4

Three-phase Voltage Relay

K8AB-PW

Cat. No. N148-E1-01

Connections

■ Wiring Diagram

Overvoltage and Undervoltage Operation Diagram

Note: 1. The K8AB-PW output relay is normally operative.

2. 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

■ Front

Indicators

Setting Knobs

T

T1

T

L1

L2

L3

Hysteresis: Fixed at 5%

Hysteresis: Fixed at 5%

T: Operating time (0.1 to 30 s)

T1: Power ON lock (1 s or 5 s)

Flashing

Lit

Flashing

Lit

Overvoltage alarm indicator

Undervoltage alarm indicator

Overvoltage relay

Undervoltage relay

Undervoltage setting value

Overvoltage

setting value

Input

T: Operating time (0.1 to 30 s)

Input

Output

Output

NL1 L2 L3

N

L1

L2

L3

14

12

11

24

22

21

Over-

voltage

alarm

Under-

voltage

alarm

Load

The power

supply is

shared with

the rated in-

put voltage.

Power indicator

Relay status indicator

Overvoltage knob (OVER)

Undervoltage knob (UNDER)

Operating time knob (T)

Alarm indicator

Item

Meaning

Power indicator (PWR: Green)

Lit when power is being

supplied.

Relay status indicator (RY: Yellow) Lit when relay is operating

(normally lit).

Alarm

indicator

(ALM: Red)

Overvoltage: Red

The indicator flashes to indicate

the error status after the

overvoltage has exceeded the

threshold value while the

operating time is being clocked.

Undervoltage: Red The indicator flashes to indicate

the error status after the

undervoltage has exceeded the

threshold value while the

operating time is being clocked.

Item

Usage

Overvoltage knob (OVER)

Used to set the voltage to

−30% to 25%

of the rated input voltage.

Undervoltage knob

(UNDER)

Used to set the voltage to

−30% to 25%

of the rated input voltage.

Operating time knob (T)

Used to set the operating time to 0.1 to

30 s.