How Fluorescent Lamp (Tube Light) works on DC Supply?

How Tube Light (Fluorescent Lamp) works on DC Supply?

The Fluorescent lamps which is commonly known as Tube light can be operated on DC supply.  

In this post, let us discuss about how to make tube light works on DC supply. 

To make the fluorescent lamp work on DC Supply, a resistance is connected in addition to the usual choke as shown in the following figure.
tubelight_on DC_Supply

  • After adding the extra resistance and connected to DC supply continuously, the positive end of the tube will become blackened.
  • It is due to the migration of ionized mercury vapour to the negative end.
  • To decrease this effect, the input supply terminals have to be changed continuously.
  • To achieve this, a changeover switch is used. Usually a rotary switch is incorporated. It ensures the polarity reversal, every time the fluorescent lamp is switched ON.

The advantages and disadvantages of working tube light on DC supply is given below:


  1. It eliminates the stroboscopic effect.
  2. Power factor correction is not required.


  1. Initial Investment cost is high.
  2. Due to the addition of the extra resistor, power consumption is increased.
  3. Tube light efficiency is decreased.

You May also like to Read:

How to use Bridge Rectifier IC? How to identify Terminals?
How to test LED using Multimeter? How to identify LED terminals?
How to Identify NPN and PNP Transistor using Multimeter

Thanks for reading... Please leave your comments below.... Please subscribe to get new posts to your mail ID..

You may also like...

1 Response

  1. shashidhar says:

    Dear Admin,
    A tube light fed with DC.... whether the starter is useful ?.. and will the choke develop high voltage?

Leave a Reply

Your email address will not be published. Required fields are marked *