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[protomech]

Good idea.

Some people will submerge computers in oil for cooling .. all but the mechanical components, hard drives and optical drives.

[Burton]

I thought ATF eats practically anything not metal? I know I use it to remove rust and to break bolts loose by mixing it 50:50 with acetone.

Computer heat generation has nothing on a charger with 7kW running through it I would imagine. All that stated I would be willing to try this experiment.

Would you strip the fans out (given they will likely die anyway) and remove the 'tops' on the chargers? Also what do you think to volume of fluid to charger should be?

Need to start looking for an IP67 aluminum case big enough for three of these. And I will have to figure out how I am going to get the connections outside the unit. It would look slick to have the J1772 connector built into it but that is just another point of failure even if you use RTV to seal it.

[protomech]

CPU: 85-150 watts
GPU: 250-350 watts
motherboard, ram, SSD, assorted other: 20-30 watts

http://www.pugetsystems.com/mineral-oil-pc.php

7.5 kW charger @ 92% efficiency: 900 watts

You'd probably want to remove the separate enclosures and fans.

[firepower]

you could use a cheap bilge pump to pump the mineral oil through a small radiator for even more cooling.
A car heater radiator are cheap to buy and good size or motorcycle radiator or oil cooler.

[WindRider]

Proceed with caution.  10kW is a lot power and the worst thing could happen is pretty bad. 

[protomech]

Some other things to consider.

The Meanwell RSP-2000 supplies begin derating (starting at 100%) at 50C, down to 50% at 70C then they switch off.

I knew I should have studied thermodynamics more closely..

Assume we are willing to tolerate a 20C rise in temps (100% performance @ 30C ambient = 86F, 75% power @ 40C ambient = 104F). Further assume convection + radiation losses are 300 watts constant *handwave*.

With these assumptions, we need to absorb 600 Wh at 30C over 1 hour, or 500 Wh at 40C over 1.33 hours.

Wolfram says we'd need around 11 kg = 22 pounds of oil per 100 Wh heat energy absorbed.

With the relatively low derating point, I don't think mineral oil will work as "heat storage" but instead just as a non-conductive way to move heat into a radiator.

[Doctorbass]

Doc! This is awesome!  I love the chargers and the Tesla!!!

Plus that J1772 adapter with the voltage readout is so cool! Did you build that?

Terry

Hi Terry,

Yes i have built it with seperate parts i bought from http://modularevpower.com/

Teh little AC Amp/Voltage display is very usefull and cheap.. i bought it on ebay for about 9$

I decided to maye my own compact J1772 adapter instead of buying one already built.

Just like my quick charger the main goal  was to make everything as compact as possible.

total cost was about 150$.

[Doctorbass]

@doctorbass

Do you need a '13 to test against?

I have a 2013 Model S 11.4, and I'd really like to be able to use L2 J1772 chargers to their full capability, I'm willing to pay for a finished unit if it works as expected.

I live just outside of NYC, I'm willing to make a trip.

Thanks for the offer. i received few other demand for the 2013, but problem is time... i dont have much as i would...

It would be possible with 3 meanwell model RSP-2000-48 in serie. The best would have been 3 unit of 36V adjusted to 38V but Meanwell dont offer any 36V model at the moment.

The total power would be reduced to about 5200W.    The Meanwel rsp 2000 exist in 12, 24 and 48V.

The best way to get the 116v and the max power is using 3 units of 48V trimmed to about 39V each.  These are rated 42A but in the constant current/power  mode these really give 45A. At 45A and 116V you get 5200W. And these wodl be used to about 80%, giving you a safety margin too

If you would use 2 Meanwell of 48V but trimmed to 56V ( their max allowable voltage) you would get 112V at about 42A wich is 4700W max but the battery would only charge to 4V per cell wich is about 80% SOC. but two meanwell is pretty compact too


Each RS-2000 cost about 432$+shipping

Doc

[Doctorbass]

Potentially interested for my 2012 as well.

Concerns:

1. Have you found a way operate the charger with the bike powered off? I remember BSDThw proposing a solution a little while ago.

