behnt: Should work, but you won't have a headed bed output (that needs more current than the 5A input can provide, plus the FET will not be well cooled), unless you switch it through something like a SSR. mkelly: if the heater is 1.1 ohm, at 24V that's closer to 22A, and possibly more at startup/cold. Note also that SSR's need to be mounted on a heatsink to handle their full current capacity. Alby Cefiar - RAMPS Electronics
QuoteMogal Does CNCZone.com have too many sub forums If you build it, they will come. IMO, yes! Plus a very confusing forum system that is just impossible to follow sometimes. I've been using web forums since 1998, the Internet (though not in it's current form) since 1993, and computers since 1982, and to me it's a complete and utter mess of a site that has no meaning. Please do not mentionby Cefiar - Administration, Announcements, Policy
QuoteNewPerfection Do we have enough posts to go into each of these sub-forums? We already have a few too many sub-forums as it is. Maybe it's time to consolidate some of the other forums that aren't doing too much? Some of the existing forum names could probably be modified to be a bit more inclusive, so that it's more apparent what is referred to. Here's some (tentative) examples on what cby Cefiar - Administration, Announcements, Policy
The problem there is that while the MCU itself on boards like the Mega and Due has a separate ground for the analog inputs, the boards (such as the Due and Mega) have one common ground plane for everything. And if you get a decent current through any ground pin to the ground plane on the Due/Mega, it changes the readings. On a Mega it's not so bad as your Max reading is 5V, whereas due to the lby Cefiar - Controllers
It's just a display to drive. Electrically it's easy. That said, the main issue is that the firmware is already fairly big, an driving an OLED display from an 8-bit Arduino with its limited memory/flash is going to be an issue. Things like fonts, graphics, etc take a lot of room, more so the bigger the display. I don't expect to see an OLED display working well on a printer with an 8-bit Arduinoby Cefiar - Controllers
Apparently it's become a common fault on the board that the track that provides this power (getting it externally from a shield) either dies/breaks or is just not connected. See this post: Note: The same could happen with cheap Arduino clones, having the track on the Arduino broken, so you really want to see if the issue is on the RAMPS board or the Arduino. Use a multimeter and measure the voby Cefiar - RAMPS Electronics
QuoteTraumflug This ground loop thing is right, but ignoring the shield doesn't help, you get the loops through the data lines anyways. In fact, I found connecting the housing to GND to be neccessary even in my low EMF environment. Depends on where the link is. On some PC's, there is no link between AC earth and DC ground, and the PSU expects them never to be in contact. If the USB shield getsby Cefiar - Controllers
Will only make one suggestion: Make sure that the USB connector shield is NOT connected to ground by default. Provide a jumper for this purpose (if people want it), but don't make it hard wired. A lot of these development boards (Arduino, ARM boards, etc) have the USB shield and USB ground tied together. If you use the USB for power, this is fine but as soon as you add another mains PSU to runby Cefiar - Controllers
I've tried pinging bobc by email but not gotten any response. :/by Cefiar - Controllers
QuoteBuback Why, exactly, do we even need to host forums for lots of different electronics? or softwares? Shouldn't they have their own communities and forums? why not just pick one, and then support that one here and refine it until it's perfect, and switch when something better comes along (determined through votes, i guess, or by fiat, if someone is ballsy enough) Many of the electronics outby Cefiar - Administration, Announcements, Policy
ufab: It should be fine to do that. Just note that the standard design of RAMPS has the power routed through a diode internally, so obviously something is wrong if this isn't working. That may mean you haven't populated the board with this diode (as you're using > 12V), but it could mean your Arduino Mega OR your RAMPS board has a fault. Running direct power may bypass the fault, or it may maby Cefiar - RAMPS Electronics
As someone who only reads parts of the electronics forums (the general one and the ones I'm used to dealing with), I personally don't want to have to go looking sorting through lots of other messages about other types of electronics to answer questions about various stuff. Some consolidation is in order (we could collapse a few forums together), but collapsing electronics into just 1 forum is maby Cefiar - Administration, Announcements, Policy
I don't have the adaptor. I was however involved with bobc on the design of the RAMPS-FD board, and the voltage trigger reason was why we use 74HC or 74AC parts elsewhere on the board (to go from 3.3V to 5V).by Cefiar - Controllers
This is getting out of hand, and I think a Mod needs to step in and do something. See - Specifically his last post. To quote from the last post (at time of writing this): QuoteShawnT98027 Three things... that is my purpose as a contributor. To help one person a day actually fix their printer/prints (rather than like a lot of posters with less knowledge and understanding; that lead the unknoby Cefiar - Administration, Announcements, Policy
