Dwyer HFO - Manual (Page 3)

White Both Common Terminal #1 of DIN
Black Decreasing N.O. Terminal #2 of DIN
Contact
Red Increasing N.O. Terminal #3 of DIN
Contact
Green Enclosure Ground Terminal “G” of DIN
Precautions:
• Be certain to properly ground the unit via the
ground (G) pin located on the unit’s DIN
connector.
• In order to avoid accidentally removing the
switch glide screw, never loosen it by more than
one or two turns. This screw can be difficult to
replace if accidentally removed.
• Avoid over tightening the switch glide screw.
• When the switch adjustments are complete,
make certain that the wires that are attached to
the switch have not been moved into a location
that will interfere with the follower or the switch
lever.
• Do not make any modifications to the unit’s
internal wiring.
Electrical Connections:
Standard Flow Alarms are pre-wired with 4-pin
DIN connectors which consist of a male section
as shown in Illustration 4 and the female section
shown in Illustration 5. To open the female
section, first remove the screw, then lift the
connector portion out of the casing by inserting
the head of a screwdriver into the
slot marked for that purpose. Illustration 6
shows the disassembled female section.
Illustration 7 shows the connections for the low
alarm switch as the unit is shipped from the
factory. The wiring code below identifies how
the DIN connector is configured for dual alarms.
If the NC contacts are needed for either switch,
a simple adjustment must be performed. On the
switch itself, disconnect the NO lead from the
quick connect terminal, and place it onto the NC
contact. This will change the operating condition
of that particular alarm switch.
Wiring Code: Dual Switch Alarm
Illustration 4 Illustration 5
Illustration 6
Illustration 7, Low Alarm