{"id":1254,"date":"2017-12-10T23:31:37","date_gmt":"2017-12-11T06:31:37","guid":{"rendered":"https:\/\/dubinko.info\/blog\/?p=1254"},"modified":"2017-12-10T23:31:37","modified_gmt":"2017-12-11T06:31:37","slug":"power-supply-build-2","status":"publish","type":"post","link":"https:\/\/dubinko.info\/blog\/2017\/12\/power-supply-build-2\/","title":{"rendered":"Power Supply build: part 2: component selection"},"content":{"rendered":"

In the previous posting<\/a>, I went over requirements for a DIY power supply build. Now on to the fun part–shopping!<\/p>\n

Case<\/h3>\n

I wanted something fairly compact, but still nice looking. I ended up going with Jameco ABS Heavy-Duty Instrument Case<\/a>. It’s a good quality build. In metric, it’s 200mm across, and 64mm tall, which is just about right. I wasn’t looking forward to hand drilling, and worse, cutting rectangular holes in those end-plates though. We’ll come back to that.<\/p>\n

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This case has a really unusual pattern of mounting holes in the bottom surface. I’m sure there’s ready-made circuit boards that would fit that spacing, but I wasn’t planning on wiring this whole thing up at the component level. So we’ll have to stick a pin in this part too, and revisit later.<\/p>\n

AC to DC<\/h3>\n

I originally sought to get a single board that took 120volts AC in, and came with dual, indepenent outputs. Without reading too closely, I picked up from Jameco a Mean Well “dual” output board<\/a>. It looks like it was designed to provide both a DC output, as well as a battery charger output. After it arrived, a bit of inspection showed that the two outputs were not independent at all. Trying to (for example) connect them in series would create a short. So for my purposes, I had a high-quality single-ended supply only.<\/p>\n

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One down, one to go.<\/p>\n

It would have been natural to pick up a second identical Mean Well board. But thinking about the requirements, I saw an opportunity to try out something else. The maximum current on the Mean Well was around 3 amps. Perhaps I could do better, at least on one channel? Who knows when I’ll be trying some crazy electroplating experiment and need it. So after more shopping, I settled on the GEREE AC to DC Converter 85 ~ 265v AC to DC 12V 8A Adapter\/Industrial Module Switching Power<\/span> Supply<\/span><\/a> by way of Amazon. This baby can put out up to 8 amps.<\/p>\n

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Regulators<\/h3>\n

These things come from many different overseas manufactuers, under a variety of names, but they all look like this: 5A Constant Adjustable LED Dual Display Amp\/Volt<\/span><\/a>. They are actually two boards stacked togetehr with conductive risers. The bottom board is a constant current\/constant voltage buck regulator, so it can produce an output anywhere from a bit less than the input, down to a few hundred millivolts. Great. Allegedly, they can handle up to 5 amps. I have my doubts, but we’ll see. (And if I blow one up, it’s easy to replace. Hooray for DIY!)<\/p>\n

\"\"<\/p>\n

The top board is a voltage and current display. I started out with grand ideas of replacing the LED displays with larger seven-segment modules, but that quickly got complicated. At least I got a chance to learn how to lay out circuit boards in KiCAD.<\/p>\n

Voltmeter\/Ammeter<\/h3>\n

OK, spoiler alert. I ended up using separate voltmeter\/ammeter modules, like these:DROK Digital Current Tester Multimeter DC 100V Volt 2A Ampere Battery Monitor Gauge 2in1 Red\/Blue 2-color LED Display Car Automotive 12V 24V Built-in Shunt<\/span><\/a>. So much for the larger LED display. These are only 0.28 inches, but it’ll have to do. And I like that the LEDs are different colors for voltage vs. current.<\/p>\n

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So there’s the major pieces. But there remains the significant job of hooking everything together professionally, safely, and upgradibly (if that’s a word). How things connect together is make-or-break on projects like this. Let’s spend some time going over connectors in the next installment.<\/p>\n","protected":false},"excerpt":{"rendered":"

In the previous posting, I went over requirements for a DIY power supply build. Now on to the fun part–shopping! Case I wanted something fairly compact, but still nice looking. I ended up going with Jameco ABS Heavy-Duty Instrument Case. It’s a good quality build. In metric, it’s 200mm across, and 64mm tall, which is…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1183],"tags":[1172,1212,1200,226,1221,1222,1218],"class_list":["post-1254","post","type-post","status-publish","format-standard","hentry","category-electronics","tag-amazon","tag-component","tag-diy","tag-electronics","tag-jameco","tag-module","tag-powersupply"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t