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flashing. Operation can be checked by the relay output that
will start after the operating time has passed.
Undervoltage
Gradually decrease the input from 120% of the setting and
check the operation using the same method as for
overvoltage.
Example: For monitoring mode set to three-phase three-wire
monitoring, a rated voltage of 200 V, and an operating time
of 5 s.
Note: K8AB-PW@ output relays are normally operative.
Connection Diagram
How to Measure the Operating Time
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.
Operating Time
Adjust the slide resistor so that the voltage applied to the
K8AB terminals is 120% of the overvoltage set value or
80% of the undervoltage set value when the auxiliary relay
operates in a test circuit. Close the switch and use the
cycle counter to measure the operating time.
Connection Diagram
Operating Adjustment Knobs
Use a screwdriver to turn the knobs. There is a stopper to
prevent the knob from turning any further once it has been
turned completely to the left or right. Do not force the knob
past these limits.
Overvoltage Detection When Only One Phase Exceeds
the Overvoltage Threshold
The K8AB monitors each of the three-phase voltages. This
means an overvoltage is detected if even only one phase
exceeds the threshold value. The same applies to
Undervoltages.
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.
• Universal-input support for thermocouple or Pt100 sensor input.