Ahh. your PC PSU may not have the same reference ground as your printer electronics PSU might, especially if both are grounded to AC. If your PC's DC ground rail is some voltage different from the AC ground (eg: 3V), while your Printer PSU has a different voltage difference (eg: 1V) between AC and DC ground, then you can run into trouble when you plug in a USB cable. The "loop" here is that ACby Cefiar - RAMPS Electronics
I would stick to a 74HC or 74AC chip. A 74LS chip running on 5V may not see 3.3V high voltage as "high", whereas a HC/AC chip should.by Cefiar - Controllers
One thing you need to beware of: You can change the fan output to use it, but you need to make sure NOTHING ELSE in the config is using those pins. If you find that, you need to swap the pins about or list the unused pins as -1.by Cefiar - RAMPS Electronics
I've seen this sort of issue before with Slic3r. If you're running Marlin or Sprinter, you can limit the max speed of the extruder there. This doesn't solve the Gcode, but it does at least solve the issue.by Cefiar - Slic3r
If you've got a 0.5mm or larger nozzle, a good thing to use when changing between ABS and PLA is Laywoo-D3 wood particle filament. I wouldn't try Laywoo-D3 in anything smaller than 0.5mm though - tends to clog. It will run at both ABS and PLA temps, so you simply leave your extruder at the temp you were using, push the Laywoo-D3 through (to remove all your old plastic, then as soon as you get cby Cefiar - Controllers
How hot the MOSFET should get depends on a lot of things. Do you have the spec or part # of the MOSFET you used to replace the one on the RAMPS board? Not all MOSFETs are good fits for this setup - you simply can't just replace one with another unless it's suitable. Also, you should have a fan (eg: a small 40-60mm in dia fan) that is permanently on/running, pointing at your RAMPS board, as the Mby Cefiar - RAMPS Electronics
The 9 refers to the Arduino Mega pins.. If you trace the circuit, you'll find that D9 on the Arduino is the middle FET output. This is used as the FAN to blow on the extruder if you select board type 33. Look at the schematic for the RAMPS 1.4 board (see the ramps wiki page), as the pins match the outputs from the Mega.by Cefiar - RAMPS Electronics
Buy a proper ISP instead. USB to parallel converters aren't a true parallel port, and so "bit-banging" the USB parallel port to program the 1284 (or any chip) won't work. There's are a whole heap of cheap USB ISP's available from companies like Freetronics (in Aus), Little Bird Electronics (in Aus), Sparkfun or Adafruit. Note: I help maintain the forum for Freetronics - though I don't actuallyby Cefiar - Australia, Melbourne RUG
One of your motors is either: 1. Faulty (could have been damaged in transit, by being dropped on its shaft, or by something getting in the bearings such as metal filings). 2. Different to the other (they must be the same spec in all respects). Try each motor individually, and with any luck you will find one doesn't move the amount you have specified it to move, which would indicate it's faultyby Cefiar - RAMPS Electronics
The one thing that an ATX PSU has over the basic design that you're looking at is AC-DC conversion efficiency. Switch mode supplies, such as an ATX supply, can be very efficient (>90%, depends on design), whereas your more traditional PSU will most likely be well below that. Also, unless you have a decent transformer on hand, you may find that your PSU will end up costing a whole lot more. Tby Cefiar - Controllers
To go to the latest post, click the red flag. If you click the post title, it will take you to the first post. If the last message was spam and gets deleted, the red flag will stay there (which is annoying, but so is spam).by Cefiar - Administration, Announcements, Policy
I think he means he's measuring the RAMPS board inputs the thermistors connect to. Hopefully he did this while the board was off, as this in itself could damage the thermistor inputs.by Cefiar - RAMPS Electronics
Do you see a temp listed for the heatbed? If the thermistor for the bed is not connected, or if it's too cold (below about 15 C, somewhat thermistor dependant), it won't turn on the bed as it suspects there is no thermistor (and won't know when to turn it off).by Cefiar - RAMPS Electronics
leadinglights: I would check the motor itself. You may find that it has a bad winding or that at some place in it's movement it shorts out somehow (ie: not all the time, so usually you don't hit it). That's about the only thing I would think that would cause such a problem. FWIW: Such motor faults are also quite capable of being the culprit for losing steps, and very hard to track down sometimesby Cefiar - RAMPS Electronics
Were you measuring between both terminals of D10/D8 or from one terminal and ground? You need to measure from one terminal to the other. The FET's switch the ground line, so the switched line will ALWAYS read 0 (either not connected, or shorted to ground).by Cefiar - RAMPS Electronics
You may have fried the regulator on the Arduino Mega. Note: Do NOT plug in the PSU to the RAMPS board for either of the following tests, and make sure USB is also disconnected. I would try removing RAMPS from the Mega and powering just the Mega via the DC barrel jack from a plugpack. If that doesn't work (no lights), the on-board regulator on the Mega is dead. If it does work, unplug the plugpby Cefiar - RAMPS Electronics