completed MK 3 S+ Kit No Power  

RE: completed MK 3 S+ Kit No Power

Have not built my mk3 yet, but would suggest you go back over all your connections to psu and board and make sure all them are correct way round and properly tightened/seated.

PSU is auto negotiating for 110/220v so you are OK from that respect.

Also check the fuse in the mains lead has not blown.  Can get a weak fuse on occasion. 

All else fails go onto chat and speak to prusa direct, could have a bad psu.

RE: completed MK 3 S+ Kit No Power

I would go back and check the two 24 volt connections coming from the black PSU (box on the right), then check all connections to the Einsy board to make sure you made the connections (easy to forget some) and that the connections actually went to the correct place.  If you think you have no power, do check that you have voltage coming into your PSU - e.g. make sure it is plugged into a socket that you can prove has power.  Then check that the switch on the PSU is turned on.  With the PSU turned on, measure the voltage across the red-black wires at the bottom of the PSU.  There are two wires, ++, so using your volt meter, check for power.  Anyone with a kit 3d printer should have a volt meter lying around.

Once you have confirmed the PSU has 24 volts, check all of the leads from the control panel back to the einsy board.   You're looking for things that have come unplugged.

Does the light in the power switch light up?

RE: completed MK 3 S+ Kit No Power

I agree with these steps to check things.

But my MK3s doesn't have a light in the power switch. Not sure if the + has that light.

RE: completed MK 3 S+ Kit No Power

Come to think of it - not sure if the PSU switch is lighted (though my brain says yes).  Since you have to take the protective cover off of the side of the PSU to check the voltage, there is a light on the board that does light up - it's under that cover - I am positive because I just added a LED bed light to my printer on Sunday - and had to have that cover off.

Another thing to eliminate - the power cord itself.  It's a standard cord - same one used for monitors and desktop computers.  See if swapping out another cord helps you get power.

RE: completed MK 3 S+ Kit No Power

Some time ago I read on here that someone had a problem with the power cord being a very tight fit. He had to really push it in hard to make a good connection.  Swapping the cord is an easy test. (if you have one ofcourse)

RE: completed MK 3 S+ Kit No Power

Posted by: @dan-rogers

Come to think of it - not sure if the PSU switch is lighted ...

Just checked my MK3S+ and the PSU switch is not lighted.  So the only way to tell will be measure voltage output.

RE: completed MK 3 S+ Kit No Power

There is a light on the bottom of the psu. under the prusa plastic ,  its not lit.

i pulled the cover on the power supply, confirmed line power thru the switch and confirmed no power at the 24 volt output.

i assume that that when i pulled the power panic plug there would be no control of the psu and i should have 24 volts at the output.

RE: completed MK 3 S+ Kit No Power

Thanks for the help.

I pulled the wires of the psu and the light came on.

checked the wires to the controller again and discovered i landed one of the wires in reverse.

Reworked the wires and its all good now

Thanks for everyones input

RE: completed MK 3 S+ Kit No Power

Ask a silly question, is there a glass fuse inside or next to kettle plug on these psu units?

RE: completed MK 3 S+ Kit No Power

I would have measured with the power panic connected.  I would look for a fuse.  There is a fuse on the einsy board - I have not looked for a fuse on the PSU.  If your PSU is bad, I would contact tech support - which is done via the chat in the e-shop.

RE: completed MK 3 S+ Kit No Power

@dan-rogers

At least on my PSU there is a fuse holder, right above the socket for the wall, I'd take a guess that if all else is good, its either a dead fuse or dead PSU, but make sure to check what others have outlined.

RE: completed MK 3 S+ Kit No Power

Posted by: @ikith

@dan-rogers

At least on my PSU there is a fuse holder, right above the socket for the wall, I'd take a guess that if all else is good, its either a dead fuse or dead PSU, but make sure to check what others have outlined.

That's what I suspect as well.

My fully working Audiolab Amplifier blew one recently for no apparent reason,  small slow blow glass fuse to protect the power supply, opens with a small flat blade. (See photo, directly next to kettle, socket)

Be sure if it is blown to replace with the correct type, there are slow and fast blow, and various amp ratings, will be a code etched into the metal of the fuse.

RE: completed MK 3 S+ Kit No Power

@dan-rogers

Power Panic can be left disconnected and the printer will still work... (Power panic will not work, obviously)  
Sometimes disconnecting power panic can be used to overcome false signals, when the printer is connected to an uninterruptible Power Supply... 

regards Joan