J2 LED Lighting, LLC FAQ's

(Frequently Asked Question)

Question 1:

What is a constant current regulator (CCR) semiconductor driver?

Answer:

LEDs require the drive current to be limited to certain levels to optimize life and to determine the amount of light output.  A passive resistor is one way to limit the current but a better approach is to use a CCR semiconductor active device. Using a CCR:

  • Extends the LED life by active thermal sense which reduces current drive at higher temperatures.
  • Stabilizes light output with supply voltage fluctuations.
  • Maintains module light output over long string runs by compensating for voltage drop.
  • Produces even light output with variation in individual LED forward voltages.

  • Question 2:

    What is a Lumen?

    Answer:

    Lumen is the light output measurement (flux) of a visible light spectrum emitter. It is also the most common form of measurement for incandescent lamp output. Using lumen in J2 technical information allows us to:

  • Easily size LED light output against comparable incandescent systems rated in watts by using a typical efficiency factor for incandescent lamps of 10-15 Lumens per Watt.
  • Accurately represent our systems overall efficiency against incandescent systems.
  • Assist the user with comparison of overall light output from a given J2 LED component or system.

  • Question 3:

    What does the term Kelvin (K) mean when describing color?

    Answer:

    Kelvin (K), when referring to CCT (Correlated Color Temperature), is a means of describing white light as warm (reddish) or cool (bluish). A typical quartz halogen incandescent lamp has a light output of 3,200K.  J2 LED lighting systems are available with various degrees Kelvin:

  • Warm White: 2,700K to 3,200K
  • Neutral White: 4,000K to 4,400K
  • Daylight White: 5,000K to 7,000K
  • Enhanced White: 9,000K to 11,000K

  • Question 4:

    What is an IP rating?  What do the numbers mean?

    Answer:

    IP stands for Ingress Protection. An IP rating defines the amount of protection (typically against dust and water) inherent within a given device. Ratings follow international standards that are developed by the IEC (International Electrotechnical Commission). The numbers following the IP define the amount of protection against dust and water, respectively.  For example:

  •   A rating of IP63 defines the protection against dust as a “6” (No ingress of dust; complete protection against contact.) The “3” defines the protection against water (Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect.)
  • A rating of IP65 defines the protection against dust as a “6” (No ingress of dust; complete protection against contact) and the water protection as a “5” (Water projected by a nozzle with a 6.3mm internal diameter against enclosure from any direction shall have no harmful effects.)

  • Question 5:

    Please explain the life rating specification of 70% light output at 40,000 hours minimum.

    Answer:

    The 70% light output is in regards to lumen maintenance, or how well the light output holds to its initial value over time. Various factors such as excessive current drive and elevated temperature degrade the semiconductor device and phosphor in white LEDs. Using a constant current regulator (CCR) semiconductor LED driver limits these factors. Some inherent degradation will always take place over time and degradation may accelerate with elevated ambient operating environment temperatures.  The 40,000 hours minimum is the worst case amount of time under normal operating parameters in which the light output will drop 30% from its initial value. This can be expressed in some typical operation time period scenarios as follows:

  • 40,000 hours minimum with 10 hours per day operating is 10.0+ years.
  • 40,000 hours minimum with 24 hours per day operating is 4.5+ years.
  • The average of the above two scenarios is 7+ years to reach 40,000 hours.

  • Question 6:

    Do you have a product line suitable for vehicle or marine vessel lighting using a 12 volt DC system?

    Answer:

     We recommend the CBM and CBB products.  These devices have a robust clear PVC plastic resin molded body with an IP63 rating along with a constant current regulator (CCR). We recommend that the power system directly feeding any LED modules in a transportation application be additionally protected by a TVS (Transient Voltage Suppression) device with a maximum 29-34 DC voltage and a current surge rating of 200 amps or greater. An automotive use grade component should be selected.  A few features of the CBM and CBB series making them suitable for transportation applications are:

  • Protection against reverse voltage polarity.
  • Regulation of current to the LED in relation to temperature, self de-rating.
  • Elimination of fluctuating light output with voltage variations.
  • Contains internal protection against intermittent EOS (Electrical Over Stress) up to 35 volts DC.
  • Allows for a wide operating temperature range -25C° (13F°) to +60C° (140F°).
  • The clear molded PVC bodies provide excellent fire resistance.

