US Water Systems Defender 223-DFROM Series, Owner'S Manual

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The DEFENDER systems are equipped with a switch closure circuit that control the RO system ON/OFF. This
is a “ no voltage ” switch closure circuit (dry contact).
Tank Level Input
There is a switch closure circuit used to turn some RO systems on and off when an atmospheric tank float is
installed. The float switch wires as follows;
The wire colors above show color coatings. However, the colors don ’ t matter. There is no voltage to these
wires. They just need to be wired in a loop that can open or close when necessary. BE SURE to use the blue
and black wires only on the float.
IMPORTANT! Do not apply voltage to the tank level input circuit. This
will damage the RO system .
Pretreatment Lockout Wiring
In some applications there are backwashing filter units or softeners used as pretreatment for the RO module.
Some of these pretreatment units may be equipped with a “ lockout ” output. In this case these can be wired
into the tank float loop. This will shut the RO module down while the backwashing filter or softener is in regen-
eration/backwash. This option is utilized to ensure there is no untreated water fed to the RO system when a
pretreatment device is in regeneration/backwash. The pretreatment output switches will be wired as follows;
The wire colors above show color coatings. However, the colors don ’ t matter. There is no voltage to these
wires. They just need to be wired in a loop that can open or close when necessary. BE SURE to use the blue
and black wires only on the float.
IMPORTANT! Do not apply voltage to the float connection circuit. This
will damage the RO system. BE SURE the pretreatment
output switch DOES NOT supply power.
RO
Tank Float
Connection
Storage
Tank
Float Switch
Tank Level and Pre - treatment Lockout Wiring
Backwashing
Filter
Or
Softener
RO
Tank Float
Connection
Common
Black
Storage
Tank
Float Switch
NC
Yellow