Edge 1800W Subwoofer Amplifier IN4007 Diode Keeps Blowing up. - Page 1
Forum section: electronics / repair

author: MicroHero
author_rank: Newbie
timestamp: October 01, 2018, 12:00:06 pm
content: H,I bought an Edge 1800w twin subwoofer and it worked for a good few months. One day I had to swerve out of the way of an accident and there was a huge bang came out of the subwoofer. I opened up the amp and saw that a IN4007 diode had completely broken, thinking this was the issue I bought a couple off ebay and proceeded to solder 1 in place. The Subwoofer was working again but after about 30 mins of driving it just cut out (No bang this time) I have resoldered this about 4 times now with each time it breaking. I have noticed that the solder around the diode seems to have been melted during use causing the diode to become loose as well as it blowing up.Nothing on the board visibly looks damaged and I have a new multimeter on the way to check voltages and currents. I am still hunting but cant find a schematic for the amplifier but when I get it opened up again I can upload a picture of the 2 boards within it.Is it possible that a Chip is malfunctioning or another part is busted (Just not visibly)Thanks

author: madires
author_rank: Super Contributor
timestamp: October 01, 2018, 01:33:44 pm
content: A lot of components sold via eBay are fakes or relabeled parts with lower specs. I'd recommend to buy from a known distributor. Are you sure that the diode is an 1N4007? They are rated for 1A and 1000V reverse voltage.

author: MicroHero
author_rank: Newbie
timestamp: October 01, 2018, 01:47:08 pm
content: The Board is labeled saying IN4007 so I'm pretty sure that's correct. I'll see if any local sellers have it and test that instead thanks. Is it possible though that a chip is drawing too much or there is a faulty cap?

author: madires
author_rank: Super Contributor
timestamp: October 01, 2018, 02:13:52 pm
content: Yes, anything powered via the 1N4007 drawing more than 1A continuously would blow/overheat the diode. Without a schematic you have to figure out the purpose of the diode first as starting point for further checks.

author: MicroHero
author_rank: Newbie
timestamp: October 01, 2018, 02:47:16 pm
content: I'll be getting a multimeter soon so I can test the chips. It is in line with a chip so i assume it is to protect it

author: madires
author_rank: Super Contributor
timestamp: October 01, 2018, 02:51:54 pm
content: Which chip and which pin? We could check the chip's datasheet meanwhile.

author: MicroHero
author_rank: Newbie
timestamp: October 01, 2018, 03:00:16 pm
content: I'll be home in 2 hours roughly so I can get pictures and the chips details then

author: abraxa
author_rank: Frequent Contributor
timestamp: October 01, 2018, 07:01:47 pm
content: Since it all started when you swerved, I'd assume that there was something loose inside the amp and caused a short when landing. Please also inspect the board for any "out of place" solder blobs or metallic parts like clamps, washers or screws. I'd be surprised if there are any burn marks but if you see any then that's worth noting.

author: james_s
author_rank: Super Contributor
timestamp: October 04, 2018, 03:50:42 pm
content: Without seeing the amp or schematic I can only guess, but check that all of the power devices are properly insulated from the case. Usually they have silicone rubber thermal pads.