Reliance Controls Pro/Tran 2 306A review: a 6-circuit transfer switch for safe generator backup

This is a research-based review, based on manufacturer specs and published data. We do not test products. Specs come from Reliance Controls' page for the Pro/Tran 2 306A, checked November 1, 2026. This page is information only: a transfer switch is installed by a licensed electrician, and nothing here is installation advice.

Running appliances on extension cords works for a fridge and a lamp. It does not work for hardwired loads: a furnace blower, a well pump, a sump pump on its own circuit or ceiling lights. Those need power delivered through the house wiring, and the only safe way to do that from a portable generator is a transfer switch or a panel interlock.

Reliance Controls makes the Pro/Tran line of manual switches. The 306A mounts beside the main panel and takes over six chosen circuits. During an outage, the generator plugs into an outdoor inlet, and you flip each chosen circuit from utility power to generator power. Reliance says the design eliminates dangerous back-feeding and protects utility workers.

Who should buy it

• Owners of a 240 V portable generator with an L14-30R outlet, such as the Westinghouse WGen9500DFc, who want to run hardwired essentials.
• Homes on a well: the 2-pole 20 A circuit can carry a 240 V load such as a well pump, if the electrician confirms the pump fits.
• Owners of a 120/240 V battery system, such as the EcoFlow DELTA Pro 3, since Reliance says the switch works with battery power stations too.

Who should skip it

• Renters and anyone who cannot have permanent wiring changes made.
• Owners of 120 V-only generators such as the Honda EU2200i. An L14-30 inlet expects a 120/240 V source; ask an electrician about a 120 V setup.
• Homes that want the whole panel backed up. Six circuits at 30 A covers essentials; whole-home backup needs a larger switch or interlock sized by an electrician.

Strengths

• No back-feeding. Each circuit is either on utility power or on the generator, never both, which Reliance says protects utility workers.
• Wattmeters. Built-in meters show how much each side of the generator is carrying, so you can balance the load.
• A 240 V circuit. One 2-pole 20 A breaker for a 240 V load.
• Flexible. Reliance says it accepts any UL-listed 1 in. interchangeable breaker and can be reconfigured in the field for more double-pole circuits.
• Listed. Reliance states cULus 1008 listing.
• Battery-ready. Reliance says it works with portable generators, battery power stations and hybrid setups.

Drawbacks

• Professional install. Wiring to the panel, an outdoor inlet and a permit and inspection where required. Budget for the electrician's time as well as the switch.
• Six circuits. You choose what gets backed up; everything else stays dark.
• 30 A limit. About 7,200 watts at 240 V (our arithmetic), even if the generator makes more.
• Manual. Someone has to be home to flip the switches when the power fails and again when it returns.
• Indoor cabinet. The 306A is an indoor enclosure; it mounts inside near the panel.

How it compares

The alternatives are a smaller Reliance switch and the cord-only approach. Specs are from each manufacturer's page, checked November 1, 2026.

Using it in a long outage

Who installs it, and why

Mecklenburg County, North Carolina's code enforcement office says you must have a qualified electrician install a manual or automatic transfer switch, that the switch should be certified by UL, CSA or another independent test lab and mounted in an electrical box, and that permits and inspections are required to connect a generator to a building's permanent wiring. Rules vary by jurisdiction, so ask your electrician or building department. The installer also checks generator grounding: some generators have a bonded neutral (Westinghouse lists one for the WGen9500DFc), and Reliance publishes guidance on bonded versus floating neutral.

Choosing six circuits

• Refrigerator and a freezer.
• Furnace or boiler controls and blower, so gas heat can run in winter.
• Well pump (on the 2-pole circuit) or a sump pump.
• One lighting circuit and one outlet circuit for phones, router and medical devices.
• Leave out the water heater, range, dryer and central air unless the electrician confirms the load fits within 30 A and the generator's running watts.

Switching over during an outage

1. 01Start the generator outdoors, more than 20 feet from windows, doors and vents (CDC), with CO alarms working inside.
2. 02Connect the generator to the outdoor inlet with a 30 A cord, then move circuits to generator power one at a time, starting with the largest motor load.
3. 03Watch the wattmeters and keep both sides balanced and under the generator's rating.
4. 04When grid power returns, switch circuits back to utility power following Reliance's operating instructions.
5. 05Let the generator cool before refueling. Ready.gov warns fuel spilled on hot engine parts can ignite.