SATCO Lighting S16503 LED Circline, 16W, T9, 3000K, G10Q Base, 120-277V, Type B, Ballast Bypass

No. The S16503 is a Type B ballast bypass lamp, which means the existing fluorescent ballast has to be removed and line voltage wired directly to the G10q socket. Drop it into a circline fixture with the ballast still in place and it won't work. Once bypassed it runs on anything from 120 to 277 volts at 50/60Hz, so the same lamp covers residential 120V and commercial 277V lighting circuits.

Yes, the base is G10q 4-pin, the same base used on T9 fluorescent circlines, and the lamp is a T9 shape. Mechanically it drops into the existing socket. Electrically it does not, because the ballast has to come out first.

No. This 16W circline is not dimmable, and it has no three-way function either. Wire it to a plain switched circuit. Leaving it on an existing dimmer risks flicker and early failure, so if the fixture is dimmer-fed, the control needs to be swapped for a standard switch.

Enclosed rated, so it can be installed in a sealed drum or pan fixture where the heat has nowhere to go, which is where a lot of LED lamps fail early. It is rated for damp locations, so a bathroom ceiling or a covered porch is fine. Wet locations, meaning direct water exposure, are not covered. It also mounts in any orientation, base up, base down, or horizontal.

1600 lumens from 16 watts, which Satco rates as a 100W incandescent equivalent. Color is 3000K warm white with 80 CRI, and the beam spreads 135 degrees behind a frosted lens, so it washes a ceiling fixture rather than throwing a spot.

Yes, the S16503 is Title 24 compliant, which matters if you're spec'ing lamps for California work. It is also FCC compliant for electromagnetic interference. Note that it is not DLC listed, so it won't qualify for utility rebate programs that require a DLC listing.

Rated at 50,000 hours. In a common-area fixture running 12 hours a day that's over eleven years of service, which is why property managers move circline fixtures to ballast bypass LED rather than keep buying fluorescent tubes and replacement ballasts. The housing is white and the lens is frosted, so the look stays consistent across a fleet of fixtures.

The S16503 is fixed at 3000K warm white, with no CCT selector switch on the lamp. If you need 3500K or 4000K in the same fixture, that's a different Satco part number, not an option on this one. Match the 3000K to whatever is already in adjacent fixtures or the difference will be obvious across a lobby ceiling.

Each lamp draws 0.133A at 120V down to 0.058A at 277V, at 16 watts. On a 120V branch circuit that's roughly seven and a half lamps per amp, so a 15A circuit carries far more circline fixtures on LED than it did on fluorescent ballasts.