The LH1165 A.A.G. Stucchi 3249-9S-U-PBT-R is a G13 medium-based, push-fit, snap-in or slide-on, mounting, non-shunted* lamp holder with nib. The T8/T10/T12 (G13 base) tombstone style fluorescent or LED lamp holder has a turn and lock insertion to keep the LED or fluorescent tubular lamps in a fixed position. The A.A.G. Stucchi 3249-9S-U-PBT-R is a low-profile tombstone with a lamp axis of 23mm. The lamp axis is height at which the center of the lamp meets the lamp holder. It is rated up to 660W-600V, is cULus and RoHS certified and has a post, stop or nib for mounting into the fixture. The locator post also known as the post, stop or nib positions the socket on the fixture. The A.A.G. Stucchi 3249-9S-U-PBT-R has bottom quick connects that allows for easy installation of wiring. Used with rapid start and program start ballasts and LED bulbs that require a non-shunted* lamp holder. It is made of durable polycarbonate and has a red rotor.
*The primary difference between shunted and non-shunted lamp holders (also known as tombstones or sockets) lies in how the electrical current flows through them to the lamp pins:
Shunted Lamp Holders:
- Internal Connection: Shunted lamp holders have their two electrical contacts internally connected or "shunted." This means there's a single electrical path through the socket.
- Single Wiring Track: They receive voltage through a single set of wires that then spreads to both contacts that connect with the lamp pins.
- Continuity: If you test a shunted socket for continuity across its two contacts, a multimeter will show a closed circuit (it will beep or light up).
- Usage: Shunted lamp holders are typically used with:
o Instant start ballasts in fluorescent lighting. These ballasts provide a high initial voltage to start the lamp and require the pins at each end to be at the same electrical potential initially.
o Some plug-and-play LED tubes that are designed to work with existing instant start ballasts.
o Double-ended direct wire LED tubes: Although they can also work with non-shunted sockets, shunted sockets are an option.
Non-Shunted Lamp Holders:
- Separate Contacts: Non-shunted lamp holders have two separate electrical contacts that are not internally connected. This creates two distinct electrical paths.
- Dual Wiring Tracks: They require two separate wires (line and neutral) to connect to the two contacts within the socket. Each contact receives voltage independently.
- No Continuity: Testing a non-shunted socket for continuity across its two contacts will show an open circuit (no beep or light up on the multimeter).
- Usage: Non-shunted lamp holders are required for:
o Rapid start, programmed start, and dimming ballasts in fluorescent lighting. These ballasts preheat the lamp filaments, and each end of the lamp needs to be connected separately to the ballast.
o Single-ended direct wire (ballast bypass) LED tubes: These tubes receive power on one end only, requiring separate line and neutral connections to the non-shunted socket on that end. The sockets on the other end simply provide mechanical support.
o Some plug-and-play LED tubes designed to work with specific ballast types (like rapid or programmed start).