Omron K8AK-VS3, K8AK-VS2 User Manual

NEW Product

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

Single-phase Voltage Relay

K8AK-VS

Ideal for Voltage Monitoring for
Industrial Facilities and Equipment.

• Monitor for overvoltages or undervoltages.

• Manual resetting and automatically resetting supported by one
Relay.

• One SPDT output relay, 5 A at 250 VAC (resistive load).

• Output relay can be switched between normally open and
normally closed.

• Process control signal (0 to 10 V) and current splitter input
supported.

• Output status can be monitored using LED indicator.

• Input frequency of 40 to 500 Hz supported.

• Inputs are isolated from the power supply.

Refer to Safety Precautions on page 9.
Refer to page 8 for commonly asked questions.

Ordering Information

List of Models

Setting range Power supply voltage Model

1 to 10 V AC/DC
3 to 30 V AC/DC
15 to 150 V AC/DC

20 to 200 V AC/DC
30 to 300 V AC/DC
60 to 600 V AC/DC

24 VAC/DC K8AK-VS2 24 VAC/DC

100 to 240 VAC K8AK-VS2 100-240 VAC

24 VAC/DC K8AK-VS3 24 VAC/DC

100 to 240 VAC K8AK-VS3 100-240 VAC

Ratings and Specifications

Input Range

Model Range* Connection terminal Setting range Input impedance Overload capacity

0 to 10 V AC/DC V1-COM

K8AK-VS2

K8AK-VS3

* The range is selected using connected terminals.

0 to 30 V AC/DC V2-COM Approx. 320 kΩ
0 to 150 V AC/DC V3-COM Approx. 1.6 MΩ

0 to 200 V AC/DC V1-COM
0 to 300 V AC/DC V2-COM Approx. 1.7 MΩ
0 to 600 V AC/DC V3-COM Approx. 3.1 MΩ

1 to 10 V AC/DC,
3 to 30 V AC/DC,
15 to 150 V AC/DC

20 to 200 V AC/DC,
30 to 300 V AC/DC,
60 to 600 V AC/DC

Approx. 120 kΩ

Approx. 1.2 MΩ

Continuous input at
115% of maximum input
10 s at 125%
(up to 600 VAC)

1

K8AK-VS

Ratings

Power supply
voltage

Power consumption

Operating value setting range (SV)

Operating value 100% operation at set value

Reset value setting range (HYS.) 5% to 50% of operating value

Reset method

Operating time setting range (T) 0.1 to 30 s

Power ON lock time (LOCK) 1 s or 5 s (Switched using DIP switch.)

Indicators Power (PWR): Green, Relay output (RY): Yellow, Alarm outputs (ALM): Red

Input impedance Refer to Input Range on previous page.

Output relays One SPDT relay (NO/NC switched using DIP switch.)

Output relay ratings

Ambient operating temperature −20 to 60°C (with no condensation or icing)
Storage temperature −25 to 65°C (with no condensation or icing)

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

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

Altitude 2,000 m max.

Terminal screw tightening torque 0.49 to 0.59 N·m

Terminal wiring method

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×H×D)

Isolated power supply

24 VAC/DC
100 to 240 VAC

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

10% to 100% of maximum setting range
K8AK-VS2: 1 to 10 V AC/DC

K8AK-VS3: 20 to 200 V AC/DC

Manual reset/automatic reset (switchable)
Note: Manual reset: Turn OFF power supply for 1 s or longer.

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

Recommended wire

Solid wire: 2.5 mm
Twisted wires: AWG16, AWG18

Note: 1. Ferrules with insulating sleeves must be used with twisted wires.

Recommended ferrules

Al 1,5-8BK (for AWG16) manufactured by Phoenix Contact
Al 1-8RD (for AWG18) manufactured by Phoenix Contact
Al 0,75-8GY (for AWG18) manufactured by Phoenix Contact

3 to 30 V AC/DC
15 to 150 V AC/DC

30 to 300 V AC/DC
60 to 600 V AC/DC

3 A at 250 VAC or 30 VDC: 100,000 operations

2

2. Two wires can be twisted together.

2

Specifications

Allowable operating voltage range 85% to 110% of rated power supply voltage
Allowable operating frequency range 50/60 Hz ±5 Hz

Input frequency 40 to 500 Hz

Overload capacity Continuous input at 115% of maximum input, 10 s at 125% (up to 600 VAC).

Repeat accuracy

Applicable 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

Operating value

Operating time ±50 ms (at 25°C and 65% humidity, rated power supply voltage)

Conforming standards

EMC EN 60947-5-1

Safety standards

±0.5% full scale (at 25°C and 65% humidity, rated power supply voltage, DC or 50/60 Hz sine
wave input)

EN 60947-5-1
Installation environment (pollution level 2, installation category III)

UL 508 (Recognition), Korean Radio Waves Act (Act 10564),
CSA: C22.2 No.14, CCC: GB/T 14048.5

20 MΩ min.

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

2,000 VAC for one minute

Between external terminals and case
Between power supply terminals and input terminals
Between power supply terminals and output terminals
Between input terminals and 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, 0.35-mm single amplitude
10 sweeps of 5 min each in X,Y, and Z directions

K8AK-VS

3

K8AK-VS

t1

t

Set value

Input

Power supply

voltage

Relay 11-14

Relay 11-12

Alarm indicator

t: Operating time (0.1 to 30 s)

t1: Power ON lock (1 or 5 s)

Lit

Flashing

Hysteresis
(−5% to 50% of operating value)

Delay: 250 ms
(reference value)

Lit

Flashing

t1

t1: Power ON lock (1 or 5 s)

t

t: Operating time (0.1 to 30 s)

Hysteresis
(5% to 50% of operating value)

Power supply

voltage

Relay 11-14

Relay 11-12

Set value

Alarm indicator

Input

Delay: 250 ms (reference value)

Connections

Terminal Diagram

K8AK-VS2 100-240VAC

AB

Control Output

Relay output

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

B Power Supply Voltage

100 to 240 VAC 24 VAC/DC

A2

A1

A1

(No polarity)

V2

V1

A2

A1

11 12

V3

A2

C

14

A Voltage Input

VS2

V2

V1

10 V max.

V3

30 V max.

C

Relay Output

Common

11 12 14

150 V max.

VS3

V1

200 V max.

V2

300 V max.

V3

600 V max.

C

Note: 1. There is no polarity for the DC power supply input.

2. For the voltage input, you can input only from the C terminal and one other terminal.

3. Refer to Setting Ranges and Wiring Connections for information on the V1, V2, and V3 voltage input terminals.

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

Wiring Example

Single-phase
power supply

Load

4

V1 V2 V3

Power

supply voltage

A2
A1

A1 A2

C

11 12

14

Timing Charts

●Overvoltage Operation Diagram
(Output Relay Drive Method: Normally Closed)

DIP switch setting: SW3 ON.

Note: The power ON lock prevents unnecessary alarms from being

generated during the instable period when the power is first
turned on. There is no relay output during timer operation.

Power supply

AC/DC

●Undervoltage Operation Diagram
(Output Relay Drive Method: Normally Open)

DIP switch setting: SW3 OFF.

Note: The power ON lock prevents unnecessary alarms from being

generated during the instable period when the power is first
turned on. There is no relay output during timer operation.