Convert your 4-ft shop fluorescent fixtures to LED bulbs easily. There are basically three types of LED bulbs made to convert fluorescent lights to LED.
The simplest, but not the best, is a ‘ballast’ driven LED bulb. To convert this fixture to LED read the ballast inside the fixture and see if it is magnetic or electronic. Order the LED to match the ballast and simply install the correct bulb and away you go.
It’s not the best type of install because the ballast is wasting electricity. Not only that but the ballast has a life cycle and some day it will fail and need to be replaced. Why not use a direct ‘line voltage’ LED bulb that is fed house current without the ballast?
Then other two require some simple rewiring.
The two ‘line voltage’ LED bulbs are a little confusing as to how the power gets to the bulb.
One type is fed electricity on opposite ends of the bulb, black wire on one end, white on the other.
A tombstone with separate contacts can be used on a non-shunted bulb because you can still put the black wire to one end of the fixture and the white to the other. This makes it a shunted fixture.
The other type is fed black and white to one end only. The opposite end of the ‘one end feed’ bulb is not powered; the prongs are only to hold the bulb in the fixture. Some tombstones are ‘shunted’ meaning both contacts in that tombstone are connected together and not separable.
The other type of tombstone has separate contacts so power can be put to one end only.
Fluorescent and LED’s rotate into raised sockets on either end of the fixture, called tombstones.
Depending on the existing wiring of the fixture:
A shunted fixture will have to get shunted bulbs or replace the tombstones to non-shunted for end feed bulbs. Both situations are very acceptable so the fixture and availability of the bulbs will determine which bulb you want to purchase.
Hopefully this information and some help from the retailer of the bulbs will provide you with an easy conversion which will save you dollars in electricity for years to come.