Lamp Holders for Florescent Tubes and LED retrofits

There are 4 basic types of florescent tube lamp holders: G5, G13, FA8 and R17D. Bulbs are shown at the right. G5 and G13 are similar with 2 pins on each end. Note: If you break a holder, it can easily be replaced. 



G13 bipin is the most common holder, used for 4′ T8 and T12 tubes with 2 pins on each end. To insert a tube, you line up the pins with the middle slot, insert and twist 90 degrees. In typical home and older fixtures each pin in the holder is electrically separated called non-shunted. Commercial fixtures typically use shunted (shorted) connectors. More about shunted holders… Purchase non-shunted holders…




T5 bulbs are 5/8″ in diameter and require a smaller G5 bipin holder that is similar to the G13. Shoplight will special order t5 LED replacement tubes, ask for a quote




FA8 is a single large pin holder used for 8′ tubes. You insert the tube by pushing against the spring loaded end. Shoplight offers 8′ tubes with FA8 ends.




R17D is for high output tubes. Like the FA8, it is spring loaded. Shoplight offers 8′ tubes with R17D ends.


Recycling – Florescent Disposal

You are obligated to recycle florescent tubes because they contain mercury. The old ballast should be recycled as well. If they do not say “Non-PCB”, then they contain toxic PCB and will cost more to recycle. Often people leave the old ballast in the fixture to avoid this cost.

Your local waste management company may have an associated company that will handle recycling of the tubes. Generally this involves boxing the tubes in groups of 25 to 40. Prices are based on length of tube, cost of boxes and handling fees. You can expect to pay $1-2 per tube. The best deal in the Columbus area is Batteries + Bulbs. We will be adding more to our recycling document from time-to time.

Shunted G13 Lamp Holders Tombstones

Many commercial florescent fixtures use shunted lamp holders (tombstones). That means the pins will be shorted together. These will not work with by-pass tubes. You want non-shunted G13 holders

Generally a shunted lamp holder will have only one wire connected to it. Once you take off the fixture’s reflector, check to see if there is one or 2 wires for each side of each holder. Using an ohm meter or continuity tester, make sure each side is independent and not jumpered together. Sometimes you can modify the tombstones and other times it is easier to replace them. Shoplight Solutions stocks new G13 lamp holders.

Below is an example of a shunted tombstone that cannot be repaired.

Below is a repairable holder with a removable shunt.

Here is the repaired tombstone. Note a new hole was carefully drilled in the bottom for the second wire.

Color Rendering Index (CRI)

Numerically, the highest possible CRI value is 100, and would only be given to a source identical to standardized daylight. Low-pressure sodium lighting has negative CRI; fluorescent lights range from about 50 for the basic types. Typical LEDs have about 75+ CRI. As you can see in the graphs below, a florescent bulb has large gaps in its spectrum which accounts for the poor CRI and contributes to eye strain.


Shoplight Solutions now offers LED strip with CRI > 94. So if you are displaying artwork, photography, neo-natal, flowers, food or inspecting products, CRI should be especially important to you and these strips can help provide the answer.

Ingress Protection (IP) Rating

The IP system is an internationally recognized method to indicate the degree of protection against the ingress of dust, solid objects and moisture into an enclosure. The letters “IP” are followed by two numerals.

First Numeral – Objects and Dust

0 Not protected
1 Protected against solid objects 50 mm in diameter or greater.
A large surface of the body, such as a hand (no protection against deliberate access).
2 Protected against solid objects 12 mm in diameter or greater.
Fingers or similar objects not exceeding 80mm in length.
3 Protected against solid objects 2.5 mm in diameter or greater.
Tools, wires, etc., of diameter or thickness greater than 2.5 mm.
4 Protected against solid objects 1mm in diameter or greater.
Wires or other similar solid material of thickness greater than 1mm in diameter.
5 Dust protected.
Dust does not enter in sufficient quantity to interfere with satisfactory operation of equipment.
6 Dust tight.
No ingress of dust.

Second Numeral – Water and Moisture

0 Not protected
1 Protected against dripping water.
Dripping water (vertically falling drops) shall have no harmful effect.
2 Protected against dripping water when tilted up to 15°.
Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle up to 15º from its normal position.
3 Protected against spraying water.
Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect.
4 Protected against splashing water.
Water splashing against the enclosure from any direction shall have no harmful effect.
5 Protected against water jets.
Water projected by a nozzle against enclosure from any direction shall have no harmful effects.
6 Protected against heavy seas.
Water from heavy seas or projected in powerful water jets shall not enter the enclosure in harmful quantities.
7 Protected against the effects of temporary immersion.
Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under
defined conditions of pressure and time.
8 Protected against continuous immersion.
The equipment is suitable for continuous submersion in water under conditions which shall be specified
by the manufacturer.

Impact Rating (IK)

Degrees of protection provided by enclosures for electrical equipment against external mechanical impacts in accordance with IEC 62262:2002 and IEC 60068-2-75:1997.

00 Not protected
01 Protected against 0.14 joules impact.
Equivalent to impact of 0.25kg mass dropped from 56mm above impacted surface.
02 Protected against 0.2 joules impact.
Equivalent to impact of 0.25kg mass dropped from 80 mm above impacted surface.
03 Protected against 0.35 joules impact.
Equivalent to impact of 0.25kg mass dropped from 140 mm above impacted surface.
04 Protected against 0.5 joules impact.
Equivalent to impact of 0.25kg mass dropped from 200 mm above impacted surface.
05 Protected against 0.7 joules impact.
Equivalent to impact of 0.25kg mass dropped from 280 mm above impacted surface.
06 Protected against 1 joules impact.
Equivalent to impact of 0.25kg mass dropped from 400 mm above impacted surface.
07 Protected against 2 joules impact.
Equivalent to impact of 0.5kg mass dropped from 400 mm above impacted surface.
08 Protected against 5 joules impact.
Equivalent to impact of 1.7kg mass dropped from 300 mm above impacted surface.
09 Protected against 10 joules impact.
Equivalent to impact of 5kg mass dropped from 200 mm above impacted surface.
10 Protected against 20 joules impact.
Equivalent to impact of 5kg mass dropped from 400 mm above impacted surface.

Color Temperature CCT

Correlated Color Temperature measured in degrees Kelvin is the industryled-color-temperature way of describing a light’s color. As you heat a piece of iron, it glows red, then white as it gets hotter. An incandescent blub produces light with a glowing filament at about 2700K. This is called warm light, the kind we are accustomed to in our homes. We actually see better for tasks with a brighter white, almost bluish, like being outside on a bright day. Shoplight Solutions offers LED strip in both warm (2700K) and bright white (6500K). Our fixtures are typically 5000K but can be specified with different CCTs.

For more information visit: Wikipedia