1. What is G4 bulb?

G4 bulb belongs to one typical kind of bi-pin socket bulbs, with 2 straight pins as the input end. The number 4 after “G” means the distance between the 2 pins is 4mm. G4 is usually installed in and worked with appropriate lighting fixtures, like yard light, cabinet light, chandelier, ceiling light, wall light…etc.

Below is a picture of typical halogen G4 capsule.

2. What’s the input voltage of G4 halogen capsules?

Typical G4 halogen capsule has a low voltage input, 12V AC mostly.  Inside the lighting fixture there is an electromagnetic or electronic transformer to transform mains voltage to 12V AC voltage.

3. How to replace G4 halogen capsules with G4 Led bulbs?

G4 Led bulb consumes much less electricity than G4 halogen lamp does, moreover it’s eco-friendly and does not contain any toxic materials, it’s always a good choice to replace G4 halogen lamps with G4 led bulbs. While, in daily lives end users often find problem in this replacement, either lamp not working, or lamp flickering, or lamp going out shortly.  Here below are some tips for people who desire to replace G4 halogen lights with G4 led bulbs.

1. Identify the power of in-use G4 halogen lamps on existing light fixture, and decide which power of led bulb to choose. Usually 10W G4 halogen needs a 1.5W~2W Led bulb to replace.
2. Measure the max. allowable size inside the light fixture. This is to avoid fitting issue between G4 led bulb and your light fixture.
3. Check whether your G4 halogen lamp is powered by an electromagnetic transformer, or an electronic transformer.  In past years electronic transformers are more frequently used in various fixtures because of its lower cost.

• If it’s an electromagnetic transformer, what you need do is just to select a 12V AC G4 Led bulb with proper power & size.
• If it’s an electronic transformer, things are more complicated, because currently Led lamp has a bad compatibility with electronic transformer, and nobody can offer an universal G4 Led bulb, which has full compatibility with all kinds of electronic transformer, even Philips, Osram.  Therefore, you’d better take a couple of samples to test before you replace all G4 halogen lamps. Or, you can choose a 12V DC G4 Led bulb, and 12V DC transformers, to replace both G4 halogen lamp and halogen transformer. For new installation, it’s highly suggested to choose 12V DC G4 Led bulb & 12V DC transformer because its reliability.