relays. The 24-Volt
DC version leaves Relay 2 blank to separate the
115 or 230-Volt AC motor starter voltage from the
24-Volt DC used for the solenoid valves.
Relays used for solenoid control can operate up to
three solenoids each. Do not connect more than one
solenoid on any air manifold to a common relay.
Relay 1 through 24
Relay #1
Relays
1 2
3 C
CUR 1
CUR 2
CUR 3
