Two (major) issues: - you must have a dummy load on 5v rail (10Ohm 5W resistor) - otherwise supply will be unstable and may broke quickly - no "sudden smoke" - you have a huge load (amperage) on the heated bed, you should use two pairs per rail for power supply - at least for the hotbed - it will reduce heating of the power cables - this is for your own sake Minor: - it is good idea to connect ATX power to RAMPS - this will allow you to automatically switch machine after print - much more secure for longer prints - using connector from the graphics card (4 or six pin) and Big Atx connector - it is quite simple to build same circuit without need to cut anything from ATX power supply - you can keep your guarantee (costs of additional materials is less then $2 or zero if recovered from old PC)
Needing load on the 5v rail is NOT true for all PSUs (I have two different PSUs running perfectly stable with nothing on the 5v rail), but certainly wouldn't hurt.
Good tutorial on using ATX supplies. A few things though. Some supplies may need a load on the 5v line to regulate properly. Something like a 10 ohm 5w resistor across a red and black wire should be enough. This may be old information, but I did need it on an old supply I had. Also I don't like the idea of using only two pair of those 12v wires. I think they are good for a few amps each, but running 10A though just one pair for the heat bed you will lose some voltage. I gathered ALL the yellow and black wires from the supply. Aprox 2/3 of them I used for the heat bed wiring, and the rest for the motor/hot end wiring. You can fit two or three of those wires twisted together in one terminal of the ramps board. Actually a better idea would be to unsolder that connector and use one of the 4 pin molex connectors on a fly lead off of the ramps board. I also put some 3AG fuses in series with the wires so as not to rely only on the thermal fuses on the ramps. I also opened up my supply and trimmed all the unused wires close to the circuit board. The RAMPS board has a connection for going to the ATX switch wire. If you power the Arduino from USB you can have the firmware turn the 12v supply on and off. There is also a 5v always on connection from the supply that you can wire up to the Arduino 5V in (the Gen 7 electronics board can use this wire).
So basically if you don't cut off the plug and use a jumper on the Green to Black, you don't need to mess the Orange to Orange and Brown to Black connections. I know you were trying to neaten up the PSU appearance but technically its not necessary. The ATX supply I just purchased has a 6-pin PCI-E that plugs directly into my Printrbot Simple's board and I'm more interested in having my printer perform well. I have a modified Xbox 360 power supply, and like an idiot(I'm new to this 3D printing stuff) I followed directions and connected all the Yellows and all the Blacks and connected the Red to the Blue. I tried and succeeded to tie the Black and Yellow leads to a male connectors positive and negative terminals and it was getting hot. A request put in to Printrbot's customer service proved my newness and stupidity when he told me that his Simple's are hooked up using the 6-pin PCI-E on the board. I upgraded my Simple with Matrix Precision's X, Y axis upgrade which extends the X & Y from 6" to 8" by using a solid Aluminum bed with a recess machined into it to fit an 8"x 8" heat plate I got from Printrbot. Sorry to ramble. This is my story and I'm stickin' to it.
This is the same as the ATX Power supply mod for the XBox 360. You've got major load (as many mention on here) on a very thin gauge wire ... did you set your house on fire yet? Smart is couple all 12V rail wire connections to a heavy 8 gauge wire (like the one stock came with the printer) and then that wire to the Ramps board. The load on the thin wire you have coming out of that PSU in this vid will heat up very quickly when you put a heavy current through it to heat your bed up, power your motors, run your Ramp board to drive the extruders, etc etc .
You skip over the wires at the end without giving a good look at stuff, but I think I understand the idea. It would be useful if you provided a wire diagram. EVERYONE has to connect that GREEN wire to a ground, and the wire is green for all ATX supplies. It seems that some of the other wires vary, but basically if you have two wires that are in the same pin, you need to connect those. It will be easier to find these if you cut the wires pin by pin instead of the entire connect like he does in the video.None of the other wires matter because they never make connections with anything. After using a jumper for my supply for the past two years I'm finally gonna wire them together and get rid of all the unnecessary cables.
So I did it. I first cut every unused wire that didn't have two in a single pin, then I put some heat-shrink insulation around the ends because I couldn't reach the end of it at the breadboard. I but some tape around the green and black wire and the orange and whatever was in the same pin with it (brown for mine) and the tape helped me keep track of it among all the other cut wires. Finally connected those wires and then closed it all up and it runs!
