EndStop, Heat Bed and stepper driver issue in my prusa i3

Hello,

I am building Pruisa I3. all the calibration done. but i am facing below issues to complete the build and start printing

1. End Stops not working. when i move to home position it is hitting to End stops and moving further motor will not stop.
wiring and all fine. if edit the firmware (using Marlin)
// #define ENDSTOPPULLUPS // Comment this out (using // at the start of the line) to disable the endstop pullup resistors like tis
EndStops are working but not allowing the motors to move to any direction. it echoing "End stop hit"

2. When i ON the Heat Bed my power supply SMPS is getting OFF. i am using 450W multi cord power supply. which is used for PC

3. One of the stepper motor Driver mallfuctaning when i turn the adjusment screw motor will work but aftersome time it will not, same cycle repeting.

If i fixed above issues with the help of you people i think i can start test printing.

Thanks in advance for help.

Chandru.

Edited 1 time(s). Last edit at 12/06/2013 06:16AM by gm_chandru.

2) The power supply question is answered in your other thread on the same power supply issue. - your power supply needs to be changed

3) Your stepper driver board or your motor wires may be the problem. Swap drivers and motors around to figure out which it is.

1) Your end stop switches are wired wrong. You need to connect to the other "pole" on the switch.

Thank You Uncle Bob

1. Have changed the wiring and did the changes in Marlin firmware. changed true to false it started working.

// The pullups are needed if you directly connect a mechanical endswitch between the signal and ground pins.
const bool X_ENDSTOPS_INVERTING = true; // set to true to invert the logic of the endstops. -----------------------------!
const bool Y_ENDSTOPS_INVERTING = true; // set to true to invert the logic of the endstops. -----------------------------!
const bool Z_ENDSTOPS_INVERTING = true; // set to true to invert the logic of the endstops. -----------------------------!
//#define DISABLE_MAX_ENDSTOPS

2. Heat Bed, i have cheked my power supply it is 12V and 25 A. 450W lot of people using this as power supply. you are right using Dedicated one is always better.

In the weekend i try to start heat bed by connection another yellow and Black cable which is in other set of cables coming from SMPS after On the Heat Bed. it On and after 1Min Fumes came and SMPS switched off. i checked the heat Bed. back side One line Burnt Out. i dont know this is a manufacturing issue or i did any mistake. ( as per knowlegde i have not done any wrong wiring i have gave + and - correctly and connected 12V 25 A wire Yellow and Black. Have attached the image PFA

3. I have done the swaping before posting here and only that Driver has the problam motors are fine. asked for raplacement and i am getting it.

Thanks,
Chandru.

That heated bed board is fried (litterly). I'd *guess* it's a manufacturing defect. Without tearing the board apart it's tough to be sure.