20VB

20VB

The MODEL 20VB 3-Phase Voltage Band Monitor provides critical protection for industrial systems. This device monitors phase loss, phase reversal, over/under voltage, and voltage unbalance across an operating voltage range of 190-480 VAC. Its adjustable trip delays, ranging from 1 to 30 seconds, and restart delays, from 1 to 500 seconds, allow for precise system integration and minimize nuisance tripping. The fail-safe relay operation ensures equipment safety by dropping contacts upon fault detection or power loss, enhancing operational reliability. Compatible with both Wye and Delta systems, it does not require a neutral connection, simplifying installation and reducing wiring complexity. With SPDT 10A at 240VAC resistive output contacts, it integrates seamlessly into control circuits. This monitor is designed for reliable performance in diverse industrial environments, offering a 5-year unconditional warranty for sustained operational integrity and peace of mind.

A microcontroller-based universal 3-phase voltage band monitor for
protecting 3-phase motors of any size from abnormal power conditions.
The Model 20VB can detect under voltage, over voltage, voltage
unbalance, reverse phase, and single-phasing even when regenerated
voltage is present. Status of the 3-phase system is indicated by LEDs.
The Model 20VB is UL Recognized in the U.S. and Canada. Relay operation
is fail-safe, i.e. the SPDT output contacts drop out when a fault
condition or loss of power occurs. Under and over voltage trip points
are both adjustable. The under voltage adjustment has two scales,
185-240VAC and 370-480VAC. The over voltage adjustment also has two
scales, 208-264VAC and 416-528VAC. The Model 20VB will auto-range to the
appropriate scale. A trip delay adjustment for preventing nuisance
tripping during power fluctuations and a restart delay adjustment for
preventing short cycling in compressor applications have also been
provided. Voltage unbalance trip point is fixed at 6%. The Model 20VB
does not require a neutral connection and can be used on either Wye or
Delta systems. Operating power for the Model 20VB is drawn from phases A
and B.

Out of stock

Specifications

Operating Voltage190-480 VAC
Frequency50/60Hz
Type of MeasurementRMS
Auto RangesYes
Under Voltage Trip Range185-480VAC
Under Voltage ResetTrip setting +3%
Over Voltage Trip Range208-528VAC
Over Voltage ResetTrip setting -3%
Voltage Unbalance Trip6%, Fixed
Voltage Unbalance Reset5% Fixed
Trip Delay (Over, Under, & Unbalanced)1-30 sec., adjustable
Trip Delay (Single-Phasing Faults)1 sec., fixed
Trip Delay (Unbalance > 15%)1 sec., fixed
Restart Delay1-500 sec., adjustable
Restart Delay Reset TypeAutomatic
Output ContactsSPDT 10A at 240VAC resistive
Power Consumption3W
Operating Temperature-20° to +140° F
Humidity Tolerance0-97% w/o condensation
Terminal Torque3.5 in. lbs. maximum
Wire TypeStranded or solid 14-26 AWG, 1/terminal
Enclosure MaterialNORYL plastic
MountingDIN Rail or Surface Mount
Additional Options/SG = Silver with Gold Flash Contacts
Agency ApprovalUL Recognized (U.S. and Canada) (For use in a Pollution Degree 2 Environment)
Monitored ConditionsPhase Loss, Phase Reversal, Over/Under Voltage and Voltage Unbalance
Relay OperationFail-safe, i.e. the SPDT output contacts drop out when a fault condition or loss of power occurs
Neutral Connection RequirementDoes not require a neutral connection
System CompatibilityWye or Delta systems
Warranty5-year Unconditional Warranty

FAQs

What voltage ranges does the 20VB monitor support for operation and fault detection?
The 20VB operates within 190-480 VAC. It detects under-voltage trips from 185-480VAC and over-voltage trips from 208-528VAC.
Are the trip and restart delays adjustable on the 20VB monitor?
Yes, the trip delay for over, under, and unbalanced conditions is adjustable from 1-30 seconds. The restart delay is adjustable from 1-500 seconds.
What types of electrical faults does the 20VB monitor detect?
The 20VB monitors for phase loss, phase reversal, over-voltage, under-voltage, and voltage unbalance conditions.