Input impedanceRefer to Input Range on previous page.
Output relaysOne 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 humidity25% to 85% (with no condensation)
Storage humidity25% to 85% (with no condensation)
Altitude2,000 m max.
Terminal screw tightening torque0.49 to 0.59 N·m
Terminal wiring method
Case colorN1.5
Case materialPC and ABS, UL 94 V-0
WeightApprox. 150 g
MountingMounts to DIN Track.
Dimensions22.5 × 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 range85% to 110% of rated power supply voltage
Allowable operating frequency range50/60 Hz ±5 Hz
Input frequency40 to 500 Hz
Overload capacityContinuous 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 resistance100 m/s2, 3 times each in 6 directions along 3 axes
Degree of protectionTerminals: IP20
Operating value
Operating time±50 ms (at 25°C and 65% humidity, rated power supply voltage)
Conforming standards
EMCEN 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 VAC24 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.
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.
Nomenclature
K8AK-VS
Front
(See notes 1 and 2.)
Relay status indicator
(See notes 1 and 2.)
Terminal block
Power indicator
Alarm indicator
Terminal block
Voltage knob (SV)
Hysteresis knob (HYS.)
Operating time knob (T)
●Indicators
ItemMeaning
Power indicator
(PWR: Green)
Relay status indicator
(RY: Yellow)
Lit when power is being supplied.
Lit when relay is operating
Lit when there is an overvoltage or under-
voltage.
Alarm indicator
(ALM: Red)
The indicator flashes to indicate the error
status after the input has exceeded the set
value while the operating time is being
clocked.
●Setting Knobs
ItemUsage
Voltage knob (SV)
Hysteresis knob
(HYS.)
Operating time knob
(T)
Note: 1. Use either a solid wire of 2.5 mm2 maximum or a ferrule with
insulating sleeve for the terminal connection.
The length of the exposed current-carrying part inserted into
the terminal must be 8 mm or less to maintain dielectric
strength after connection.
Used to set the voltage to 10% to 100% of
maximum setting range.
Used to set the rest value to 5% to 50% of
the operating value.
Used to set the operating time to 0.1 to 30 s.
For 2.5 mm2 or
smaller solid wires
8 mm max.8 mm max.
For ferrules with
an insulation sleeve.
Recommended ferrules
Phoenix Contact
• Al 1,5-8BK (for AWG16)
• Al 1-8RD (for AWG18)
• Al 0,75-8GY (for AWG18)
2. Tightening torque: 0.49 to 0.59 N·m
5
K8AK-VS
Operation Methods
Setting Ranges and Wiring Connections
Model Setting rangeWiring connection
1 to 10 V AC/DCV1-COM
K8AK-VS2
K8AK-VS3
Connections
●Input
Connect the input between terminals V1-COM, V2-COM, or V3-COM, depending on the input
voltage.
Malfunctions may occur if the input is connected to unused terminals and the Unit will not operate
correctly.
●Power Supply
Connect the power supply to terminals A1 and A2.
●Outputs
SPDT relays are output to terminals 11, 12, and 14.
Note: Use the recommended ferrules if using twisted wires.
3 to 30 V AC/DCV2-COM
15 to 150 V AC/DCV3-COM
20 to 200 V AC/DCV1-COM
30 to 300 V AC/DCV2-COM
60 to 600 V AC/DCV3-COM
Single-phase power
Power supply
voltage
Voltage input
A1
A2
V1
V2
V3
C (COM)
Load
Signal output
14
12
Relay
signal
output
11
DIP Switch Settings
The power ON lock time, resetting method, relay drive method, and operating mode are set using the DIP switch located on the bottom of the Unit.
●DIP Switch Functions
OFF
ON
SW4
SW3
SW2
SW1
DIP switch pins
OFF ● ↑
Pin
ON ❍ ↓
Power ON
lock time
Resetting
method
Relay drive
method
Operating
mode
1 s●---------
5 s❍---------
Manual reset---●------
Automatic reset---❍------
Normally open------●---
Normally closed------❍---
Overvoltage---------●
Undervoltage---------❍
Note: All pins are set to OFF at the factory.
OFF
ON
1
234
6
K8AK-VS
22.5
90
100
72
5
K8AK-VS2
K8AK-VS3
●DIN Tracks
PFP-100N
PFP-50N
Setting Method
●Setting Voltage
The voltage knob (SV) is used to set the voltage.
