Omron K8AB-TH DATASHEET

Temperature Monitoring Relay

K8AB-TH

Compact and Slim Relay Ideal for
Temperature Alarms and Monitoring

• Excessive temperature increases can be prevented and abnormal
temperatures can be monitored.

• Temperature monitoring in slim design with a width of just 22.5 mm.

• Simple function settings using DIP switch.

• Multi-input support for thermocouple or Pt100 sensor input.

• Selectable output relay: Non-fail safe/fail safe.

• Alarm status identification with LED indicator.

• CE Marking
UL/CSA certification pending.

Features

• This Temperature Monitoring Relay was designed specially for

monitoring abnormal temperatures to prevent excessive
temperature increase and to protect equipment.

• A relay capacity of 3 A at 250 VAC (resistive load) is provided.
An output latch function is also supported.

• Settings can be made and functions can be selected using the DIP
switch.

• Reduce the number of models by using multi-input support for
thermocouple or Pt100 sensor input.

Model Number Structure

■ Model Number Legend

K8AB-TH1@@

1243

1. Basic Model

K8AB: Measuring and Monitoring Relay

2. Function

TH1: Temperature Monitoring Relay

Ordering Information

Selecting Functions and Modes

• The following settings are provided: alarm mode (upper limit/lower

limit), enable/disable latch,
setting protection.

Terminal Wiring with Ferrules

• Wire with 2

3. Setting Range

1: Low-temperature range (0 to 399

2: High-temperature range (0 to 1800

4. Output Form

S: One SPDT relay output

× 2.5 mm

1

°C)

increments of 10

°C/°F, relay output non-fail safe/fail safe,

2

solid wire or 2 × 1.5 mm2 wiring ferrules.

°C: setting in increments of

°C)

°C max.: setting in

■ List of Models

Temperature Monitoring Relay Input type Temperature

Thermocouple/
Pt100

Thermocouple 0 to 1,700

Note: Refer to page 3 for setting ranges.

setting range

°C/°F1°C/°F 100 to 240 VAC K8AB-TH11S 100-240VAC

0 to 399

0 to 3,200

°C
°F

Setting unit Supply voltage Model

24 VAC/VDC K8AB-TH11S 24VAC/VDC

°C/°F (See note.) 100 to 240 VAC K8AB-TH12S 100-240VAC

10

24 VAC/VDC K8AB-TH12S 24VAC/VDC

Temperature Monitoring Relay K8AB-TH 1

Specifications

■ Ratings

Item Power supply voltage 100 to 240 VAC 50/60 Hz 24 VAC 50/60 Hz or 24 VDC

Allowable voltage range 85% to 110% of power supply voltage

Power consumption 5 VA max. 2 W max. (24 VDC), 4 VA max. (24 VAC)

Sensor inputs K8AB-TH11S Thermocouple: K, J, T, E; Platinum-resistance thermometer: Pt100

K8AB-TH12S Thermocouple: K, J, T, E, B, R, S, PLII

Output relay One SPDT relay (3 A at 250 VAC, resistive load)

External inputs
(for latch setting)

Setting method Rotary switch setting (set of three switches)

Indicators Power (PWR): Green LED, Relay output (ALM): Red LED

Other functions Alarm Mode (upper limit/lower limit), non-fail safe/fail safe selection, output latch, setting protection, temperature

Ambient operating temperature

Ambient operating humidity Relative humidity: 25% to 85%

Storage temperature

■ Characteristics

Setting accuracy ±2.0% of full scale

hysteresis width 2

Output relay Resistive load 3 A at 250 VAC (cos

Sampling cycle 500 ms

Insulation resistance 20 M

Dielectric strength 2,000 VAC 50/60 Hz for 1 min between charged terminals of different polarity

Vibration resistance

Shock resistance

Weight 130 g

Degree of protection IP20

Memory protection Non-volatile memory (number or writes: 200,000)

Safety
Standards

EMC EMI: EN 61326

Terminal screw tightening torque 0.54 to 0.55 N·m

Crimp terminals

Case color Munsell 5Y8/1 (ivory)

Case material ABS resin (self-extinguishing resin)

Mounting Mounted to DIN Track or with M4 screws

Dimensions 22.5

Contact input ON: 1 k

Non-contact input ON residual voltage: 1.5 V max., OFF leakage current: 0.1 mA max.

