I have one of these hot beads, haven’t used it yet as i am not sure if there is a problem with it or i am not using it properly. Seams straight forward. Connect 12V either direction. Make sure there is enough amperage (ATX power supply) and the bed should get hot. Its not doing that. I have tested this with 2 power supplies and 1 car battery. It doesn’t get hot only the connecting wires do. I check the resistance with 2 meters and both say 0 ohms. Specs say 1.2 ish. Seems there is a direct short. I looked for a bridged trace under a glass but did not find anything. Is there something i am missing or is the board defective?
There is probably a short. Inspect it closely. It should be from 0.8 to 1.4 ohms. Make sure you use large gauge wires or multiple wires.
I used an ATX power supply and tied all the 12v wires together as well as the grounds so there was enough wires to hold the current, the ATX supply shut down due to a short. I searched for a bridged trace but could not find one although it is some what hard to see due to the red color.
Here is what i did. Scene the board didn’t work i decided it couldn’t hurt to start probing to find the short. I found it at the last 3 traces. I cut the trace to make a break. Now i connect 12v from the ATX and the bed gets hot. The resistance is still within specs. Now i have a working board.
i have heard that some of the cheap chinese clone ones connect the vias near the input pads to the ground plane on the back, shorting it out.
@Jason_Richardson I checked that and that is exactly the problem. I new it was close to the " left " solder pad but now when i drilled out the via the short went away. Thanks to your info.
merci pour l’info
If your meter is reading 0 ohms then you have a bridge somewhere near the terminals, period. Not sure how you could have a bridge unless the board trace was done wrong. You could always check resistance from one of the terminals and then along the trace every couple of inches. If you have to scrape off some of the coating to get a reading on the copper, just paint over it with something suitable when you are done. Or send it back for another one.
That’s what i did was probed the bed and found the short. It ended up being in the via as per @Jason_Richardson
Thanks for the post, I have one of these I have not tried yet, will have to remember these points when I do!
Hope it helps you. I have ordered a silicone heat bed. If i would have figured this out before i would of just used it instead.
We use this heated platform, much better and tested before delivered: http://www.panucatt.com/product_p/hbp200.htm
While i am confident that heatbed is better. The price is going to through people off. Theses China heatbeds are $13 including shipping.
Test the resistor and check if about 1.0+ ohm, please notice if the resistor value is too small with destroy your mainboard. I usually use 12v power supply with 350w for reprap machine.
I also make this heated bed 214214,314214,328328mm size, for building size 200mm, A4 size, and 300300mm.