  • Question 7:

    What material are the clear body types CBM and CBB made from?

    Answer:

    The bodies are made from molded PVC resin which is inherently fire resistant and is an excellent electrical insulator. In its most pure form PVC resin is clear.  PVC is commonly used in various industries (building, transportation, and medical) and is one of the most widely used wire insulations in electronic equipment and automotive wiring applications.

  • PVC is classified for flammability as an inherently self extinguishing plastic, not sustaining combustion after a flame is removed from it.
  • The excellent dielectric strength of PVC makes it suitable as an electrical insulator. Small gauge electronic equipment wire using PVC insulation is often rated at 300 volts or more.
  • As a clear plastic resin it can provide 96% light transmission. 
  • It is electrically and mechanically stable at high temperatures in a range from 80C° (176F°) to 105C° (221F°) depending on its formulation, physical geometry, and application.

  • Question 8:

    Are your string lights safety tested?

    Answer:

    Yes. The lighting string LED modules are tested and comply with the international standard developed by the IEC (International Electrotechnical Commission), speciifcation EN 62031:2008 (LED modules for general lighting – Safety specifications.) The modules are subjected to basic fault condition tests for overpower of 150% of the rated voltage for no less than 15 minutes. The test continues until the module reaches thermal stabilization. The resulting temperature rise is monitored and the test shall produce no smoke or fire, and no ignition of flammable material (tissue paper) under the module during testing. J2 products in compliance with this standard are the CBM, CBB, SBM, and TPM series.

    Question 9:

    How does a white LED work?


    Answer:

    An LED is a P-N junction semiconductor device electrically similar to a conventional diode but specifically designed to emit light, hence the name light emitting diode or LED for short. The fabrication of the semiconductor die can be done so as to achieve various light color outputs, such as blue, green, amber, red, (but not white) directly from the semiconductor. White is achieved by using a frequency converting phosphor coating over a short wavelength blue LED. The phosphor acts to lengthen the frequency of the monochromatic blue light into a broader spectrum light stretching across a wide range of the photopic (visible light 380nm to 780nm) spectrum. This frequency conversion, called a Stokes shift, moves a shorter wavelength to a longer wavelength.  Blue LEDs emit light in shorter wavelengths.  A typical blue LED may have an output somewhere from 425nm to 475nm and the phosphor conversion of the wavelength will produce a strong broad band light output in the 500nm to 700nm range. A few key aspects of white LEDs are:

  • High efficiency: white LED technology has now achieved over 100 lumens per watt.
  • Ability to manufacture with different white light color temperatures.
  • High reliability of Solid State Lighting (SSL).
  • Small size.
  • Low voltage.

  • Question 10:

    Do LEDs perform poorly at low temperatures like fluorescent lamps do?

    Answer:

    No. Fluorescent lamps contain mercury which condenses to the coldest point of the lamp, which at low temperatures tends to be the lamp wall. This starves the lamp of mercury vapor that forms the plasma discharge used to generate ultraviolet light which stimulates the phosphor coating of the lamps’ walls to produce light. The result of this is poor light output at low temperatures. LEDs contain no mercury and are semiconductor devices, with a temperature response curve opposite of fluorescent lamps. Output rises at low temperatures and drops at higher temperatures. A few temperature related characteristics of LEDs include:

  • Characterization on specification sheets for light output is at 25C° (77F°).
  • Operation at higher temperature 75C° (167F°) can provide a nominal light output decrease of -5% for the J2 CBM, CBB, SBM, and TPM series.

  • Question 11:

    Are there any chemicals to avoid exposing white LEDs to?

    Answer:

    Yes. Many chemicals will degrade the phosphor of the LED. The vapors of many solvents can permeate the clear protective covering of the LED and migrate to the phosphor. A few common solvents to avoid and their typical uses are listed below. If you use these solvents or products containing these solvents in assembly, be sure that any residual vapors are dissipated before installing the LED modules. If you are cleaning mounting surfaces for the LED modules adhesive tape use IPA (isopropyl alcohol). Solvents to avoid include:

  • MEK (Methyl Ethly Keytone): used in PVC solvent cement and in spray paints.
  • Toluene: used in spray paints, and plastics cement.
  • Xylene: used in spray paints and as epoxy thinner.
  • MIBK (Methyl Isobutyl Ketone): used in adhesives, to thin resins, and as a cleaning solvent.