The voltage can be set to 10% to 100% of the maximum
Turn the knob while there is an input to the input terminals until the alarm indicator flashes (when the set value and the input have reached the
same level.)
Use this as a guide to set the voltage.
The maximum
Example: K8AK-VS3 Using Input Terminal V3-COM
The maximum
setting range
setting range
will differ depending on the model and the input terminal.
will be 600 VAC/VDC and the setting range will be 60 to 600 V.
●Hysteresis
Hysteresis is set using the hysteresis knob (HYS.)
The setting range is 5 to 50% of the operating value.
Example: Maximum Setting of 600 VAC/VDC, Voltage Set Value (SV) of 50%, and Overvoltage Operation
Operation will be at 300 V and resetting at 270 V when the hysteresis (HYS.) is set to 10%.
●Operating Time
The operating time is set using the operating time knob (T).
The operating time can be set to between 0.1 and 30 s.
If the input voltage exceeds (or drops lower than) the voltage set value, the alarm indicator will start flashing for the set period and then stay lit.
setting range
.
Dimensions
Single-phase Voltage Relays
Optional Parts for DIN Track Mounting
4.5
15 2525
10
1,000 (500)*
±0.15
7.3
±0.3
35
2525
10
*Dimensions in parentheses are for the PFP-50N.
15 (5)*
27
1
(Unit: mm)
±0.15
7
K8AK-VS
Questions and Answers
Checking Operation
Q
Q
Overvoltages
Gradually increase the input from 80% of the set value.
The input will equal the operating value when the input
exceeds the set value and the alarm indicator starts flashing.
Operation can be checked by the relay outputs that will start
after the operating time has passed.
Undervoltage
Gradually decrease the input from 120% of the set value and
check the operation using the same method as for
overvoltage.
Example: Overvoltage Operating Mode and an Operating Time of 5 s
Note: K8AK-VS@ output relays are normally operative.
Set value
Input voltage
Alarm indicator
Relay output
Connection Diagram
200 VAC
Variable
autotransformer
0 to 300 V
V
Flashing
5 s
Input terminals
Power supply
Lit
A1
A2
How to Measure the Operating Time
Q
Q
Overvoltage
Change the input suddenly from 0% to 120% of the set value
and measure the time until the Unit operates.
Undervoltage
Change the input suddenly from 120% to 0% of the set value
and measure the time until the Unit operates.
±
C 200 V
Cycle counter
8
K8AK-VS
Safety Precautions
Be sure to read the precautions for all models in the website at the following URL: http://www.ia.omron.com/.
Warning Indications
Indicates a potentially hazardous situation
which, if not avoided, will result in minor or
WARNING
CAUTION
Precautions for Safe
Use
Precautions for
Correct Use
moderate injury, or may result in serious
injury or death. Additionally there may be
significant property damage.
Indicates a potentially hazardous situation
which, if not avoided, may result in minor or
moderate injury or in property damage.
Supplementary comments on what to do or
avoid doing, to use the product safely.
Supplementary comments on what to do or
avoid doing, to prevent failure to operate,
malfunction, or undesirable effects on
product performance.
Meaning of Product Safety Symbols
Used to warn of the risk of electric shock under
specific conditions.
Used for general prohibitions for which there is no
specific symbol.
Used to indicate prohibition when there is a risk of
minor injury from electrical shock or other source if
the product is disassembled.
WARNING
Electrical shock may occasionally cause serious injury.
Confirm that the input voltage is OFF before starting any
wiring work and wire all connections correctly.
CAUTION
Electrical shock may cause minor injury.
Do not touch terminals while electricity is being supplied.
There is a risk of minor electrical shock, fire, or device failure.
Do not allow any pieces of metal, conductors, or cutting chips
that occur during the installation process to enter the product.
Explosions may cause minor injuries. Do not use the product
in locations with inflammable or explosive gases.
There is a risk of minor electrical shock, fire, or device failure.
Do not disassemble, modify, repair, or touch the inside of the
product.
Loose screws may cause fires. Tighten terminal screws to the
specified torque of 0.49 to 0.59 N·m.
Used for general mandatory action precautions for
which there is no specified symbol.
Use of excessive torque may damage the terminal screws.
Tighten terminal screws to the specified torque of 0.49 to
0.59 N·m.
Use of the product beyond its life may result in contact welding
or burning. Make sure to consider the actual operating
conditions and use the product within its rated load and
electrical life count. The life of the output relay varies
significantly with the switching capacity and switching
conditions.
