Test Your Ballast

Don’t just take our word for it, do the test yourself!

Our message to growers and retailers is simple: When it comes to knowing which ballasts perform to European standards don’t just take our word for it, test a ballast yourself! Performing your own ballast test at home couldn’t be easier. At minimum all you need is an energy meter and our test method to see if your ballast is drawing enough energy to power a 600W lamp correctly. Next, watch our video guide below and you’re ready. If you have a light meter you can use this to get a good indication of the comparative light difference as well.

If you want to know more on ballast testing, see how an indoor gardening store conducts ballast testing in store for customers here.

How to test your ballast output

You can test ballast power output for yourself! Follow this guide to see how your 600W magnetic ballast measures up.

Using an energy meter, available from online electrical stores for between £15.00 and £35.00, you can test the performance of a ballast by following these steps:

Before testing

  • Make sure you use the same type of lamp for each test.
  • Run in the lamp for at least 100 hours from new to stabilise the lamp ensuring consistent readings.
  • Repeat the tests more than once, preferably with different ballasts of the same type.

Testing Method

  1. Connect all equipment according to your manufacturer’s instructions.
  2. Ensure the power socket is switched off and plug the energy meter into it.
  3. Plug your ballast into the energy meter.
  4. Connect the reflector and lamp to the ballast.
  5. Turn the power on; allow the system to warm up for at least 30 minutes.
  6. Select the power setting (Watts) on the energy meter and then when the value is stable, make a note of it.
  7. Select the ‘Volts’ setting and make a note of the value. This can be any value from 216V to 255V, but usually it is somewhere around 240V in mainland UK.
  8. If your voltage reading was not 240V, you need to adjust it. As a rule of thumb, for each volt difference, adjust your power reading by the same value in percent. Here’s some examples:
    • If you recorded a voltage reading of 237V, this is 3V under 240V, so to compensate, you would apply 3% extra to your original power reading. If your original power reading was 630W, with an extra 3% applied this becomes 649W.
    • If your voltage was 242V, this is 2V over 240V so you would subtract 2% from your original power reading. If your original power reading was 630W, with 2% less this would be 617W.
  9. A properly performing 600W ballast will give a reading of approximately 655W.
  10. Preferably, repeat the above steps on more than one ballast of the same type and take an average of your results.