Just to add one thing about the capacitors, waiting a few minutes is not going to make a huge difference. They can stay charged up for weeks. Ff you're gonna disassemble it, you need to be careful not to touch them. However, you can easily discharge them by "shorting" them with a screwdriver (make sure you don't touch any metal parts on the screwdriver though).
You go through a lot of trouble hard wiring the PSU, when you could very easily get some ATX & PCI-E extension cables and create modular cables so you could easily just connect any ATX PSU of proper size to your printer without having to rewire it any time you want to change the PSU or control board. I wired mine this way, and it works beautifully. 8-pin CPU (2x-4-pin) goes to my heatbed MOSFET, 6-pin PCI-E goes to my MKS Gen, and ATX connects my 5VSB to my Pi and PS_ON to a physical switch on my printer. I can upgrade/swap PSUs or control boards in a matter of minutes.
ok i followed you video and check about 15 times before powering up and as soon as i did my mega 2560 was on fire.... what could have possibly happened...
Hello, nice video. I need some help. My psu has 2 oranges in 1 pin, and 2 red in another pin all the way across the atx plug. I don't have brown.what can I do? My major problem is , that, when I try to heat the heatbed after 3 sec the power supply turns off.(it is a 350w) Thank you
Well in my occasion , it was a problematic psu. I tried another psu and it was fine.I just connected the green with the black. Check your psu.You maybe have bad capacitors
Threaded rods I usually buy from McMaster. I prefer the zinc plated threads to stainless steel because the SS threads are softer and tend to be gummy. Smooth rods I buy in bulk online, but you can probably find them from a few sources. Ebay has many sellers that can hook you up, including me. Look for chrome plated ones, with a decent hardness rating (HRC60 or more).
A bit dangerous running your hotbed wires along the bottom of the hotbed. At 5·15 you see your wiring taped to the bottom of the hotbed. That´s a big NO NO
Two (major) issues:
- you must have a dummy load on 5v rail (10Ohm 5W resistor) - otherwise supply will be unstable and may broke quickly - no "sudden smoke"
- you have a huge load (amperage) on the heated bed, you should use two pairs per rail for power supply - at least for the hotbed - it will reduce heating of the power cables - this is for your own sake
Minor:
- it is good idea to connect ATX power to RAMPS - this will allow you to automatically switch machine after print - much more secure for longer prints
- using connector from the graphics card (4 or six pin) and Big Atx connector - it is quite simple to build same circuit without need to cut anything from ATX power supply - you can keep your guarantee (costs of additional materials is less then $2 or zero if recovered from old PC)
jerzyk007 How can I set up the circuit with the graphics card and the big pin?
Needing load on the 5v rail is NOT true for all PSUs (I have two different PSUs running perfectly stable with nothing on the 5v rail), but certainly wouldn't hurt.
Good tutorial on using ATX supplies. A few things though. Some supplies may need a load on the 5v line to regulate properly. Something like a 10 ohm 5w resistor across a red and black wire should be enough. This may be old information, but I did need it on an old supply I had.
Also I don't like the idea of using only two pair of those 12v wires. I think they are good for a few amps each, but running 10A though just one pair for the heat bed you will lose some voltage. I gathered ALL the yellow and black wires from the supply. Aprox 2/3 of them I used for the heat bed wiring, and the rest for the motor/hot end wiring. You can fit two or three of those wires twisted together in one terminal of the ramps board. Actually a better idea would be to unsolder that connector and use one of the 4 pin molex connectors on a fly lead off of the ramps board. I also put some 3AG fuses in series with the wires so as not to rely only on the thermal fuses on the ramps. I also opened up my supply and trimmed all the unused wires close to the circuit board.
The RAMPS board has a connection for going to the ATX switch wire. If you power the Arduino from USB you can have the firmware turn the 12v supply on and off. There is also a 5v always on connection from the supply that you can wire up to the Arduino 5V in (the Gen 7 electronics board can use this wire).
