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TIME MARK CORP INFO A257B 480 VAC SPDT 3-Phase Monitor

MFG Part #: A257B
Brand Name: Time Mark
UPC: 66291700169
Online Part #: 152547


The Model 257 continuously monitors 3-phase power lines for abnormal conditions. When properly adjusted, the Model 257 monitor will detect phase loss on a loaded motor even when regenerated voltage is present. This device consists of a solid-state voltage and phase-angle sensing circuit, driving an electromechanical relay. 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 monitor will automatically reset (a manual reset version is also available). The Model 257 does not require a neutral connection and can be used with Wye or Delta systems. Voltage ranges are sufficiently wide to allow for proper adjustment to existing conditions. Both TRIP and NORM condition indicators are provided to aid in adjustment and system trouble-shooting. (mfg. sku: 98083703)

Detailed Information

Make and Model

Online Part #: 152547
MFG Name: Time Mark


Measuring Range: 480 VAC
Mounting: 8-pin
Type: Product, 3-Phase Monitor
Standards: CSA and UL
Enclosure: ABS Plastic
Contact Configuration: SPDT
Phase: 3
Operating Temperature: -20 to +131 F
Connection: 8-pin
Brand Name: Time Mark
Voltage Rating: 480 VAC
Contact Rating: 10A 240 VAC
Size: 3.52in X 2.44in X 1.75in

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