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Industrial Automation

Industrial Automation

K8AK-AS

Single-phase Current Relay

K8AK-AS

Ideal for Current Monitoring for Industrial Facilities and Equipment. Monitor for overcurrents or undercurrents.

Input Range

Model Range *1 Connection
terminal
Setting
range
Input
impedance
Input type Overload
capacity
K8AK-AS1 0 to 20 mA
AC/DC
I1-COM 2 to 20 mA AC/DC,
10 to 100 mA AC/
DC, 50 to 500 mA
AC/DC
Approx. 5 Ω Direct input Continuous input at
120% of maximum
input 1 s at 150%
0 to 100 mA
AC/DC
I2-COM Approx. 1 Ω Direct input
0 to 500 mA
AC/DC
I3-COM Approx. 0.2 Ω Direct input
K8AK-AS2 0 to 1 A
AC/DC
I1-COM 0.1 to 1 A AC/DC,
0.5 to 5 A AC/DC,
0.8 to 8 A AC/DC
Approx. 0.12 Ω Direct input
or
commercially
available CT
0 to 5 A
AC/DC
I2-COM Approx. 0.02 Ω
0 to 8 A
AC/DC
I3-COM Approx. 0.02 Ω Direct input
K8AK-AS3 0 to 100 A
AC
I2-COM 10 to 100 A AC *2,
20 to 200 A AC *2
- OMRON CT Continuous input at
120% with an OMRON
CT (K8AC-CT200L).
30 s at 200%
1 s at 600%
* CT capacity on
primary side.
0 to 200 A
AC
I3-COM - OMRON CT

*1 The range is selected using connected terminals.
*2 The K8AK-AS3 is designed to be used in combination with an OMRON K8AC-CT200L Current Transformer (CT).
      (Direct input is not possible.)

Ratings

Power supply
voltage
Isolated power supply 24 VAC/DC
100 to 240 VAC
Power consumption 24 VAC/DC: 2.0 VA/1.1 W max.
100 to 240 VAC: 4.6 VA max.
Operating value setting range (SV) 10% to 100% of the maximum value of the setting range
K8AK-AS1:
2 to 20 mA AC/DC
10 to 100 mA AC/DC
50 to 500 mA AC/DC
K8AK-AS2:
0.1 to 1 A AC/DC (Compatible with commercially available CTs.)
0.5 to 5 A AC/DC (Compatible with commercially available CTs.)
0.8 to 8 A AC/DC
K8AK-AS3:
When used with the OMRON CT (K8AC-CT200L).
10 to 100 A AC
20 to 200 A AC
Operating value 100% operation at set value
Reset value setting range (HYS.) 5% to 50% of operating value
Reset method Manual reset/automatic reset (switchable)
Note: Manual reset: Turn OFF power supply for 1 s or longer.
Operating time setting range (T) 0.1 to 30 s
Startup lock time setting range
(LOCK)
Note: Enabled only for overcurrent
operation.
0 to 30 s
(The startup lock timer starts when the input has reached approximately
30% or more of the set value.)
Note: Enabled only for overcurrent operation.
Indicators Power (PWR): Green, Relay output (RY): Yellow, Alarm outputs (ALM): Red
Input impedance Refer to Input Range on this page.
Output relays One SPDT relay (NO/NC switched using DIP switch.)
Output relay ratings 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
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 Nm
Terminal wiring method Recommended wire
Solid wire: 2.5 mm2
Twisted wires: AWG16, AWG18
Note: 1. Ferrules with insulating sleeves must be used with twisted wires.
Note: 2. Two wires can be twisted together.
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
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)

Specifications

Allowable operating voltage
range
85% to 110% of power supply voltage
Allowable operating
frequency range
50/60 Hz ±5 Hz
Input frequency range K8AK-AS1 and K8AK-AS2: DC input or AC input (45 to 65 Hz)
K8AK-AS3: AC input (45 to 65 Hz)
Overload capacity K8AK-AS1 and K8AK-AS2: Continuous input at 120% of maximum input, 1 s at 150%
K8AK-AS3: Continuous input at 120%, 30 s at 200%, and 1 s at 600% with an OMRON
CT (K8AC-CT200L)
Note: Overload capacity of primary side of CT.
Repeat
error
Operating value ±0.5% full scale (at 25°C and 65% humidity, rated power supply voltage, DC or 50/60
Hz sine wave input)
Operating time ±50 ms (at 25°C and 65% humidity, rated power supply voltage)
Applicable
standards
Conforming
standards
EN 60947-5-1
Installation environment (pollution level 2, installation category III)
EMC EN 60947-5-1
Safety standards UL 508 (Recognition), Korean Radio Waves Act (Act 10564), CSA: C22.2 No.14,
CCC: GB/T 14048.5
Insulation resistance 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
Dielectric strength 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
Noise immunity 1,500 V power supply terminal common/normal mode
Square-wave noise of ±1 μs/100 ns pulse width with 1-ns rise time
Vibration resistance Frequency 10 to 55 Hz, 0.35-mm single amplitude
10 sweeps of 5 min each in X, Y, and Z directions
Shock resistance 100 m/s2, 3 times each in 6 directions along 3 axes
Degree of protection Terminals: IP20

Relationship of Mounting Distance between K8AK-AS Relays and Input Current (Reference Values)

AS (I3 terminal) The following diagram shows the relationship between the mounting distances and the input current. If the relay is used with an input current that exceeds these values, the temperature of the K8AK may rise and shorten the life of the internal components.

K8AK-AS Specifications 5