Cut Sheet

© 2016 Littelfuse Protection Relays & Controls
www.littelfuse.com/
Rev: 1-A-062716
Protection Relays
Pump Controls and Liquid Level Controls
www.littelfuse.com/llc1
LLC1 SERIES
Description
The LLC1 Series is a single probe conductive liquid level control
designed for OEM equipment and commercial appliances. This
unit may be ordered with fixed fill or fixed drain operation. A
time delay (1-60s) prevents rapid cycling of the output relay.
On adjustable units, the sensitivity adjustment allows accurate
level sensing while ignoring foaming agents and floating
debris. Isolated AC voltage is provided at the probe to prevent
electrolysis. A trickle current of less than 1mA determines the
presence or absence of liquid between the probe and common.
The LLC1 Series printed circuit board is conformal coated to
resist moisture and corrosion.
Operation
Drain (Pump-Down Mode): When the liquid level rises and
touches the probe, a fixed 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 energizes and remains
energized until the liquid level falls below the probe. The output
relay then de-energizes and remains de-energized until the liquid
again touches the probe.
Fill (Pump-Up Mode): When the liquid level falls below the
probe, a fixed 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 energizes and remains energized until
the liquid level rises and touches the probe. The output relay
then de-energizes and remains de-energized until the liquid level
again falls below the probe.
Features & Benefits
FEATURES BENEFITS
Isolated AC voltage
on probe
Prevents scale buildup on the probe
Open PCB design
Cost effective design for OEM equipment and
commercial appliances
Conformally coated PCB Protects against moisture and corrosion
Sensitivity adjustment
Provides accurate level sensing while ignoring foam
or floating debris
Wiring Diagram
Open Board Liquid Level Controls
L1 N/L2
Metal Tank or us
e
additional Probe
C
P = Probe
L = Load
V = Voltage
∆S = Sensitivity
Adjustment
Contacts A, B & C
are isolated.
Connect common to
conductive tank or
an additional probe
as required.
Ordering Information
MODEL
INPUT
VOLTAGE
OPERATION
TIME
DELAY
SENSE
RESISTANCE
MOUNTING
LLC14A1AX
120VAC
Drain 1s Adjustable 0.5 in nylon standoffs (3)
LLC14A5AX
120VAC
Drain 5s Adjustable 0.5 in nylon standoffs (3)
LLC14B15AX
120VAC
Fill 15s Adjustable 0.5 in nylon standoffs (3)
LLC14B1AX
120VAC
Fill 1s Adjustable 0.5 in nylon standoffs (3)
LLC14B60AX
120VAC
Fill 60s Adjustable 0.5 in nylon standoffs (3)
LLC16A25AX
230VAC
Drain 25s Adjustable 0.5 in nylon standoffs (3)
LLC16A3AX
230VAC
Drain 3s Adjustable 0.5 in nylon standoffs (3)
If you don’t find the part you need, call us for a custom product 800-843-8848