Safety concerns small 5V power brick - Page 1
Forum section: electronics / beginners

author: MisterD
author_rank: Newbie
timestamp: September 25, 2017, 07:47:35 pm
content: Hello,I would like to power an ESP32 using one of these:https://www.aliexpress.com/item/TSP-05-replace-HLK-PM01-AC-DC-220V-to-5V-mini-power-supply-module-intelligent-household/32705471039.html?spm=2114.search0104.3.17.Zf7HkO&ws_ab_test=searchweb0_0,searchweb201602_3_10152_10065_10151_10068_10344_10342_10343_10340_10341_5470017_10304_10307_10137_10060_10302_10155_10154_10056_10055_10054_10059_5370017_10532_100031_10099_5460020_10338_10339_10103_10102_10052_10053_10142_10107_10050_10051_5380020_10326_10084_10083_10080_10082_10081_10177_10110_10111_10112_10113_10114_143_10312_10313_10314_10078_10079_10073-10051,searchweb201603_23,ppcSwitch_2&btsid=7c555468-0e23-4eae-9839-a32e9ed73606&algo_expid=13fdb94f-2cd5-4c31-8b34-24e4889c78fb-2&algo_pvid=13fdb94f-2cd5-4c31-8b34-24e4889c78fborhttps://www.aliexpress.com/item/Free-Shipping-220V-5V-AC-DC-terisolasi-Rumah-pintar-HLK-PM01-Beralih-step-down-modul-power/32351477609.html?spm=2114.search0104.3.25.Zf7HkO&ws_ab_test=searchweb0_0,searchweb201602_3_10152_10065_10151_10068_10344_10342_10343_10340_10341_5470017_10304_10307_10137_10060_10302_10155_10154_10056_10055_10054_10059_5370017_10532_100031_10099_5460020_10338_10339_10103_10102_10052_10053_10142_10107_10050_10051_5380020_10326_10084_10083_10080_10082_10081_10177_10110_10111_10112_10113_10114_143_10312_10313_10314_10078_10079_10073-10051_10112,searchweb201603_23,ppcSwitch_2&btsid=7c555468-0e23-4eae-9839-a32e9ed73606&algo_expid=13fdb94f-2cd5-4c31-8b34-24e4889c78fb-3&algo_pvid=13fdb94f-2cd5-4c31-8b34-24e4889c78fbAre any of these types of devices safe? I would like to place this in a wall behind a wallswitch, so I'm concerned for firehazards. Looking at the specs it should be ok.Or should I look at other sites to order something like this? (RS components or others?).Other things I should look out for? Ripples on the output?Best regards,Jan

author: rdl
author_rank: Super Contributor
timestamp: September 26, 2017, 01:29:28 pm
content: In the US, and probably elsewhere, you can buy replacement AC outlets with built in USB power ports. That is what I would try to use.http://www.homedepot.com/b/Electrical-Dimmers-Switches-Outlets-Outlets-Receptacles/USB-Port/N-5yc1vZc33aZ1z0r7vs

author: Back2Volts
author_rank: Unknown
timestamp: September 26, 2017, 02:17:35 pm
content: Quote from: rdl on September 26, 2017, 01:29:28 pmI have one 2xoutlet/2xUSB from EATON at hand. Rated 3.1A. It has the back shell held with star screws, so it could be open and possibly put wires to the back. That said I have never seen switch/USB plug combinations. All I have seen are outlets/USB.

author: Back2Volts
author_rank: Unknown
timestamp: September 26, 2017, 02:35:38 pm
content: Quote from: MisterD on September 25, 2017, 07:47:35 pmI find the whole thing very risky... my concern would be the legal/insurance implications if there was a fire.There are ac/dc converters in the same form factor from known brands. A quick MOUSER search shows a MEAN WELL unit around $7. How would you integrate the whole thing? How would you handle the mains connection? How much spare space you have in the electrical box?

author: MisterD
author_rank: Newbie
timestamp: September 27, 2017, 08:34:37 am
content: See attached image. I was thinking of putting the 5v power brick into the wall electrical box and fuse it. The 5v will drive an esp32 board and a relay to switch lighting. Also thinking about putting the relay and power brick into a small 3d printed box separated from the esp32.

author: mbless
author_rank: Regular Contributor
timestamp: September 27, 2017, 10:33:30 am
content: The Hi-link power supplies have been discussed in lengthherewith a good reviewhere.I've tried them out with success, but I also used a MOV, fuse and a thermal fuse to be safe. I also bought them through aliexpress and received counterfeit ones, so I'd buy them through their website instead.Edit: *standard warning about mains electricity killing you if you don't know what you're doing*