3-Phase Monitor

 

• Detects Phase Loss, Low Voltage and Phase Reversal
• 50Hz and 60Hz versions
• Automatic Reset

 

Description

The Model 252 3-Phase Monitor continuously monitors 3-phase power lines for abnormal conditions. When properly adjusted, the Model 252 will detect phase loss on a loaded motor even when regenerated voltage is present.

The device consists of a solid-state voltage and phase-angle sensing circuit, driving an electromechanical relay with one SPDT and one SPST contact. When correct voltage and phase rotation are applied, the internal relay will energize. A fault condition will de-energize the relay. When the fault is corrected the Model 252 will automatically reset.

The Model 252 does not require a neutral connection and can be used with Wye or Delta systems. Four versions cover 120V, 208/240V and 480V, 60Hz, and 380V, 50Hz. Adjustment ranges are sufficiently wide to allow for proper adjustment to existing conditions. Two LED indicator are provided to aid in adjustment and system troubleshooting.

 

Specifications

Model	B252B	252B	A252B	EX252B
Nominal AC Voltage	120VAC	208/240VAC	480VAC	380VAC
Adjustment Range	85-120VAC	160-240VAC	380-480VAC	300-380VAC
Frequency	60Hz			50Hz
Power Consumption	0.25W	0.50W	1.5W	1.25W
Transient Protection	2500V for 10ms
Repeat Accuracy	0.1% of set point (fixed conditions)
Response Time	0.05 seconds
Reset Time	0.05 seconds
Reset Type	Automatic
Dead Band	2%
Output Contacts	1 - SPDT 1 - SPST (N.O.)
Contact Rating	5A at 115VAC resistive
Expected Relay Life	Mech: 10 million operations Elec: 100,000 at rated load
Operating Temp	-20° to 131° F
Humidity Tolerance	97% w/o condensation
Enclosure Material	ABS plastic
Mounting	8-pin socket (*order separately)
Weight	5 oz.
Agency Approvals	UL Recognized (U.S. & Canadian)

Downloads

Document	File Type	File Size	Download
Model 252 Datasheet	PDF	475 KB

© 2023 Relay Specialties, Inc.
17 Raritan Road, Oakland, NJ 07436 | 800-526-5376
Created By: G.Dezines