258BM-240VAC-400

258BM-240VAC-400

The Model 258BM-400 3-Phase Monitor offers essential protection for industrial applications. This device detects critical conditions such as phase loss, low voltage, and phase reversal, safeguarding connected equipment. Operating at 208/240VAC nominal with a 400Hz frequency, it provides reliable monitoring. Its 50ms drop out response time ensures prompt action upon fault detection. With a repeat accuracy of ± 0.1% of set point, consistent performance is maintained. The unit's robust design includes an ABS plastic cover and a wide operating temperature range of -20° to +131° F, ensuring durability in diverse environments. This monitor is a practical solution for maintaining system integrity.

The Model 258 continuously monitors 3-phase power lines for abnormal
conditions. When properly adjusted, the Model 258 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 258 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.

Out of stock

Specifications

Reset TypeMANUAL Reset
Nominal AC voltage (phase to phase)208/240VAC
Case ColorRed
Adjustment range160-240VAC
Frequency400Hz
Power consumption2.4W
Protection FeatureDetects phase loss, low voltage, phase reversal
WarrantyFive year unconditional warranty
Transient protection2500VAC for 10ms
Repeat accuracy± 0.1% of set point (fixed conditions)
Response time50ms drop out
Dead bandApprox. 2%
Output contactsSPDT 10 amps at 240VAC resistive
Expected relay life (Mechanical)10 million operations
Expected relay life (Electrical)100,000 operations at rated load
Operating temperature-20° to +131° F
Humidity tolerance0-97% w/o condensation
Enclosure materialABS plastic cover
Mounting8-pin socket (**sold separately)
Agency approvalsUL Recognized* and CSA Certified

FAQs

What specific electrical conditions does the Model 258BM-400 monitor for?
The Model 258BM-400 detects phase loss, low voltage, and phase reversal to protect connected equipment.
What are the operating voltage and frequency specifications for this 3-phase monitor?
This monitor operates at a nominal AC voltage of 208/240VAC (phase to phase) with an adjustment range of 160-240VAC and a frequency of 400Hz.
What is the expected operational lifespan of the relay contacts in the Model 258BM-400?
The relay contacts have an expected mechanical life of 10 million operations and an electrical life of 100,000 operations at rated load.