The Renogy 40A DC/DC is bad. I improved it.

FFcossag Review 7 days ago

Description

The DC/DC part is good, but everything around it is bad :( The high 24/7 idle draw combined with the complete lack of settings for the input side, completely squanders what could have been a good product. And the app is an enshittified joke that's actively hostile toward its users, with a VERY toxic EULA.

GOOD NEWS! This is unit is OEM'd by SRNE and I've tested that it works with the SRNE app, which is much less invasive (as of July 2026).

Hi-res teardown images: https://drive.google.com/drive/folders/1yoY_5q1fkl70VXLh408Qrv0fOVuUze7k?usp=sharing

00:00 Intro
00:53 Let's read the Renogy privacy policy!
01:31 App rant
02:10 Idle power consumption
03:50 Broken UVP
04:28 Input voltage range
06:06 Reducing idle draw
08:09 Looking at the PCB
11:32 Power draw demos
15:02 Demo in vehicle

Throw money at me: https://patreon.com/ffcossag
Music, when applicable, supplied by https://combatplayer.bandcamp.com/
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