3-Phase Voltage Band Monitor with Adjustable Trip & Restart Delays
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.
3Ph/Adj/Hv/Lv/Td/Rd
Specifications
| Operating Voltage | 190-480 VAC |
|---|---|
| Frequency | 50/60Hz |
| Type of Measurement | RMS |
| Auto Ranges | Yes |
| Under Voltage Trip Range | 185-480VAC |
| Under Voltage Reset | Trip setting +3% |
| Over Voltage Trip Range | 208-528VAC |
| Over Voltage Reset | Trip setting -3% |
| Voltage Unbalance Trip | 6%, Fixed |
| Voltage Unbalance Reset | 5% 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 Delay | 1-500 sec., adjustable |
| Restart Delay Reset Type | Automatic |
| Output Contacts | SPDT 10A at 240VAC resistive |
| Power Consumption | 3W |
| Operating Temperature | -20° to +140° F |
| Humidity Tolerance | 0-97% w/o condensation |
| Terminal Torque | 3.5 in. lbs. maximum |
| Wire Type | Stranded or solid 14-26 AWG, 1/terminal |
| Enclosure Material | NORYL plastic |
| Mounting | DIN Rail or Surface Mount |
| Additional Options | /SG = Silver with Gold Flash Contacts |
| Agency Approval | UL Recognized (U.S. and Canada) (For use in a Pollution Degree 2 Environment) |
| Monitored Conditions | Phase Loss, Phase Reversal, Over/Under Voltage and Voltage Unbalance |
| Relay Operation | Fail-safe, i.e. the SPDT output contacts drop out when a fault condition or loss of power occurs |
| Neutral Connection Requirement | Does not require a neutral connection |
| System Compatibility | Wye or Delta systems |
| Warranty | 5-year Unconditional Warranty |





