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Lamp Removal Tool
LRT Lamp Removal Tool
388LP-X Replaces T-1ĺ Sub-Miniature Lamps Incandescent Lamp #388
388LP-X 388LP-X Replaces T-1ĺ Sub-Miniature Lamps Incandescent Lamp #388
MB400-X120-4AL1 LED Annunciator Retrofit Lamps SMT Cluster
MB400-X120-4AL1 MB400-X120-4AL1 LED Annunciator Retrofit Lamps SMT Cluster
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FAQ

  Q. How does polarity affect an LED?
  Q. Can I use a white LED behind any colored lens?
  Q. What does the shunt resistor do?
  Q. Why are some green, blue, and white LEDs more expensive than red and amber?
  Q. What is the difference between DDP's Power-Line LED lamps and standard LED lamps offered from ddpleds.com?
  Q. What if I canít find the incandescent lamp number in your cross reference list?
  Q. Why are LED lamps more expensive than incandescent bulbs?
  Q. Is there a warranty?

Q. How does polarity affect an LED?
A. Most DDP Power-Line LED lamps are designed with an integrated bi-polar bridge. Thereby, the LED will illuminate regardless of polarity or socket wiring. Normally, LEDs are polarity sensitive, i.e., they will not illuminate when plugged in the wrong polarity. While this doesnít harm the LED, it may cause the installer to believe the LED lamp is defective when it doesnít illuminate.
Q. Can I use a white LED behind any colored lens?
A. Yes, but the effect may be undesirable. White LEDs will not produce a true lens color as well as a colored LED. However, many users prefer to purchase a single LED lamp for all of their applications. It is best to try both and decide which you prefer.
Q. What does the shunt resistor do?
A. A shunt resistor is an internal parallel resistor that simply shields the LED from noise. Sometimes, an LED will glow with as little as 2mA current in the circuit. This is usually caused by transient voltage from a relay or discharge from a capacitor. Also, inherent in the design of some programmable logic controllers (PLCs) is a triac protective circuit that may supply up to 5mA of leakage current in the OFF state.
Q. Why are some green, blue, and white LEDs more expensive than red and amber?
A. The green, blue, and white LED lamps incorporate a relatively new technology called Gallium Nitride (GaN). While prices are presently lower than when this technology was introduced a few years ago, it is still more expensive than the red and amber chips that have been around for many years.
Q. What is the difference between DDP's Power-Line LED lamps and standard LED lamps offered from ddpleds.com?
A. The DDP Power-Line lamps represent the most commonly used bulbs used in utilities and industrial facilities. Designed for demanding operating environments, most DDP Power-Line LEDs incorporate a full-wave bridge rectifier for bi-polar operation and an optional shunt resistor to eliminate false "on" indication. And, DDP Power-Line LEDs offer easily recognizable part numbers with drop-in installation into existing sockets and panels.
Q. What if I canít find the incandescent lamp number in your cross reference list?
A. With over 30-yearsí experience designing LED lamps, we have encountered thousands of applications and will likely have a solution to suit your needs. Simply call or e-mail us with your incandescent lamp number, or description of your application, and we can quickly provide you with a part number and a sample.
Q. Why are LED lamps more expensive than incandescent bulbs?
A. DDP Power-Line LED lamps are sophisticated solid-state devices. Incandescent filament bulbs do not have complex electronic circuitry and are extremely unreliable. While the unit price may be higher for the LED lamp, the user will usually realize a payback of less than one year due to the long life of the LED.
Q. Is there a warranty?
A. All of our products are warranted against defects of manufacture for 3 years from date of purchase, providing they have been subjected to normal use and service. Any replacement will be made at no charge except for necessary shipping charges. Returns shall be effected as follows: (1) call factory for return authorization number, and (2) return products with authorization number prominently displayed, postage prepaid, to Data Display Products at the address listed. This warranty is expressly in lieu of all other warranties expressed or implied and does not extend in any way to consequential or incidental damages, including injury to persons or damage to property. The terms of this warranty may not be amended, altered or extended except by an instrument in writing executed by an officer of Data Display Products.