Standardizing DB37 connector pinout for up to 32s

[NeilP]

http://www.winfordeng.com/products/brk37.php

I just finished making up a break out board on a piece of vero board..damn

[Bison_69]

Hi Guys,

I think it is kind of odd that you are looking for such a cheap connector as the “D-Sub” type… which is not rated at all for outdoors used nor for harsh environment.

Mostly for the huge investment ($$$$.$$) you made so far to build and convert your ebike… it is somehow hard to understand why to invest on such a cheap component to risk the loss of your battery pack while there are so many better choice out there on the market. (I don’t mind to pay a little more for a connector kit which I can rely on long term and keep my mind in peace)

Here is a very good source to look at for technical info…
http://www.ept.ca/pressroom/

Still for those which only believe in the D-Sub type connectors… I enclosed is a technical specs pdf to better help you and understand that those connector are really not offering much beside indoors small signals and computer used which they were engineered for in first place.

SG

[jonescg]

Well I wouldn't be putting my D-subs out in the breeze for crap to collect anyways. They are going under a sealed, waterproof cover and will have their own rubber condoms to protect them from any stray dust. The idea will be to have a pack that's so well balanced you don't even need to access them more often than once a month or so.

However, despite their 2-5 amp ratings (which is pretty good I would have thought) they aren't really rated for repeated plugging and unplugging. 500 insertions I read on that data sheet? Now, from a LiPo perspective, 500 cycles is a good lifespan! So I really don't think the d-sub will be the limiting factor here. But a touch up with graphite powder and a good blast of compressed air would make them process much smoother.

[amberwolf]

Just be careful with the graphite powder, so you don't wind up with conductive paths for leakage currents between cells. Very important at the voltages you're going to be at, especially.

A little humidity and the graphite and maybe other contaminants could mix and make interesting compounds that would probably be conductive enough to cause problems.

[Bison_69]

The ever best made all purpose dielectric grease is made by DOW CORNING which I have been using for the last 25 years....
(We were using it a lot during my military service)

http://www.dowcorning.com/applications/search/default.aspx?R=402EN
It prevent oxydation on electrical contacts, lubricate and also keeps rubber boots in good health (avoiding them to dry)

This stuff is pretty amazing.

SG

[Doctorbass]

13 april 2012 Upgraded desing on first page.

Thanks Camlight and Bigmoose for the advice.

I did not wnat to be too far from a config with pin number corresponding to cells for easy understanding... but safety and longevity is the best so this way the connector pins will have minimal voltage from each adjacent pins

Doc

[bigmoose]

Doc, I like your new layout. Looks good!

I am heading towards an AMP CPC Plastic connector with near Mil spec Pins. The cheap pins are good for 13 amps at about $0.75 a pin pair; and if things get dicey there are 17 amp rated pins at about $2.40 a pin pair in Series 1 size 17-16 pins will do 12 cells; but for 48 volts I have to go with Series 1, Size 23-37 pins. That size 23-37 connector is like 1.75 inches in diameter though!

[Doctorbass]

Doc, I like your new layout. Looks good!

I am heading towards an AMP CPC Plastic connector with near Mil spec Pins. The cheap pins are good for 13 amps at about $0.75 a pin pair; and if things get dicey there are 17 amp rated pins at about $2.40 a pin pair in Series 1 size 17-16 pins will do 12 cells; but for 48 volts I have to go with Series 1, Size 23-37 pins. That size 23-37 connector is like 1.75 inches in diameter though!

I already used these Amphenol connectors. They are excellent!.. but a bit pricey compare to the DB

Do you know why i like the DB connector?

D... B........ Doctor Bass Connector

Doc

[caspo6]

I have a 24s2p pack of LiPo 5aH bricks with Methods parallel boards and x2 Hyperion 1401 balance chargers on their own power supplies.

I want to be able to balance charge with a single DB37 connection to my pack.

I was thinking of creating a balance board with the layout and pinout below. I would solder a 12 gauge wire to the wide traces and use Anderson power poles to the battery chargers. Any thoughts?? Am I missing something? Is it okay to balance the two 12s groups using the common lead between them to the two chargers? Are 0.3 mm trace gaps and 0.54 wide traces adequate on a 1 oz board?

DB37 24S JST-XH BALANCE BOARD.JPG (89.48 KiB) Viewed 103 times

DB37 24S JST-XH BALANCE BOARD PINOUT.JPG (77.71 KiB) Viewed 103 times

[Toorbough ULL-Zeveigh]

Do you know why i like the DB connector?

D... B........ Doctor Bass Connector Doc

Cannon's part-numbering system uses D as the prefix for the whole series, followed by one of A, B, C, D, or E denoting the shell size, followed by the number of pins or sockets, followed by either P (plug) or S (socket) denoting the gender of the part. Each shell size usually (see below for exceptions) corresponds to a certain number of pins or sockets: A with 15, B with 25, C with 37, D with 50, and E with 9

[jonescg]

Holy thread revival batman!

I don't have much to add except that I've come around to the non-sequential pinout being advocated. Mostly as a result of soldering a live pack into the back of a DB25. I followed something similar to Doc's first image. No sparks whatsoever because I shrunk down each lead after soldering it

Now for my race bike I will be using four of these D-sub 44 HD plugs:



Unfortunately there is only just enough pins for my 43 balance wires. I believe 28 gauge wire will suffice for monitoring or balance charging at an amp or so.

[Toorbough ULL-Zeveigh]

Now for my race bike I will be using four of these D-sub 44 HD plugs:
Unfortunately there is only just enough pins for my 43 balance wires. I believe 28 gauge wire will suffice for monitoring or balance charging at an amp or so.

if you need a few more lines then DD50 might be the way to go.
takes up less length anyways than DC37 while retaining regular spacing & full sized pins.
or did you happen to miss this caveat from page1?

I already used the DB44 connector for a 40s BMS but.. the pins are too fragile and too close!

[jonescg]

Yep, I did miss that one

I didn't realise the 44s used smaller pins / solder buckets. In that case the double D ( )50 might be ideal.

[johnrobholmes]

..... Is it okay to balance the two 12s groups using the common lead between them to the two chargers?

Split the common lead into two paths, this way you do not need multiple isolated charger power supplies.

[Doctorbass]

Do you know why i like the DB connector?

D... B........ Doctor Bass Connector Doc

Cannon's part-numbering system uses D as the prefix for the whole series, followed by one of A, B, C, D, or E denoting the shell size, followed by the number of pins or sockets, followed by either P (plug) or S (socket) denoting the gender of the part. Each shell size usually (see below for exceptions) corresponds to a certain number of pins or sockets: A with 15, B with 25, C with 37, D with 50, and E with 9

Oh you are right !