In the past, there wasn't much need for a dedicated power supply. Now when running longer diagnostics or coding, the current draw is high enough that'll deplete and lower the battery voltage rather quickly. I'm seeing anywhere from 20-40A when running basic diagnostics. Even higher when running things like Airmatic, blower fan or seat pneumatics.

The Solar PL2320 with a 20A PS mode wasn't cutting it. Wasn't ready to drop $500+ on a dedicated vehicle PS like a Schumacher INC/DSR, IOTA, Clore PL6100, etc... A few google searches later and I was set on building a PS based off an enterprise grade server PSU. These PS builds have a large following in the RC world and to a smaller extent car programming. Their very well made and were cheap (<$30) due to surplus.



The first one I tested blew the input resistor within the first day of building/testing it. The second has lasted 4 months (maybe 15-20 uses) and gave up the ghost. When the first one blew, the seller noted that these are 10+ year old units, used 24/7 in server and replaced on a schedule. Granted I modified to increase voltage and over-voltage protection like many others do. Other's have had better experience and I would have gave it a third go... but now the prices are $70+ each. More info these: https://mbworld.org/forums/e-class-w...onitoring.html

Searched for replacement, found these:

https://powermaxconverters.com/product/pm3-12v-series
https://cbradiospronto.com/product/p...d-power-supply
http://www.megawattpowersupplies.com/

Both referenced in HAM community forums and to a lesser extent some car enthusiast. The former being a battery charger/PSU marketed toward the RV crowd (charging house batteries/bank) and made in China. The latter a PSU marketed toward the HAM community, US-made, modular, higher cost.

Ordered the PowerMax PM3-100 (100A) off Amazon and have decided to give it a go... this way if I'm unhappy I can easily return with Prime. The output is adjustable from 13-16 VDC.



Likely a limited audience, but what is everyone using?

 

this 100A unit is awsome 🤗

When working on your personal cars... I'd charge up the battery to limit the in-rush spike when you connect your 100Amp source set not too high around 12.5...12.7 V for the same reasons -

Nearly unlimited current means it really is the opposite of a charger with transition ramps 😃

If you are interested in doing a little manufacturing QA in your PS unit...:
Check the heatsink temperature sensors (diode junction) have proper thermal contacts to sense the output stage temp.

Also take a close look to solders quality on the power path.