LED lighting fixture driver busted – what can I replace it with

ledlight-fixturelow-voltagepower supply

A LED lighting fixture in my apartment (in Israel/Palestine) started flickering for a while before coming on, then went bust. I suspect it's the driver/power supply rather than the LEDs themselves, since it was all very uniform.

the LED area cover has a sticker saying "9V DC 40W 196 LEDs".

Question: What can I replace this driver with?

That is, what tolerance ranges do I have for the different driver parameters, to fit my LEDs?

The supposed manufacturer's website (www.xz-power.com) gives me an HTTP 403 page, "Your request was rejected", so no help there. There's this webpage with a list of what are supposedly the manufacturer's products, but – I'm not sure I know what to look for; plus, I'm not sure these things are available in single units for retail where I live (in fact I doubt it).

Notes:

  • I'm not sure the driver was the right one to begin with, seeing how it failed. I didn't buy this fixture myself.
  • I'm not asking for specific product recommendations.
  • I don't care about how much such a driver would cost – for the purposes of this question.

This is the sticker on the driver:

enter image description here

Best Answer

That's crazy, there's another thread using the word "driver" to talk about a constant-voltage LED power supply, and now this thread using the word "power supply" to talk about a constant-current driver. Marketing is funny lol.

The sticker on the LED cover is mistaken. The driver labeling contradicts it, and the driver is far more likely to be correct, since the lamp did work.

The ruling figure on this driver is SEC: Constant current: DC540ma. This is a 540 milliamp driver designed to output exactly that current (at whichever voltage that happens at). This voltage is decided by the LED characteristics.

However, the driver is not magical; and is only electrically tuned for an output in a certain voltage range. That is specified next: 30-56 volts, with 60V an absolute max. Further, it has a maximum power output of 31 watts, which jibes with the 56 volts.

LEDs work at best performance when driven at constant-current. They are not ohmic, and cannot "work as their own resistors" the way an incandescent bulb can. (that was the hardest part about designing incandescent bulbs; Edison had no access to constant-current power supplies (though Tesla did, because of AC).

So, the replacement driver you need has

  • An input voltage within 220-240V (whatever your AC mains power is in your country)
  • An output current of 540ma on the button. (or slightly less, but that will mean proportionately less light)
  • An acceptable output voltage range of - well, whatever your lamp actually needs, but clearly that is between 30V and 56V.

Noting that your driver module has a "TUV" logo, that means whoever built this lamp actually complied with quality standards and used a driver approved by an NRTL (Nationally Recognized Testing Lab) - a list maintained by USA's OSHA, but that is considered the gold standard worldwide for reliable suppliers. The "CE" logo is not enough.

I would shop for drivers at mouser.com, Digi-Key, etc. Avoid at all costs the cheap Cheese junkstream coming out of Shenzhen.