Generac 9955 150 Amp Automatic Transfer Switch Nema 3R

Product Description

The GENERAC 9955 is a 150-amp, single-phase, service-rated automatic transfer switch designed to shift electrical load from a utility power source to a standby generator source when utility power fails or drops to an unacceptable level. Rated NEMA 3R for outdoor and covered indoor use, it includes a utility service disconnect circuit breaker and a fused control module with brownout protection. Transfer occurs automatically once the generator output reaches an acceptable voltage and frequency. Licensed electricians install this unit as part of a compliant standby power system in residential and light commercial applications.

This transfer switch is suited for single-phase standby power installations where a service-rated disconnect is required at or near the utility entry point. The NEMA 3R enclosure rating makes it appropriate for installations exposed to rain, sleet, and exterior conditions. The integrated utility service disconnect eliminates the need for a separate disconnect at the service entrance, streamlining the installation. The fused control module with brownout protection helps guard against damage caused by low-voltage utility conditions before a full outage triggers the transfer sequence.

Key Features

• 150-amp service-rated automatic transfer for utility-to-generator load switching
• Single-phase configuration for residential and light commercial standby systems
• NEMA 3R enclosure rated for outdoor installation
• Integrated utility service disconnect circuit breaker
• Fused control module with brownout protection
• Prevents electrical feedback between utility and generator sources as required by code

Compatibility

Designed as a service-rated automatic transfer switch for use with single-phase standby generator systems requiring a 150-amp utility disconnect and automatic load transfer capability.

Installation Notes

Installation must be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and all applicable local codes. Utility power and generator output must both be confirmed de-energized before making any wiring connections. The utility service disconnect built into this unit should be placed in the OFF position before beginning work. Do not connect utility and generator sources simultaneously outside of the transfer switch mechanism.

Technical Specifications

• Amperage: 150 amps
• Phase: Single-phase
• Enclosure Rating: NEMA 3R
• Transfer Type: Automatic
• Length: 13.5 inches
• Width: 6.5 inches
• Height: 30 inches
• Weight: 39 pounds

Standard Information

• Brand: GENERAC
• Manufacturer Part Number: 9955