Inductive load 1 A at 250 VAC (cos

Minimum load 10 mA at 5 VDC

Maximum contact voltage 250 VAC

Maximum contact current 3 A AC

Maximum switching capacity 1,500 VA

Mechanical life 10,000,000 operations

Electrical life Make: 50,000 times, Break: 30,000 times

Approved standards EN 61010-1

Application standards EN 61326 and EN 61010-1 (pollution level 2, overvoltage category II)

Ω max., OFF: 100 kΩ min.

Leakage current: Approx. 10 mA

unit

°C/°F

−10 to 55°C (with no condensation or icing)

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

°C

φ = 1), 3 A at 30 VDC (L/R = 0 ms)

φ = 0.4), 1 A at 30 VDC (L/R = 7 ms)

Ω (at 500 V) between charged terminals and exposed uncharged parts
Ω (at 500 V) between any charged terminals (i.e., between input, output, and power supply terminals)

20 M
20 M

Ω (at 500 V) between contacts (open)

2

Vibration of 10 to 55 Hz and acceleration of 50 m/s

2

(100 m/s2 for relay contacts) 3 times each in 6 directions in X, Y, and Z directions

150 m/s

Radiation Interference Field Intensity: EN 55011 Group 1 Class A
Noise Terminal Voltage: EN 55011 Group 1 Class A
EMS: EN 61326
Immunity ESD: EN 61000-4-2: 4 kV contact discharge (level 2)

Immunity RF: EN 61000-4-3: 10 V/m, amplitude-modulated

Immunity Burst: EN 61000-4-4: 2 kV power line (level 3)

Immunity Conducted Disturbance: EN 61000-4-6: 3 V (0.15 to 80 MHz) (level 3)
Immunity Surge: EN 61000-4-5: 1 kV line-to-line: power line, output line

Commercial Frequency
Immunity Magnetic Field: EN 61000-4-8: 30 A/m (50Hz) continuous time
Immunity Voltage Dip/Interrupting: EN 61000-4-11: 0.5 cycle, 100% (rated voltage)

2

Two solid wires of 2.5 mm

× 100 × 90 mm (W × D × H)

or two ferrules of 1.5 mm2 with insulation sleeves can be tightened together.

for 5 min with 10 sweeps each in X, Y, and Z directions

8 kV air discharge (level 3)

(80 MHz to 1 GHz, 1.4 GHz to 2 GHz) (level 3)

2 kV output line (relay output) (level 4)
1 kV measurement line and I/O signal lines (level 4)

(relay output) (level 2)
2 kV line-to-ground: power line, output line
(relay output) (level 3)

2 Temperature Monitoring Relay K8AB-TH

■ Setting Ranges

K8AB-TH11S

Centigrade

Input KJTEPt100

500

399 399 399 399 399

Setting
tempera­ture range

Minimum setting
increment

Fahrenheit

Setting
tempera­ture range

Minimum setting
increment

K8AB-TH12S

Centigrade

Setting
tempera­ture range

Minimum setting
increment

400
300
200
100

0

00000

Input KJTEPt100

500

399 399 399 399 399

400
300
200
100

0

00000

Input KJTEBRSPLII

1,800
1,700
1,600
1,500
1,400

1,300 1,300

1,300
1,200
1,100
1,000

900
800
700
600
500
400
300
200
100

0

0000 000

850

1°C

1°F

400

600

10°C

1,800

100

1,700 1,700

Fahrenheit

Setting
tempera­ture range

Minimum setting
increment

Input KJTEBRSPLII

3,200
3,100
3,000
2,900
2,800
2,700
2,600
2,500
2,400

2,300 2,300

2,300
2,200
2,100
2,000
1,900
1,800
1,700
1,600
1,500
1,400
1,300
1,200
1,100
1,000

900
800
700
600
500
400
300
200
100

0

1,500

1,100

700

0000 000

3,200

3,000 3,000

300

10°F

Temperature Monitoring Relay K8AB-TH 3