Question for ManuelW

[racerr73]

Hi Manuel,

I noticed in your HPR06 Cat you have for sale that you have a 24-150 schulze esc in it with modified water cooling and it says 200amp in pen on the esc in one of the pics. Just wondering if you or schulze did the mod, what the mod consisted of, and if the mod has now made this esc from a 150 amp to a now 200amp esc.

Hope you can help us out with some info.

Thanks
Trev

[RaceMechaniX]

Trev,

I can probably answer the question, the 24.150wk is rated at 150A continous and 200A in short bursts.

TG

[racerr73]

Hi Tyler,

Thanks for your reply.

I guess what i was asking is if the modification that Manuel has done will get us more towards 200amp continuous current.

A few members of here in Brisbane, Australia has these speed controllers and are a bit disappointed with them as on set ups which we thought should be fine for it to handle, it simply doesn't, 3rd lap in and they thermal and stop. I know these only have the 1 water tube down the side of the board which i believe is the problem with them, they aren't getting cooled enough which is why i am interested in the manuel mod.

Set ups i am talking about are 8xl or even 1515/1y neu on a 440/3 prop won;t get home for a 5 lap race. However this set up and big props on these motors get home easily on a barra 125 or even a schulze 40-160. Thats only 10amps continuous current more for the 40-160 but the advantage of 2 cooling tubes beisde the board on these controllers, gee even a barra 125 will make it home comfortable. Some of us are using a 40 x 40mm cooling fan on the fets of the 24-150 and this has helped a bit. If you know any other ideas to try and get these esc cooling to work better and at least let us run them on some of our set ups instead of sitting in cupboards it would be greatly appreciated.

Thanks
Trev

[RaceMechaniX]

Trev,

I have run your exact setup in a PT Stealth for P Sport Hydro. A 1515 1Y, 24.150wk, 4S2P and a cupped up 440/3. Likewise I found if the water was warm that the esc thermalled. I ended up running a 32.200wk which had no problem. Honestly the 24.150wk is overrated on current and the 40.160 is underrated. Cooling is the issue as is the 4 fewer FETS per leg. The 24.150wk does not have the second solder pad like the larger ones due to adding a second brass tube will not work. You can add two cooling plates one on the top and one of the bottom to help remove heat from the FETS. This works quite well. Find two cooling plates and use some thermal paste to create a decent heat flux path. Use some Kapton tape or shrink to hold the plates in place.

A little background: A FETs current is rated on what temperature it operates at. Higher temperatures result in current derating and many companies rate the current of their controllers based on optimum cooling which few if any have. So if an individual FET is rated at 75A at room temp, it will reduce to 20A or less at 100C. The 40.160 and 32.200 are reasonably rated given the 10 FETs per leg, where as the 24.150 with 6 FETS per leg is a little overrated when operating at temp.

It should also be noted that FETS come in different voltage ranges and a FET of the same footprint with a lower voltage will typically have a higher current rating. There are other factors as well whcih I will omit.

[racerr73]

Hi Tyler,

Thanks for the extra info about this esc, i will put some cooling plates on it and see how it goes.

Thanks
Trev

[ManuelW]

Hello Trev,

yes the ESC's got a little upgrade with a full 2nd cooling tube on the opposite side as well as two additional cooling plates on both sides covering the FETs. Its not the nicest mod out there but definitely works very well.

regards,
Manuel

[RaceMechaniX]

Manuel,

How did you get the second tube on there?

TG

[ManuelW]

Hi,

well it was not made by me, I bought the boat as it is. Did also take some pictures which I attached below, sadly their quality isn't good. But its not too difficult to explain. First both of the two additional cooling plates are simply soldered to that brass tube. Could be done nicer than on these but it works. Between the cooling plates and the FETs is some heat transfer silicone. You probably not that stuff, its exactly the same as what Schulze used on their old 40.160's to fix the Caps together:



And between the tube and the PCB is some special heat transfer pad (double sided self adhesive). If I would to it I would use special heat transfer glue. Some of the best stuff out there is this:

http://www.arcticsilver.com/arctic_silver_thermal_adhesive.htm

For example from the old Schulze 40.160's or the 32.170's there was a version without water cooling. They had the PCB prepared but no tubes on these. Was very critical to solder them, also Schulze refused to do so. So quite a few were modified afterwards with that stuff, almost as good as soldering.

regards,
Manuel

EDIT: Tyler you got an eMail!

IMAG0550.jpgIMAG0555.jpgIMAG0557.jpgIMAG0560.jpg

[RaceMechaniX]

Thanks Manuel,

TG