3-Phase Monitor with Adjustable Trip & Restart Delays
The MODEL 20AA-M 3-Phase Monitor provides essential protection for industrial systems. This unit monitors critical conditions including phase loss, phase reversal, over/under voltage, and voltage unbalance across a broad 190-480 VAC operating range. Its adjustable trip delay, configurable from 1 to 30 seconds, allows for precise response to transient faults, preventing unnecessary shutdowns. Furthermore, the adjustable restart delay, ranging from 1 to 500 seconds, facilitates controlled system re-engagement after a fault condition has cleared. The manual reset functionality, requiring an external momentary pushbutton, ensures operator intervention for safety and system integrity. With dual 7.5A at 240VAC resistive output contacts and a durable Noryl plastic enclosure, the 20AA-M offers reliable performance and integration flexibility. This monitor is designed for critical applications demanding consistent power quality oversight and robust equipment protection.
Unv 3Ph Monitor
Specifications
| Model Type | Manual Reset |
|---|---|
| Manual Reset Requirement | External N.O. momentary pushbutton required for manual reset. |
| Monitored Conditions | Phase Loss, Phase Reversal, Over/Under Voltage and Voltage Unbalance |
| Indicators | LED Status Indicators |
| Operating Voltage | 190-480 VAC |
| Power Consumption | 3.7W at 480V |
| Auto Ranges | Yes |
| Frequency | 50/60Hz |
| Type of Measurement | RMS |
| Under Voltage Trip | 90% ±1% (% of setpoint) |
| Under Voltage Reset | 93% ±1% (% of setpoint) |
| Over Voltage Trip | 110% ±1% (% of setpoint) |
| Over Voltage Reset | 107% ±1% (% of setpoint) |
| Voltage Unbalance Trip | 2-8%, adjustable |
| Voltage Unbalance Conformance | NEMA |
| Voltage Unbalance Reset | Trip setting minus 0.7% |
| Trip Delay Time (Over, Under, & Unbalanced) | 1-30 sec., adjustable |
| Trip Delay Time (Single-Phasing Faults) | 1 sec., fixed |
| Trip Delay Time (Unbalance > 15%) | 1 sec., fixed |
| Restart Delay | 1-500 sec., adjustable |
| Manual Reset Input | 5V open circuit/500µA short circuit |
| Output Contacts | 2x N.O. (Isolated) |
| Output Contact Rating | 7.5A at 240VAC resistive |
| 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 |
| Dimension Tolerance | ±0.06 |
| Optional Feature | /SG = Silver with Gold Flash Contacts |
| Warranty | 5-year Unconditional Warranty |
