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I understand "nuts and bolts" but "amps and volts" evade me....
Power supply replacement... Can a 12V/20A/250W power supply be replaced with a 12V/30A/360W power supply? My guess is that the answer is yes because my understanding is that the higher rated power supply is just that, it can provide more under load than the lasser one.
Yes, it will be fine.
Thank you Mjolinor.
My only hope now is that I didn't do other damage. I was working way to late and dog tired on my new project. Went to plug PS in to controller board.... reversed polarity... and heard a tiny little pop. Not like, BANG!... about as loud as a toothpick hitting the floor. That was enough to some damage to something. The PS wont light up and I get no voltage across the 12V rail. Hope I am not looking at a new control board now, too.
Plugging it in reversed polarity should not have damaged the power supply. It may have damaged the controller board. Look for a fuse somewhere on the board or a circuit breaker on the power supply. If the controller board is shorted or otherwise damaged, the power supply may be shutting down to prevent damage to it or worse. Some power supplies won't turn on unless they get a good signal from the computer.
What type of control board do you have? Saying it is fine could be optimistic without knowing that and someone looking at the design for that board. For example, RAMBO would have burned open fuses. RUMBA is probably OK. With RAMPS, I'm not sure about the bed heater MOSFET - RAMPS has no reverse voltage protection built into the 11-amp input. Can't speak to other boards.
The board, Anet 1.0 took no damage. The stock power supply is dead. The power supply was replaced with another of slightly better output capability. The printer is running very well.
psu's have loads of failsafes.
I've had them literally blow up and not damage the motherboard in a pc.
And when one of the big inside capacitors the size of a c-cell battery blows - you know about it !
Particularly if your head happens to be round the back at the time.
Then I don't think plugging it in backwards was what did the damage. Plugging in the power supply backwards would not have damaged the power supply. How could the power supply be damaged by that? It was already dead.Quote:
Originally Posted by lawndartleo
Let me clarify before putting this to bed...
Power supply was wired correctly and plugged into the wall correctly. Sleepyhead then proceeded to plug into the controller board with polarity flipped. Amazing things you can do with idiot proof connectors when you are dog tired. It's not like I fully jambed the connector down on the board terminals but I got it together far enough that the pins made contact and POP! Not even a loud pop but enough for me to utter a few obscenities as I realized I had done something wrong. The power indicator on the PS went out and has stayed out since. No voltage across the outputs at all, anymore. It's dead.
I found a slightly better PS on Amazon, equal output voltage, slightly better power and an integrated fan. A few extra holes later in the printer frame and I am up and running just fine.
The walkaway here is don't work on stuff just to get it done. Go to sleep, come back clearheaded and do it right. I cost myself $25 bucks and an extra week of build time to get going.
PS... yes I know that plugging a hot power supply into the controller was stupid as well. Again... fatigue and a desire to just finish a project lead me into a bad decision making loop. When I did what I did, something was going to pay the price.
The replacement power supply would be fine. As long as it has an equal voltage it would run fine. Better have an voltage regulator so it won't be damage by a power fluctuate from the power utility.
12v is the voltage, this is what matters most--too much will fry your board, too little won't work.
30A is the amp RATING: it's the maximum amps that the power-supply can provide without burning out.
360W is redundant information. Watts are just amps * volts. It's a shorthand to quickly describe how powerful a supply is, but you can just do the math yourself: 12x30 = 360.
The best way I've found to explain volts, amps and watts is to think of electricity like water flowing through a hose.
volts = how fast the water is moving through the hose
amps = How thick the hose is
watts = how much water is coming out the end of the hose (a function of how fast the water is flowing and how thick the hose is).
If the water isn't moving fast enough (volts) there won't be enough force to make your machine work.
If the hose isn't big enough it will burst if the machine trys to draw more water than can fit in the hose.
Your comparison is wrong.Quote:
Originally Posted by djprinter
Volts is nothing to do with anything flowing, it is the pressure that can make it flow. Like a loft tank in your house the voltage is the height of the tank whether any is flowing or not. That is made clearer when you call it "potential difference" rather than voltage. Amps compares to the amount of water flowing.
All forms of energy can be compared to each other, they all have equivalents whether it is a tank of petrol, a tank of water, a battery or a gas supply.
It's an analogy, and all analogies are imperfect. Using the speed of water moving is a good description for volts in an active electrical circuit, using your example of potential energy is a good description of a resting battery.Quote:
Originally Posted by Mjolinor
In this discussion we were describing the former not the latter.
Amps relates only to the "amount" in a single moment, not the amount over time.
The analogy is wrong. You can have voltage with no flow. The correct analogy is that of the "head" of water. A water tank full of water at the top of a building even though the tank has no holes still has the potential to deliver energy as does a battery that has no wires, the potential is there and not tapped.
As I stated there are direct comparisons of equivalents across all energy delivery systems, tehy are more than analogies the are different versions of the same thing.
Maybe some diagrams will help you understand:
http://hyperphysics.phy-astr.gsu.edu...c/watcir2.html
wow...so many info............!!!!!!!!!!