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LED Light Bars

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The LED light bars contain an array of 5mm light emitting diodes mounted on a narrow LED circuit board. Our technicians can customize light bars to operate in very specific applications. The customization process begins by selecting an LED lamp to best suite the lighting application. The client will work with engineering to evaluate the application and select an appropriate LED light and circuit configuration. Finally, a technician will hand assemble the components, or program assembly equipment for high volume production runs.

LED light bars

LED Compatibility

A variety of 5mm LED lights are available for factory customized LED tubes. Refer to the LED light selection guide for a complete list of compatible optoelectronic components. You may access the manufacture's datasheets for detailed specifications such as luminous intensities and beam angles. Note that only the 5mm and 3mm LED lights are compatible. Refer to our educational article about LED optics for information about converting from datasheet values to radiometric flux in watts, photometric flux in lumens, or luminous intensity in candelas. Note that operating conditions and binning may cause actual results to vary.

LED Tube Clusters

Spacing between LED lights equals 0.9 inch. Adding one additional LED group to the array will decrease LED light spacing to 0.6 inch between clusters of two LED lights spaced at 0.3 inch from each other. Adding a third LED group to the LED tube will decrease all LED light spacing to 0.3 inch. LED clusters consist of a series-parallel configuration featuring one resistor per group of two LED lamps. This permits flexibility for efficient operation of both InGaN and AlInGaP technologies, within custom LED lighting designs. Each LED light bar contains three primary circuits, each with an isolated power bus. The three circuits share a common ground trace and terminal. This feature is advantageous for RGB color mixing applications. Each circuit features a resistor in series with two LEDs, which is most favorable for InGaN technologies (blue, white, green, yellow, and purple). LED arrays ship standard with one populated circuit, corresponding with one power bus and common ground. Adding additional LED clusters to the array will result in populating additional circuits, corresponding with the second and/or third power busses. The power busses may be "jumped" for simultaneous power supplied to two or three LED circuits.

Production Volumes

Our stock circuit boards will accept any standard 5mm LED lamp. A wide variety of characteristics makes this LED type most suitable for low volume customization. However, configurations used in high volume production normally do not utalize the 5mm LED. This is because several lamp alternatives offer a higher level of cost and energy efficiency. For example, a single half-watt surface mount light emitting diode component can offer up to twenty times more luminous output, at only twice the cost. If your project requires medium or high volumes, please remember to inquire about these alternative design options.

LED Printed Circuit Boards

An inner printed circuit board provides an electrical interface between each of the light emitting diodes and the current limiting resistors, as well as the power terminals. The LED wire leads pass through plated through-holes in the printed circuit board. The LED lights are hand soldered at a precise temperature. A convection-reflow oven aids surface mount resistor assembly. The oven bakes the components onto the printed circuit board surface at a precise temperature. Copper traces found on the top and bottom board layers electrically interconnect all optoelectronics. A solder mask electrically insulates the circuits, but solder joints remain non-insulated. LED light bars unequipped with a tube casing require insulating precautions. Solder joints should not make contact with electrically conductive materials, such as metals.

Customizing Length

The stock circuit board can operate as a complete board, or partial if cut to a specific length. A series of cut points allow this circuit board to continue to function normally after cut into increments. It is no longer necessary to limit your custom LED lighting design to a specific pre-set length. To calculate for the closest length to suite your needs, simply divide your required length by our smallest circuit board increment, then round up or down to the nearest whole number. Finally, account for end caps if your LED light bar will contain a polycarbonate tube casing.


All dimensions contain some tolerance. Printed circuit board width is 0.5 inch and thickness is 0.062 inch. Twenty-eight custom lengths are currently available. Minimum overall length is 1.8 inches. Maximum overall length is 50.4 inches. Light bars equipped with a tube casing also contain end caps, which increase the overall length by 1.182 inches. Custom lengths are available only in increments of 1.8 inches. Each increment may contain 2, 4, or 6 light emitting diodes. Any LED array beyond 21.6 inches in length will utilize a series of wire jumpers electrically and physically connecting a series of printed circuit boards from end to end.


A custom designed polycarbonate tube casing offers protection against the elements, as well as a convenient location to attach the mounting clips. After attaching the mounting clips to any hard surface, the LED light snaps securely into place. The ability to rotate the light bar three-hundred and sixty degrees within the mounting clip, allows fine-tuning to illuminate the desired area. As the LED light bar rotates within the mounting clips, the rubber grommet located within one end cap provides strain relief for the power wires.


Durability is an advantageous feature of the LED bar. When equipped with the shatter resistant polycarbonate tube casing, the unit can typically withstand significant abuse without presenting a failure. Slightly oversized end caps seal both ends of the tube casing. The caps offer a moisture resistant seal while providing some degree of protection against physical impact. To remove an end cap, simply apply a fair amount of force by pulling in an outward direction. This is only necessary in order to access the printed circuit board within the LED tube casing.

Protective Housing Dimensions

The outer dimension of the polycarbonate tube casing is 0.625 inch. The wall thickness of the polycarbonate material is 0.031 inch. The inner diameter of the polycarbonate tube casing is 0.563 inch with a referenced tolerance. End caps are 0.56 inch in length. Inner diameter is 0.625 inch and the outer diameter is 0.75 inch. The wire-side end cap contains a rubber grommet that extends 0.062 inch.


Plastic mounting clips may be used to mount LED arrays equipped with a tube casing. The clips allow the entire casing to rotate 360 degrees in any direction. This feature enables precise directional control during installation. Mounting hardware includes mounting clips, standard one-inch 4-40 machine screws, along with mating hex nuts. High strength double-sided adhesive can secure light bars not equipped with a tube casing. The pre-applied foam adhesive contains a peel-off backing for easy installation. LED light bars are slightly flexible when pressure is applied. It is important not to mount the unit in a permanently flexed position. Doing so may result in damage to the surface mount electronic components.

Mounting Clips

Mounting clips are for use with LED light bars equipped with tube casings. Overall mounting-clip height is 0.63 inch +/- 0.02 inch. Height from mounting surface to bottom of the tube casing is 0.06 inch +/- 0.02 inch. Additional information is located on the official mounting clip data sheets under part number V-1006. Mounting Hardware ships standard with all LED arrays equipped with a tube casing. Hardware includes standard 4-40 machine screws, measuring 1 inch in length. The screw head type is round / slotted. Screw thread type is coarse. Composition is carbon steel with Zinc plating. Also provided, are mating hex nuts, 0.098 inch in height. Thread size is also 4-40 and thread type is UNC. The nut contains a Zinc Chromate finish and thread direction is right hand.