Mudd Flapp Ranch- PrintNC Cisco WS-CAC Power Supply modification

Modifying the Cisco WS-CAC-2500 to provide 42VDC, 12VDC and 5VDC outputs. This is a very capable switching power supply that is available on the cheap in the used market as the Cisco 6500 server systems approach the end of service.

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[johndiedrichs]

this is golden. Im thinking of also swapping out the noisy fan for something quieter.

[hazzaaalayoubi]

Thank you for this Great video sir. I would like to know if we can do a variable power supply From 3.3V to 50V ? many thanks.

[GaryLordsWayMinistry]

I'm wanting to get 53.5 volts out of mine so I can drive 2-MRF300 AN and 2-MRF300 BN LD mosfet in a push pull configuration. Here's the board I am working with; any help in helping me crank up the voltage out of this unit would be a great help to me.

[kieranblack]

Great video. I am going a similar route and have a couple of questions.

1. On the PrintNC wiki there is a note that some of the 12V and 5V pins voltage drops when current is pulled on these pins or in some cases, the PSU goes in Fault Mode when current is pulled. Is this something you experienced as I noted you pulled a couple of pins of each.


2. What contactor did you end up using in your setup.

Thanks for the informative video.

[hqiu]

Great video sir. Do you have a complete pin out of the back side 29 pin connector? many thanks. Also, would the psu work fine if it runs with no load?

[gizmobowen]

Just for clarification, can you go over what you're using each one of the voltages for? I'm assuming 42 volts for the drivers. Then the 5 volts for the enable pin on the drivers. Finally 12 volts for the BoB and maybe for some relays?
I'm starting to work on the electronics for my system and will just be using the 36 volt supply from Aliexpress that came with the kit. I also have a 24V power supply that I took off my Ender when I replaced it with a Meanwill unit. I know you can get 5 volts through the USB connection to the BoB. I have thought about using a voltage converter to just take a line off the 24V unit and run that to the enable pins on the stepper motor drivers. Seems like one less cable to run to the computer.

[tomaszgillner]

I've cut the plug, got the wires soldered and now trying to work out what causes "output fail" error. Any ideas? Thanks

[plojm]

Can you do current adjustment on the 42v. Is there a pot somewhere that could be used?

[KilSwitch]

Very nice work. Can you please give is the stl file available :) preferably a link on thingiverse.

[johnpeters]

I would prefer not to have to crack open the power supply. You mentioned an output plug / pigtail is available. Would you have a part # for this. Cheers.

[angelic]

Could I use this to run a cheap mig welder?

[grahamstewart]

Useful video for modifying the output connection, but unfortunately the explanation for how this power supply works is entirely wrong. The explanation given is for a linear power supply, but this is a switching power supply and works quite differently. The devices on the heatsinks are mostly switching mosfets and the larger transformers are flyback transformers.

[TheAnthonyBrandi]

So these just turn on. I have a 6000w one and it won't turn on.