Littelfuse 201A-AU Monitor
The Littelfuse 201A-AU is a critical 3-phase voltage monitor engineered to safeguard motors from catastrophic power line faults. This auto-ranging motor protection relay operates within a wide 190–480 V AC window at 50/60 Hz, making it a standard choice for HVACR contractors managing various system sizes. Using proprietary microcontroller-based circuitry, the unit provides continuous phase loss protection, voltage unbalance detection, and monitoring for over-voltage, under-voltage, and phase reversal. Designed for versatility, the Littelfuse 201A-AU features a dual-range voltage monitor configuration that automatically toggles between 200V and 400V scales, significantly reducing commissioning time for industrial motor controls. The 8-pin plug-in design allows for rapid replacement or installation on DIN-rail or surface mounts using an OT08PC socket. With adjustable trip delay (1–30s) and restart delay (manual to 500s), technicians can fine-tune nuisance tripping prevention parameters to match specific compressor or fan motor requirements.
Key Benefits for Technicians
- Advanced LED Diagnostics: Features five distinct color-coded patterns to instantly identify phase reversal, unbalance, or specific voltage faults, shortening troubleshooting cycles.
- Automated Voltage Sensing: The auto-sensing wide voltage range eliminates manual range selection, ensuring the relay is correctly configured for 208V, 240V, or 480V systems.
- Precise Field Adjustments: Includes dedicated knobs for voltage unbalance trip settings (2–8%) to accommodate older motors or sensitive electronic loads.
- Rugged System Integration: Compact polycarbonate enclosure is rated for extreme environments (-40° to 70°C), ideal for rooftop air conditioners and compressor lockout protection.
- Universal Application: Successfully protects conveyor motors, pump systems, and HVAC compressors regardless of horsepower or frame size.
Common Questions & Troubleshooting
- Can I use the Littelfuse 201A-AU for 600V systems? No, this model is rated for 190-480V. For 600V applications, use the 201-575-AU model.
- What socket is required for UL compliance? To maintain UL rating, this 8-pin monitor must be used with the Littelfuse OT08PC socket.
- How does the restart delay handle compressor head pressure? Adjust the restart delay to allow sufficient time (e.g., 180s) for system pressures to equalize, preventing short cycling and motor burnout.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Littelfuse 201A-AU Monitor
The Littelfuse 201A-AU is a critical 3-phase voltage monitor engineered to safeguard motors from catastrophic power line faults. This auto-ranging motor protection relay operates within a wide 190–480 V AC window at 50/60 Hz, making it a standard choice for HVACR contractors managing various system sizes. Using proprietary microcontroller-based circuitry, the unit provides continuous phase loss protection, voltage unbalance detection, and monitoring for over-voltage, under-voltage, and phase reversal. Designed for versatility, the Littelfuse 201A-AU features a dual-range voltage monitor configuration that automatically toggles between 200V and 400V scales, significantly reducing commissioning time for industrial motor controls. The 8-pin plug-in design allows for rapid replacement or installation on DIN-rail or surface mounts using an OT08PC socket. With adjustable trip delay (1–30s) and restart delay (manual to 500s), technicians can fine-tune nuisance tripping prevention parameters to match specific compressor or fan motor requirements.
Key Benefits for Technicians
- Advanced LED Diagnostics: Features five distinct color-coded patterns to instantly identify phase reversal, unbalance, or specific voltage faults, shortening troubleshooting cycles.
- Automated Voltage Sensing: The auto-sensing wide voltage range eliminates manual range selection, ensuring the relay is correctly configured for 208V, 240V, or 480V systems.
- Precise Field Adjustments: Includes dedicated knobs for voltage unbalance trip settings (2–8%) to accommodate older motors or sensitive electronic loads.
- Rugged System Integration: Compact polycarbonate enclosure is rated for extreme environments (-40° to 70°C), ideal for rooftop air conditioners and compressor lockout protection.
- Universal Application: Successfully protects conveyor motors, pump systems, and HVAC compressors regardless of horsepower or frame size.
Common Questions & Troubleshooting
- Can I use the Littelfuse 201A-AU for 600V systems? No, this model is rated for 190-480V. For 600V applications, use the 201-575-AU model.
- What socket is required for UL compliance? To maintain UL rating, this 8-pin monitor must be used with the Littelfuse OT08PC socket.
- How does the restart delay handle compressor head pressure? Adjust the restart delay to allow sufficient time (e.g., 180s) for system pressures to equalize, preventing short cycling and motor burnout.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
The Littelfuse 201A-AU is a critical 3-phase voltage monitor engineered to safeguard motors from catastrophic power line faults. This auto-ranging motor protection relay operates within a wide 190–480 V AC window at 50/60 Hz, making it a standard choice for HVACR contractors managing various system sizes. Using proprietary microcontroller-based circuitry, the unit provides continuous phase loss protection, voltage unbalance detection, and monitoring for over-voltage, under-voltage, and phase reversal. Designed for versatility, the Littelfuse 201A-AU features a dual-range voltage monitor configuration that automatically toggles between 200V and 400V scales, significantly reducing commissioning time for industrial motor controls. The 8-pin plug-in design allows for rapid replacement or installation on DIN-rail or surface mounts using an OT08PC socket. With adjustable trip delay (1–30s) and restart delay (manual to 500s), technicians can fine-tune nuisance tripping prevention parameters to match specific compressor or fan motor requirements.
Key Benefits for Technicians
- Advanced LED Diagnostics: Features five distinct color-coded patterns to instantly identify phase reversal, unbalance, or specific voltage faults, shortening troubleshooting cycles.
- Automated Voltage Sensing: The auto-sensing wide voltage range eliminates manual range selection, ensuring the relay is correctly configured for 208V, 240V, or 480V systems.
- Precise Field Adjustments: Includes dedicated knobs for voltage unbalance trip settings (2–8%) to accommodate older motors or sensitive electronic loads.
- Rugged System Integration: Compact polycarbonate enclosure is rated for extreme environments (-40° to 70°C), ideal for rooftop air conditioners and compressor lockout protection.
- Universal Application: Successfully protects conveyor motors, pump systems, and HVAC compressors regardless of horsepower or frame size.
Common Questions & Troubleshooting
- Can I use the Littelfuse 201A-AU for 600V systems? No, this model is rated for 190-480V. For 600V applications, use the 201-575-AU model.
- What socket is required for UL compliance? To maintain UL rating, this 8-pin monitor must be used with the Littelfuse OT08PC socket.
- How does the restart delay handle compressor head pressure? Adjust the restart delay to allow sufficient time (e.g., 180s) for system pressures to equalize, preventing short cycling and motor burnout.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