I did not tried that yet but i remember it required a simple mod by installing a switch that activate the sevcon individually by sending the V= of the battery to power the sevcon and allow it to activate the contactor. ( the contactor is activated  by the sevcon  instead of the BMM i think..

2. Weatherproofing - could this be stored and operated in a Givi side or top case, provided it was ventilated?

Well the total heat that this charger generate is considerable and the airflow would need to be maintained to the actual stock air flow.

3. Noise - could a larger, slower ducted fan still cool the power supplies effectively instead of six small high-RPM fans?

As well ,  as long as the cfm is restected the 3 modules would work really well. plus this cold increase cooling efficiency because the opening area where  the 6 little fan are would increase alot. 

[Doctorbass]

I have been charging all my ebikes  with these Meanwell RSP serie in the last 6 years now and i can say these are really tough!

I have began with the RSP1500 in 2008. This one was the highest power density 6 years ago. I was charging a 24s lipo pack that i divided in two 12s parallel for charging and serie for use because the mnax voltage was 48V ( 56max)

I blew it once when i accidently connected the charger to the battery in 24s serie connection... .. so 100V dc to a 48V dc charger = bad...  BUT i was able to repair it by miself i just repalced a SCR and a resistor for the crowbar circuit. I still have this meanwell rsp 1500 today and it work really well.... meanWELL !!


Then i bought 2 rsp1000 that i connected in serie with a shottky diode on each to protect their open circuit voltage to not go reverse if one of the menawell enable before the other... This solution was perfect for the 24s lipo and it also was 33% more power density than the rsp-1500. The 1500 is exactly twice as big as the rsp1000.

Then i decided to buy these great RSP-2000 wich are 2.5 time more power density than the rsp-1500. The 2000 are the lastest release of the RSP serie.

What i like is that all RSP have:

-The power factor correction to 0.99 ( = increase efficiency and less heat
-These are constant current and constant power  limited and constant voltage adjustable  from 40% to 110%
-Very tough!
-High industrial quality

Doc

[oobflyer]

Terry gave me a deal on a couple of his old Delta-Q chargers - now I can charge at 4 kW!
OK - it's not Elcon or Meanwell... But it's a lot faster than I was charging before....
Thanks Terry!

[Electric Terry]

You're welcome!   Did you get the J1772 adapter with the pigtails from Harlan? Or are you using your old J1772 plug from Zero and splitting the AC output?

[oobflyer]

Haven't received the adapter yet - I used your three-way splitter. The 120V outlets at the Brentwood charging station are all 20A. I plugged two of the chargers into one of the 20A outlets, one into another 20A outlet, and one into the J1772 via the Zero J1172 adapter.

Incidentally - when I actived the Chargepoint charger - I had intended to use both the J1172 and the 120V outlet inside the charger (a little door opens up), but found out that you can't use both simultaneously.  (Maybe everyone else already knew this...)  If you open the door, the J-plug is locked, if you release the J-plug, the little door locks. I even called Chargepoint to ask them - and they sounded a bit surprised that someone would need both. I didn't explain any further - I just got my extension cords out....

[Electric Terry]

Haha Awesome to see this!!!

Yes, you need 2 different charge point cards to use the Level 1 and level 2 at the same time.  Or to use 2 J1772's on the same station. 

Can't wait to see you post about your next trip!  Hopefully with the J1772 adapter from Harlan by then!

[Doctorbass]

Hey guys...

The RSP-2000 have a max current adjust   !!!

witch translate to max power adjustment depending on the AC availlable you have

There is a pot that you can use to adjust the max current output on the rsp-2000 !!

it is located inside the power supply on the top of the vertical PCB. it is called SVR2.

you can buy one external pot of 5k and replace the actual 2kohm for this one with wires and install it on the outside for easy acces.

This will be very usefull for me when some cahrge statin are 208V instead of 240V. i will be able to limit the output current  to not have the AC input to go over 30A.

This was frustrating to not be able to use the level II charge stations that are 208V because these make my charger to draw 36A instead of 30( on the 240V) and the breaker of the 30A limited charge stations trip....

Doc