9
K8AK-VS
AB
Precautions for Safe Use
1. Do not use or store the product in the following locations.
• Locations subject to water or oil
• Outdoor locations or under direct sunlight
• Locations subject to dust or corrosive gases (particularly
sulfurizing gases, ammonia, etc.)
• Locations subject to rapid temperature changes
• Locations prone to icing and dew condensation
• Locations subject to excessive vibration or shock
• Locations subject to wind and rain
• Locations subject to static electricity and noise
• Habitats of insects or small animals
2. Use and store the product in a location where the ambient
temperature and humidity are within the specified ranges. If
applicable, provide forced cooling.
3. Mount the product in the correct direction.
4. Check terminal polarity when wiring and wire all connections
correctly. The power supply terminals do not have polarity.
5. Do not wire the input and output terminals incorrectly.
6. Make sure the power supply voltage and loads are within the
specifications and ratings for the product.
7. Make sure the crimp terminals for wiring are of the specified size.
8. Do not connect anything to terminals that are not being used.
9. Use a power supply that will reach the rated voltage within 1
second after the power is turned ON.
10.Keep wiring separate from high voltages and power lines that
draw large currents.
Do not place product wiring in parallel with or in the same path as
high-voltage or high-current lines.
11.Do not install the product near equipment that generates high
frequencies or surges.
12.The product may cause incoming radio wave interference. Do not
use the product near radio wave receivers.
13.Install an external switch or circuit breaker and label it clearly so
that the operator can quickly turn OFF the power supply.
14.Make sure the indicators operate correctly. Depending on the
application environment, the indicators may deteriorate
prematurely and become difficult to see.
15.Do not use the product if it is accidentally dropped. The internal
components may be damaged.
16.Be sure you understand the contents of this catalog and handle
the product according to the instructions provided.
17.Do not install the product in any way that would place a load on it.
18.When discarding the product, properly dispose of it as industrial
waste.
19.When using the product, remember that the power supply
terminals carry a high voltage.
20.The product must be handled only by trained electrician.
21.Prior to operation, check the wiring before you supply power to
the product.
22.Do not install the product immediately next to heat sources.
23.Perform periodic maintenance.
Precautions for Correct Use
Observe the following operating
methods to prevent failure and
malfunction.
1. Use the power supply voltage, input power, and other power
supplies and converters with suitable capacities and rated
outputs.
2. Use a precision screwdriver or similar tool to adjust the setting
knobs.
3. Do not use the product in circuits with waveform distortion. Error
will be large due to waveform distortion.
4. Error will be large if the product is used for thyristor or inverter
control.
5. To reduce the error in the setting knob, always turn the setting
knob from the minimum setting toward the maximum setting.
6. When cleaning the product, do not use thinners or solvents. Use
commercial alcohol.
Correct Mounting Direction, Mounting,
and Removing
• Mounting to DIN Track
1. Attach the product to the DIN Track with the tab at the top and
the hooks at the bottom.
2. Push the product onto the Track until the hooks lock into place.
• Removing from the DIN Track
Pull down on the bottom hook with a flat-blade screwdriver and lift
up on the product.
Applicable DIN Tracks:
PFP-100N (100 cm)
PFP-50N (50 cm)
10
Adjusting the Setting Knobs
• Use a screwdriver to adjust the setting knobs. The knobs have a
stopper that prevents them from turning beyond the full right or left
position. Do not force a knob beyond these points.
Setting knob
Terms and Conditions Agreement
Read and understand this catalog.
Please read and understand this catalog before purchasing the products. Please consult your OMRON representative if you have
any questions or comments.
Warranties.
(a) Exclusive Warranty. Omron’s exclusive warranty is that the Products will be free from defects in materials and workmanship
for a period of twelve months from the date of sale by Omron (or such other period expressed in writing
by Omron). Omron disclaims all other warranties, express or implied.
(b) Limitations. OMRON MAKES NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, ABOUT
NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OF THE
PRODUCTS. BUYER ACKNOWLEDGES THAT IT ALONE HAS DETERMINED THAT THE PRODUCTS WILL
SUITABLY MEET THE REQUIREMENTS OF THEIR INTENDED USE.
