Powering a Portable Soldering/electronics Station ??? - Page 1
Forum section: electronics / general

author: thekarlmiller@gmail.com
author_rank: Newbie
timestamp: March 16, 2021, 10:03:01 pm
content: I need some help designing or finding or commissioning a multi-faceted switching DC power supply.I would like to integrate several DC powered devices into a single enclosure with the LEAST number of power supply(s) providing power to these devices.Not every device needs to be used simultaneously, but several will be used in conjunction with others (e.g. soldering iron and microscope).I live in the US, so the mains power is 110 Volts with 15 amp breakers.A picture of how I envision this looking is attached.The devices (with mains-connected power supply requirements) are these:(these all have DC switching power supplies)1. 24v / 5a - KSGER T12 Soldering iron & controller2. 24v / 30a - KSGER 858D Hot Air Rework gun3. 12v / 30a - KWeld Spot Welder kit (they say you can use an ATX power supply)4. 12v / 5a - USB charger for 2.0 and 3.0 (with USB-C connection and fast-charging)5. 840 watts - Bench power supply:+ separate fixed voltage 3.3v, 5v, 12v power rails+ one variable voltage and adjustable amperage up to 48v6. 5v / 5a - Microscope / Display7. 5v / 1a - magnifying LED light8. 12v / 1a - Fume Extractor fanThe designed power supply needs to be safe with:A. protection against short circuit at outputB. protection against short circuit at inputC. protection against overheatingD. protection against low and over voltage at the ouputE. protection against reverse polarity inputF. filtering for noise generated by switching power supplyG. connection to earth groundH. protection against over-current (fuses?)Option for battery pack for minimal configuration:* can I use a couple of 20v battery power tool packs as an alternative power pack* could the battery packs be charged when connected to mainsThe reasons why I am considering creating one huge power circuit, is:* small size - this is meant to be portable* minimize enclosure wiring complexity* improve efficiency, but more importantly heat generatedSo, my main questions are:* how do I go about turning all this into a functional and safe design/circuit?* can it be bought as specified for a sub-$200 USD price?* can I pay somebody to design this inexpensively?* what would you do if you wanted to create this?* how could this idea be modified to reduce power supply requirements to avoid creating a 3400 watt power supply?* is there an alternative to designing this for somebody with no formal circuit design education? (I'm a career software guy but I have designed some simple PCBs* is there a better place to ask (not google please))

author: james_s
author_rank: Super Contributor
timestamp: March 16, 2021, 10:09:26 pm
content: The 840W power supply is going to necessitate a massive battery pack if you intend to use it anywhere near full load for a significant period of time.If it were me, I'd probably assemble a battery out of a whole bunch of salvaged 18650 cells or maybe EV cells, there are a number of surplus companies that sell that stuff. I'd also consider just using an inverter to power standard off the shelf 120VAC gear although the 24V stuff will work too. For the modest power stuff I might go with a buck regulator to step down the voltage of say a 36V nominal battery pack. The 840W power supply is going to be the biggest challenge, the other gear won't draw much. Do you really need a power supply that large? My "big" bench supply is around 200W. I have some larger 12V server PSUs when I need a LOT of power and 12 or 24V will do.

author: thekarlmiller@gmail.com
author_rank: Newbie
timestamp: March 17, 2021, 01:57:21 am
content: Thank you for your thoughts. I am thinking you are probably right about the bench power supply requirements. My eyes might be bigger than my belly on that one.As a matter of fact, I don't even own the kweld unit yet, which is only in the design because I want it, and it has the worst electrical problems of any component.My thinking often tends to lean toward pie-in-the-sky as I consider how to solve as many problems as possible.Part of the reason why I was treating this like a product design, is because I thought a fold up electronics bench of sorts would make a great "starting maker" kit, and my two sons would love one.When I consider the value of everything together, being able to build all that into one kit would be great for a bunch of folks just starting out, so I was thinking the power is the most important part to get right.