New Laser build questions

[mafil25]

ok, so I'm working for a company that uses laser engravers to cut sandpaper. I've just gotten a prototype almost running and I'm having a few issues that I wanted some help with. I'm using the phcad4.38 with corel draw and the corresponding board. I think my boss is ordering a 150w power supply from lightobject as we speak though. basically just wanted some input before I wire in the new one in case I've got something connected wrong.

Hi Shirley,

This is Matt, I'm the tech that is building the machine with the power supply and tube in question. I got everything hooked up and wired in correct and set up a water flow for the laser tube. I just test fired the laser to make sure that it worked properly and it did. then we installed the mirrors. after the mirrors were installed we turned the laser power down to 50% because the power was too high for sighting in the mirrors. I fired the laser many times while setting up the mirrors and it worked flawlessly. I then powered down the machine. I had a few parameters to change with the size of the worktable so I powered up the first part of the machine. I have it set up in stages where the main power turns on the circuit board and chiller/waterpump for the laser. the second switch turns on the stepper drives and makes power available for the laser, but there is also a third switch for the power supply. ok, so I turned on the main power and made the adjustments to my worktable size to compensate for some that the mirror takes up. At this point the machine was set up and ready to do the first actual cutting. when I turned on the power to the laser I heard a loud pop from the power supply. I have 220v going to the power supply. TL is connected from the circuit board, along with a pwm input set at 25k and a ground from the circuit board going to the ground and the water protection is hooked up as well. After the pop when you fire the laser it still comes on, but it barely lights up. almost like it's barely getting any power. after that I removed the power supply and removed the top case. upon inspection I found that two of the chips that sit against the heatsink were broke in half. I have another broken power supply from one our other laser machines that didn't have the same issue as this one when it was broke so I took it apart to see if it used the same componets and it did. The chips in the other power supply that I have on hand were the same number as the ones in yours so I removed the broken chips from this one and installed two of the chips from the power supply I have on hand. after reinstalling the power supply it still has the same issue as before. I'm hoping that there's just something else blown in the power supply that I'm not seeing, maybe if your tech knows what it may be I could change the component out here without having to ship everything off and take so much time. other than that if the two chips were the only thing broken in the power supply and it's repaired now then when the power supply went it may have taken the tube out, but nothing looks out of the ordinary with the tube or any of the wiring.

also had a question about the limit switches and how they're set up. I have the old version of your board and interface as well on another laser machine and the way it's set up I believe with npn proximity switches I didn't build that one. but everytime you turn that machine on it homes in on those limit switches. I actually ordered some npn switches for my new one after figuring that out, but I was wondering can you set it up with pnp switches to do the same thing, because I'm not having any luck getting them to work properly. does it have to have the switches sending a negative signal back first, and then the others are just extra or what? the way it does now when the system resets it doesn't go all the way to the switch at all, just a very short distance. sorry this is so long, just had a lot of questions.