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  1. T

    Question about technical limitations of 12v relay switches

    Hi, I'm new here, I've just started a project that has me building an electrical circuit for the first time and I don't really know what I'm doing! I'm hoping someone can answer a quick question. I have a 12v electric motor (has two power levels, at 9A and 20A and it was suggested to go with a...
  2. R

    Battery powered COB LED illumination drop off

    PROBLEM: 24 SMD COB LED has too much illumination drop off over 3 hours. Currently powered by four 3V button batteries. PREFERRED SOLUTION: Get this battery powered LED to perform more consistently over a few hours. THE STORY: I’m working on a little project at home for a custom...
  3. K

    Circuit of the switch 12v. led-lighting

    One Bit Switcher I offer my own version of the circuit of the switch 12v. led-lighting for the kitchen based on the dual trigger of the hc74 chip. Created with EasyEDA.
  4. mbkitmgr

    Does this animal exist - Automotive 12v multi-channel relay

    By my post you will gather I have very little electronics experience. I am trying find a specific black box so please accept my apologies for the inaccurate descriptions/terminology. I own a Can-Am Spyder made by a Canadian company to which I have fitted their tow wiring harness kit to supply...
  5. J

    AAA NiMH Backup Battery Pack for 12V Automotive Use

    I have been asked to play a role in the design of a 12V backup battery pack that would be used to backup a vehicle security system and siren in exclusively AUTOMOTIVE applications. I have general electronics experience but no experience with the design of a battery backup system, and the...
  6. Vizier87

    Repairing a UPS backup power supply

    Hi guys, It's been a while. Before I actually buy a UPS backup supply, I need some advice and potentially save more than 50 dollars. I found one from a friend (APC ES 500). Naturally, it was already dead. I've hooked it up to the mains and no indicator LED or anything turned on. Dead as a...
  7. S

    Help!!!!!, Relay in motorcycle 12V environment,

    Hello, I was hoping some can help me figure if i can use SRD-12VDC-SL-C, to turn may parking light into blinkers. Here is the issue; I purchased aftermarket blinkers for my motorcycle, these only light up while blinkers are turn on, making you less visible during regular operation. Hence...
  8. F

    Running multiple 12v motors of one PWN controller (help required)

    Hi there, First off a bit of background, this is part of a university project where I want to control the flow of water from a reservoir into 12 small tanks (the flow going into each of the 12 tanks needs to be the same, roughly 30ml/min). My way of achieving this is to use 12 peristaltic...
  9. S

    Is this Application Report Wrong?

    I have been looking into back-flow protection for batteries and chargers and invented this wonderful circuit, and as usual when you search you find that it has all been done before. Just so in this case and the circuit in Figure #5 of the application report linked below, not only uses a similar...
  10. J

    12v rail for work bench needs battery what kind of controller I need?

    Basically to power various lights and e4c im setting up something similar to a 12v outlet around my workbench, I also want to power a 24v fridge. Problem is that the 6-8A Spike when it first turns on is too much even though the psu is 15A and I've gotten it to 13A ok. I'll have a battery hooked...
  11. M

    Portable power pack

    OK so I'm after a bit of wisdom here, I've built a portable power pack for camping, fishing, festivals etc and am struggling to understand the ah and how many charges I should be getting out of it etc so here's a couple of questions I was hoping you guys could help with . . So its all wired up...
  12. budget minded

    12v bicycle trailer sound system details

    this isn't exactly an "automotive" etc. application, but it will be a 12 volt system, just lacking an alternator. there are a few issues i need to iron out though. it was originally supposed to be a 36v system, but that created a lot of problems eg. separate batteries for an EQ/crossover or...
  13. F

    12v output or 24v output???

    Likely a silly question for the rest of you, but something I need to know and don't know now. Working with a 12 volt automotive system, if you were to tie into EACH of the two brake light power supplies (right side and left side - perhaps about 6 inches back from the actual brake light...
  14. D

    12v led turnsignals

    Hello, I searched around the forum, and didn't find anything that would help me with a project that I have going on. I purchased some LED strips that I am going to install on my car. The issue is that they are dual color, white and amber. The white is a running light, and then the amber is the...

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