  • Question 12:

    What wire type and size do you recommend using with SSL (Solid State Lighting) LED systems and power supplies?

    Answer:

    The UL1015 type is suitable for most commercial electronic applications for wiring inside enclosures and is rated to 105C° (221F°). Wire of similar characteristics is also available as MIL-W-16878-1.  These grades of wire have a thick PVC insulation with a typical wall thickness of 0.03” and   0.01” that resists abrasion. For use in transportation the equivalent PVC wire is type GPT that meets SAE specification J-1128. It is similar to the commercial wire but rated to 80C° (176F°) and restricted to low voltage use. 

    Suitable wire gauges are given below for most low voltage SSL applications. Also given are the typical amperage ratings for the wire size along with the wattage calculation for 12 volt systems. For general design practices it is advisable to de-rate the overall wattage anticipated by 15%-20%. In relation to this practice the various matched power supply wattages for de-rated wire are given. This design practice provides margin for overpower and temperature conditions.    

  • 20 Awg, 7.50 amps at 12.0 volts (90 watts), de-rated to 75 watt power supply.  
  • 18 Awg, 10.0 amps at 12.0 volts (120 watts), de-rated to 100 watt power supply.
  • 16 Awg, 13.0 amps at 12.0 volts (156 watts), de-rated to 130 watt power supply.
  • 14 Awg, 17.0 amps at 12.0 volts (238 watts), de-rated to 200 watt power supply.

  • Question 13:

    I want to operate the PIR1 motion detector switch on a 12 volt DC sealed lead acid battery system. Will it operate in the expected voltage range of 10 to 15 volts DC? And what will be the idle current of the PIR1 motion detector?

    Answer:

    The PIR1 motion detector will operate in the 10 – 15 volt DC range that would be expected in the normal charge and discharge cycles of a sealed lead acid battery. The idle current is 2.25mA typical and for worst case calculations 4.0mA maximum.


    Question 14:

    I want to operate the ALS1 Ambient Light Switch sunlight detecting dusk to dawn control on a 12 volt DC sealed lead acid battery system. Will it operate in the expected voltage range of 10 to 15 volts DC? And what will be the idle current of the ALS1 Ambient Light Switch be?

    Answer:

    The ALS1 Ambient Light Switch will operate in the 10 – 15 volt DC range that would be expected in the normal charge and discharge cycles of a sealed lead acid battery. The idle current is 2.25mA typical and for worst case calculations 4.0mA maximum.


    Question 15:

    Is the ALS1 Ambient Light Switch sunlight detecting dusk to dawn control water proof for use in outdoor environments?

    Answer:

    The ALS1 Ambient Light Switch is minimally “weather resistant” and needs to be mounted so as to protect from direct exposure to water / moisture. For outdoor mounting a sheet metal rain shield can be utilized. To seal the connector terminal block area for resistance to moisture, RTV (Room Temperature Volcanizing) silicone is recommended. A non-corrosive type (no acetic acid), must be used to seal the area of the terminal block enclosure. For the DIY user GE Silicone II (GE500) from big box home improvement stores can be used. For OEM commercial / industrial user the Dow Corning 3145 is recommended.

    For marine, dock side, or other heavy water and moisture exposure environments, the ALS can be mounted in an appropriate NEMA or IP rated enclosure with a clear polycarbonate sealing cover.


    Question 16:

    What level of moisture protection do the SCLED-12V1A and SCLED-12V3A 12 volt DC solar panel controllers with dusk to dawn function have?

    Answer:

    The controller enclosures are “weather resistant” not “water proof”. To ensure an extended life of your controller, mount it in a semi-covered place out of the elements. To improve resistance to moisture, RTV (Room Temperature Volcanizing) silicone is recommended of the non-corrosive type (no acetic acid), to seal the enclosure. For the DIY user GE Silicone II (GE500) from big box home improvement stores can be used. For OEM commercial / industrial user the Dow Corning 3145 is recommended.