Omron further disclaims all warranties and responsibility of any type for claims or expenses based on infringement by the Products
or otherwise of any intellectual property right. (c) Buyer Remedy. Omron’s sole obligation hereunder shall be, at Omron’s election,
to (i) replace (in the form originally shipped with Buyer responsible for labor charges for removal or replacement thereof) the
non-complying Product, (ii) repair the non-complying Product, or (iii) repay or credit Buyer an amount equal to the purchase price
of the non-complying Product; provided that in no event shall Omron be responsible for warranty, repair, indemnity or any other
claims or expenses regarding the Products unless Omron’s analysis confirms that the Products were properly handled, stored,
installed and maintained and not subject to contamination, abuse, misuse or inappropriate modification. Return of any Products by
Buyer must be approved in writing by Omron before shipment. Omron Companies shall not be liable for the suitability or
unsuitability or the results from the use of Products in combination with any electrical or electronic components, circuits, system
assemblies or any other materials or substances or environments. Any advice, recommendations or information given orally or in
writing, are not to be construed as an amendment or addition to the above warranty.
See http://www.omron.com/global/ or contact your Omron representative for published information.
Limitation on Liability; Etc.
OMRON COMPANIES SHALL NOT BE LIABLE FOR SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
LOSS OF PROFITS OR PRODUCTION OR COMMERCIAL LOSS IN ANY WAY CONNECTED WITH THE PRODUCTS,
WHETHER SUCH CLAIM IS BASED IN CONTRACT, WARRANTY, NEGLIGENCE OR STRICT LIABILITY.
Further, in no event shall liability of Omron Companies exceed the individual price of the Product on which liability is asserted.
Suitability of Use.
Omron Companies shall not be responsible for conformity with any standards, codes or regulations which apply to the
combination of the Product in the Buyer’s application or use of the Product. At Buyer’s request, Omron will provide applicable
third party certification documents identifying ratings and limitations of use which apply to the Product. This information by itself is
not sufficient for a complete determination of the suitability of the Product in combination with the end product, machine, system,
or other application or use. Buyer shall be solely responsible for determining appropriateness of the particular Product with
respect to Buyer’s application, product or system. Buyer shall take application responsibility in all cases.
NEVER USE THE PRODUCT FOR AN APPLICATION INVOLVING SERIOUS RISK TO LIFE OR PROPERTY OR IN LARGE
QUANTITIES WITHOUT ENSURING THAT THE SYSTEM AS A WHOLE HAS BEEN DESIGNED TO ADDRESS THE RISKS,
AND THAT THE OMRON PRODUCT(S) IS PROPERLY RATED AND INSTALLED FOR THE INTENDED USE WITHIN THE
OVERALL EQUIPMENT OR SYSTEM.
Programmable Products.
Omron Companies shall not be responsible for the user’s programming of a programmable Product, or any consequence thereof.
Performance Data.
Data presented in Omron Company websites, catalogs and other materials is provided as a guide for the user in determining
suitability and does not constitute a warranty. It may represent the result of Omron’s test conditions, and the user must correlate it
to actual application requirements. Actual performance is subject to the Omron’s Warranty and Limitations of Liability.
Change in Specifications.
Product specifications and accessories may be changed at any time based on improvements and other reasons. It is our practice
to change part numbers when published ratings or features are changed, or when significant construction changes are made.
However, some specifications of the Product may be changed without any notice. When in doubt, special part numbers may be
assigned to fix or establish key specifications for your application. Please consult with your Omron’s representative at any time to
confirm actual specifications of purchased Product.
Errors and Omissions.
Information presented by Omron Companies has been checked and is believed to be accurate; however, no responsibility is
assumed for clerical, typographical or proofreading errors or omissions.
OMRON Corporation Industrial Automation Company
Tokyo, JAPAN
Contact: www.ia.omron.com
Regional Headquarters
OMRON EUROPE B.V.
Wegalaan 67-69-2132 JD Hoofddorp
The Netherlands
Tel: (31)2356-81-300/Fax: (31)2356-81-388
OMRON ASIA PACIFIC PTE. LTD.
No. 438A Alexandra Road # 05-05/08 (Lobby 2),
Alexandra Technopark,
Singapore 119967
Tel: (65) 6835-3011/Fax: (65) 6835-2711
OMRON ELECTRONICS LLC
One Commerce Drive Schaumburg,
IL 60173-5302 U.S.A.
Tel: (1) 847-843-7900/Fax: (1) 847-843-7787
OMRON (CHINA) CO., LTD.
Room 2211, Bank of China Tower,
200 Yin Cheng Zhong Road,
PuDong New Area, Shanghai, 200120, China CSM_2_7_0619
Tel: (86) 21-5037-2222/Fax: (86) 21-5037-2200