Yeah Power Good ...that on old power supply
So basically if you don't cut off the plug and use a jumper on the Green to Black, you don't need to mess the Orange to Orange and Brown to Black connections. I know you were trying to neaten up the PSU appearance but technically its not necessary. The ATX supply I just purchased has a 6-pin PCI-E that plugs directly into my Printrbot Simple's board and I'm more interested in having my printer perform well. I have a modified Xbox 360 power supply, and like an idiot(I'm new to this 3D printing stuff) I followed directions and connected all the Yellows and all the Blacks and connected the Red to the Blue. I tried and succeeded to tie the Black and Yellow leads to a male connectors positive and negative terminals and it was getting hot. A request put in to Printrbot's customer service proved my newness and stupidity when he told me that his Simple's are hooked up using the 6-pin PCI-E on the board. I upgraded my Simple with Matrix Precision's X, Y axis upgrade which extends the X & Y from 6" to 8" by using a solid Aluminum bed with a recess machined into it to fit an 8"x 8" heat plate I got from Printrbot. Sorry to ramble. This is my story and I'm stickin' to it.
This is the same as the ATX Power supply mod for the XBox 360. You've got major load (as many mention on here) on a very thin gauge wire ... did you set your house on fire yet?
Smart is couple all 12V rail wire connections to a heavy 8 gauge wire (like the one stock came with the printer) and then that wire to the Ramps board. The load on the thin wire you have coming out of that PSU in this vid will heat up very quickly when you put a heavy current through it to heat your bed up, power your motors, run your Ramp board to drive the extruders, etc etc .
You skip over the wires at the end without giving a good look at stuff, but I think I understand the idea. It would be useful if you provided a wire diagram. EVERYONE has to connect that GREEN wire to a ground, and the wire is green for all ATX supplies. It seems that some of the other wires vary, but basically if you have two wires that are in the same pin, you need to connect those. It will be easier to find these if you cut the wires pin by pin instead of the entire connect like he does in the video.None of the other wires matter because they never make connections with anything.
After using a jumper for my supply for the past two years I'm finally gonna wire them together and get rid of all the unnecessary cables.
So I did it. I first cut every unused wire that didn't have two in a single pin, then I put some heat-shrink insulation around the ends because I couldn't reach the end of it at the breadboard. I but some tape around the green and black wire and the orange and whatever was in the same pin with it (brown for mine) and the tape helped me keep track of it among all the other cut wires. Finally connected those wires and then closed it all up and it runs!
Just to add one thing about the capacitors, waiting a few minutes is not going to make a huge difference. They can stay charged up for weeks. Ff you're gonna disassemble it, you need to be careful not to touch them. However, you can easily discharge them by "shorting" them with a screwdriver (make sure you don't touch any metal parts on the screwdriver though).
You should try using ferrule crimps
You go through a lot of trouble hard wiring the PSU, when you could very easily get some ATX & PCI-E extension cables and create modular cables so you could easily just connect any ATX PSU of proper size to your printer without having to rewire it any time you want to change the PSU or control board. I wired mine this way, and it works beautifully. 8-pin CPU (2x-4-pin) goes to my heatbed MOSFET, 6-pin PCI-E goes to my MKS Gen, and ATX connects my 5VSB to my Pi and PS_ON to a physical switch on my printer. I can upgrade/swap PSUs or control boards in a matter of minutes.
ok i followed you video and check about 15 times before powering up and as soon as i did my mega 2560 was on fire.... what could have possibly happened...
Does this work for the anet a8? I see you have a board I've never see before, it is confusing me.
how you adjusted the current rating .... because ramps board requires 5amp and 11amp for supply pins..
Amps are drawn, not provided.
Hello, nice video. I need some help. My psu has 2 oranges in 1 pin, and 2 red in another pin all the way across the atx plug.
I don't have brown.what can I do? My major problem is , that, when I try to heat the heatbed after 3 sec the power supply turns off.(it is a 350w) Thank you
Yeah. similar for me too. He goes by that part rather quickly with no good look at the connector.
Well in my occasion , it was a problematic psu. I tried another psu and it was fine.I just connected the green with the black. Check your psu.You maybe have bad capacitors
will this setup work for a heated bed ?
How do you wire a p8 configuration?
Marty, may I know where did you bought the hardware like the threaded rods and smooth rods from?
Threaded rods I usually buy from McMaster. I prefer the zinc plated threads to stainless steel because the SS threads are softer and tend to be gummy. Smooth rods I buy in bulk online, but you can probably find them from a few sources. Ebay has many sellers that can hook you up, including me. Look for chrome plated ones, with a decent hardness rating (HRC60 or more).
What printer is that?
A bit dangerous running your hotbed wires along the bottom of the hotbed. At 5·15 you see your wiring taped to the bottom of the hotbed. That´s a big NO NO
I would tin all my ends
Do NOT tin wires that go into screw terminals. One of many sources: reprap.org/wiki/Wire_termination_for_screw_terminals