Diagnosis & Coding Power Supply
#1
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'11 E350, '11 E550, '98 M3, '95 E320
Diagnosis & Coding Power Supply
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.
![](https://mbworld.org/forums/attachment.php?attachmentid=429946&stc=1&d=1622041443)
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.
![](https://mbworld.org/forums/attachments/e-class-w212/429951d1622047921-diagnosis-coding-power-supply-img_4690.jpg)
Likely a limited audience, but what is everyone using?
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.
![](https://mbworld.org/forums/attachments/e-class-w212/429951d1622047921-diagnosis-coding-power-supply-img_4690.jpg)
Likely a limited audience, but what is everyone using?
#2
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MY'14 W212 M276 3.5NA @55kMi
awsome
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.
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.
Last edited by CaliBenzDriver; 05-27-2021 at 12:44 PM.