Omron K8AK-LS User Manual

New Product

For the most recent information on models that have been certified for
safety standards, refer to your OMRON website.

PH-1

PH-2

Protective Cover
(Electrode Holders for the PS
or BF Series)

Mounting Piece
(Electrode Holder for the PS Series)

Separator (to prevent contact between electrodes)

Conductive Level Controller

K8AK-LS

Ideal for Liquid Level Control in
Industrial Facilities and Equipment.

• Self-holding circuit implemented with circuit processing that is
not depending on external wiring.

• Switch between water supply and discharge with a DIP switch
setting.

• Sensitivity adjustment of operating resistance from 10 to 100 kΩ
for application to a wide range of liquids.

• Prevents chattering of relay contacts that occurs with ripples.

• Easy wiring with ferrules.

•Use 2 × 2.5 mm

• Applicable as a floatless switch.

2

solid wire or 2 × 1.5 mm2 ferrules.

Refer to Safety Precautions on page 7.

Ordering Information

Power supply voltage Model

24 VAC/DC K8AK-LS1 24 VAC/DC
100 to 240 VAC K8AK-LS1 100−240 VAC

Accessories (Order Separately)

●Electrode Holders/Underwater Electrodes

Application

Model PS-3S/-4S/-5S

Appearance

For general-pur­pose use, such as
water supply lines

For areas with
limited space

PS-31

SUS304, 300 mm

For liquids with
low resistance

BF-1 BF-3/-5 BS-1 BS-1T PH-1/-2

When mounting
strength is re­quired

●Electrode Rods

Electrode Rods are available in sets with the connection nuts, lock nuts, and tightening screws.

For resistance to
high-temperature
or high-pressure
liquids

For resistance
against corrosion

SUS

HAS
titanium

For installation at
long distances
from the liquid level

Application Purified water service, industrial water, and sewage

Model F03-60 SUS304 F03-60 SUS316

●Others

Item Model

Purified water service, industrial water, sewage, and weak
alkaline solutions

F03-11

F03-12

F03-14 1P (one pole)
F03-14 3P (three poles)
F03-14 5P (five poles)

1

K8AK-LS

Ratings and Specifications

Ratings Specifications

Power supply voltage

Voltage across electrodes

Power consumption

Operating resistance 10 to 100 kΩ (variable)
Reset resistance 250 kΩ max.

Response time Approx. 0.1 to 10 s (variable)

Length of cable

Indicators PWR: Green, RY: Yellow

Output contact ratings

Ambient operating
temperature

Storage temperature −25 to 65°C (with no condensation or icing)

Ambient humidity 25% to 85% (with no condensation)

Storage humidity 25% to 85% (with no condensation)

Altitude 2,000 m max.

Terminal screw
tightening torque

Case color N1.5

Case material PC and ABS, UL 94 V-0

Weight Approx. 150 g

Mounting Mounts to DIN Track.
Dimensions 22.5 × 90 × 100 mm (W×D×H)

24 VAC 50/60 Hz or 24 VDC
100 to 240 VAC 50/60 Hz

5 V p-p (Approx. 20 Hz)

24 VAC/DC: 2.0 VA/1.1 W max.
100 to 240 VAC: 4.6 VA max.

100 m max. (fully insulated 3-core 0.75-mm
tyre cable, 600 V)

Rated load

Resistive load
5 A at 250 VAC

5 A at 30 VDC
Maximum switching capacity: 1,250 VA, 150 W
Minimum load: 5 VDC, 10 mA (reference values)
Mechanical life: 10 million operations min.
Electrical life:
5 A at 250 VAC or 30 VDC: 50,000 operations
3 A at 250 VAC/30 VDC: 100,000 operations

−20 to 60°C (with no condensation or icing)

0.49 to 0.59 N·m

2

cab-

Operating voltage
range

Installation environ­ment

Approved standards EN 61010-1

EMC EN 61326-1 Industrial electromagnetic environment

Safety standards

Insulation resistance

Dielectric strength

Noise immunity

Vibration resistance

Shock resistance 100 m/s2, 3 times each in 6 directions along 3 axes

Degree of protection Terminals: IP20

85% to 110% of rated voltage

Installation category II, pollution level 2

UL 508 (Recognition),
Korean Radio Waves Act (Act 10564),
CSA: C22.2 No.14, CCC: GB14048.5

20 MΩ min.

Between all external terminals and the case
Between all power supply terminals and all input
terminals
Between all power supply terminals and all output
terminals
Between all input terminals and all output termi­nals

2,000 VAC for 1 min

Between all external terminals and the case
Between all power supply terminals and all input
terminals
Between all power supply terminals and all output
terminals
Between all input terminals and all output termi­nals

1,500 V power supply terminal common/normal
mode
Square-wave noise of ±1-μs/100-ns pulse width with
1-ns rise time

Frequency: 10 to 55 Hz, acceleration 50 m/s
10 sweeps of 5 min each in X,Y, and Z directions

2

2

Connections

Terminal Diagram

K8AK-LS1 100-240VAC

AB

K8AK-LS

Control Output

Relay output

250 VAC, 5 A (resistive load)
30 VDC, 5 A (resistive load)

Relay Output

Common

11 14 12

11 14

E1 E2 E3

B Power Supply Voltage

100 to 240 VAC 24 VAC/DC

A2

A1

A2A1

A1

(No polarity)

Note: 1. Do not connect anything to terminals that are shaded in gray.

2. Use the recommended ferrules if you use twisted wires.

Wiring Example

L1

Three-phase
power supply

L2

L3

12

A Water Level Inputs

LS1

E1 E2 E3

Water or
other liquid

A2

Power
supply voltage

12

14

11

E1 E2 E3

A2

A1

A1 A2

Power supply

AC/DC

Motor

Pump

Water or
other liquid

Source of liquid

Pump motor protection mechanisms have been omitted.

3

K8AK-LS

Timing Charts

●DIP Switch Pin 1: OFF (Automatic Liquid
Supply Operation)

Power supply voltage A1-A2

Electrode terminals E2-E3

Electrode terminals E1-E3

Control output terminals 11-14
(operation indication)

P

OFF (stop)

ON (start)

•

When the liquid level falls to E2 (indicator turns ON), the pump starts.

1

E

E

2

When the liquid level rises above E1 (indicator turns OFF), the pump stops.

E

3

Operation indicator OFF

Operation indicator ON

●DIP Switch Pin 1: ON (Automatic Liquid
Discharge Operation)

Power supply voltage A1-A2

Electrode terminals E2-E3

Electrode terminals E1-E3

Control output terminals 11-14
(operation indication)

E

1

E

2

E

3

•

When the liquid level reaches E1 (indicator turns ON), the pump starts.

OFF (stop)

When the liquid level falls below E2 (indicator turns OFF), the pump stops.

Operation indicator ON

ON (start)

Operation indicator OFF

P

4