Description

True RMS Measurement: Provides accurate voltage monitoring for dependable protection.
8-Level Voltage Selection: Easily adjustable via a user-friendly knob.
Wide Frequency Range: Measures 45Hz-65Hz, compatible with various power systems.
High Accuracy: Voltage measurement precision of less than 1%.
LED Indicators: Clear visual feedback on relay status for quick diagnostics.
Versatile Models: Options (21-26) with combinations of overvoltage, undervoltage, asymmetry, delay, and phase protection.

Function code	Over- voltage	Under- voltage	Asymmetry	OFF delay Phase time	Phase sequence	Phase failure
21					○	●
22	5%…25%,OFF	OFF,-25%…-5%		0.1s…30s	●	●
23	5%…25%,OFF	OFF,-25%…-5%	8%	0.1s…30s	●	●
24	5%…25%,OFF	OFF,-25%…-5%	5%…20%,OFF	2s	●	●
25			5%…20%	0.1s…30s	●	●
26	15%	-15%	8%	2s	●	●

Note:

● the function is available

○ the function is adjustable

Parameter	3P3W	3P4W
Function	Monitoring 3-phase voltage
Monitoring terminals	L1-L2-L3	L1-L2-L3-N
Supply terminals	L1-L2
Voltage range	380-400-415-440-480(P-P)	220-230-240-254-277(P-N)
Rated supply frequency	45Hz-65Hz
Measuring range	260V-576V	150V-332V
Threshold adjustment voltage	5%-25%of Un selected or OFF The Max “U>” for Un 277V or 480V shall not exceed 20%
Adjustment threshold	5%-20% or OFF
Hysteresis	2%
Phase failure value	70% of Un selected
OFF delay time(Tt)	Adjustable 0.1s-30s,10%
Measurement error	≤1%
Delay at power up(Tr)	0.5s
Knob setting accuracy	10% of scale value
Output indication	Green LED
Fault indication	Red LED
Reset time	1s
Output	2×SPDT
Current rating	8A/AC1
Switching voltage	250VAC/24VDC
Min.breaking capacity DC	500mW
Temperature coefficient	0.05%/°C,at=20°C(0.05%°F,at=68°F)
Mechanical life	1×10⁷
Electrical life(AC1)	1×10⁵