Protection Relays
Pump Controls and Liquid Level Controls
LLC2 SERIES
Open Board Liquid Level Controls
Description
The LLC2 Series is a dual-probe conductive liquid level control
designed for OEM equipment and commercial appliance
applications. Models are available for fill or drain operation.
Transformer isolated 12VAC is provided at the probes to prevent
electrolysis. A trickle current of less than 1mA determines the
presence or absence of liquid between the probes and common.
On adjustable units, the sensitivity adjustment allows accurate
level sensing while ignoring foaming agents and floating debris.
The LLC2 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 high probe, the output relay energizes and remains
energized until the liquid level falls below the low probe. The
output relay then de-energizes and remains de-energized until
the liquid again touches the high probe.
Wiring Diagram
Fill (Pump-Up Mode): When the liquid level falls below the low
probe, the output relay energizes and remains energized until
the liquid level rises and touches the high probe. The output
relay then de-energizes and remains de-energized until the liquid
level again falls below the low probe.
V = Voltage
L = Low Probe
H = High Probe
C = Probe Common
P = Probe
∆S = Sensitivity
Adjustment
NC = Normally
Closed
NO = Normally
Open
Features & Benefits
FEATURES
BENEFITS
Isolated 12VAC probes
Prevents scale buildup on the probes
Metal Tank or use
additional Probe
Cost effective design for OEM equipment and
commercial appliances
Open PCB design
Connect common to conductive tank. Additional
probe is necessary for non-conductive or
insulated tanks.
Conformally coated PCB
Sensitivity adjustment
Protects against moisture and corrosion
L1
N/L2
Provides accurate level sensing while ignoring foam
or floating debris
Accessories
P1015-13 (AWG 10/12), P1015-64 (AWG 14/16),
P1015-14 (AWG 18/22) Female Quick Connect
These 0.25 in. (6.35 mm) female terminals are
constructed with an insulator barrel to provide
strain relief.
Ordering Information
INPUT
SENSE
RESISTANCE
MODEL
OPERATION TERMINATION
VOLTAGE
P1015-18 Quick Connect to Screw Adapter
Screw adapter terminal designed for use with
all modules with 0.25 in. (6.35 mm) male quick
connect terminals.
Adjustable
to 100kΩ
120VAC
LLC24A2AN
LLC24A2F50N
LLC24B1AC
Drain
Drain
Fill
Terminal block
120VAC
120VAC
Terminal block Fixed 50kΩ
0.25”
Adjustable
Quick connect to 100kΩ
PHST-38QTN Electrode
Designed for a maximum steam pressure of
240 PSI; 400° F. UL353 Recognized.
0.25”
120VAC
120VAC
230VAC
LLC24B1F26C
LLC24B2F50N
LLC26A1F25C
Fill
Fixed 26kΩ
Quick connect
LLP-24 Threaded Probe (24”)
Threaded stainless steel probe measuring 24”
(61 cm) long. For use with PHST-38QTN liquid
level control electrodes.
Fill
Terminal block Fixed 50kΩ
0.25”
Drain
Fixed 25kΩ
Quick connect
If you don’t find the part you need, call us for a custom product 800-843-8848
© 2016 Littelfuse Protection Relays & Controls
www.littelfuse.com/llc2
Rev: 1-A-062716