Description

The LLC4 combines resistance sensing circuitry with solid-state

timing to provide single probe level maintenance. On adjustable

units, the sensitivity adjustment allows accurate level sensing

while ignoring foaming agents and floating debris. Isolated

12VAC is provided at the probe to prevent electrolysis. A trickle

current of less than 1mA determines the presence or absence

of conductive liquid between the probe and common. The LLC4

Series can be used with many types of low voltage (resistance

changing) transducers to perform other control functions like

temperature limit control, photo limit control, condensation

sensing, and ice sensing.

Operation

Drain (Pump-Down Mode): When the liquid level rises and

touches the probe, the time delay begins. This time delay

prevents rapid cycling of the output relay and its load. At the

end of the time delay, the output relay energize and remain

energized until the liquid level falls below the probe level. The

output relay de-energize and remain de-energized until the liquid

rises and touches the probe.

Fill (Pump-Up Mode): When the liquid level falls below the

probe, the time delay begins. This time delay prevents rapid

cycling of the output relay and its load. At the end of the time

delay, the output relay energize and remain energized until the

liquid level rises and touches the probe. The output relay then

de-energize and remain de-energized until the liquid level again

falls below the probe level.

FEATURES BENEFITS

Isolated 12VAC probes Prevents scale buildup on probe

Industry standard 8-pin

octal plug connection Eliminates need for special connectors

Sensitivity adjustment Provides accurate level sensing while ignoring foam

or floating debris