• Bosch Indego Battery Pack Connectors

    10/03/2022 at 13:23 0 comments

    From an earlier project, I've got an unreasonable amount of a particular type of 9s2p 18650 Li-ion battery packs. The cells are nothing to write home about, but overall, that nets me about 1.9 kWh of capacity if I can assemble those 20 packs into one battery unit (and probably add balancing, which Bosch didn't seem fit to integrate).

    Connector Candidates

    Some detective work later, here is what probably matches the battery pack connector. The order code seems to be

    • DJ7 / HD (series / manufacturer part)
    • 03 (number of positions)
    • 19, 2A, 22 (series?)
    • -
    • 6.3 (blade width in mm, hence Sumitomo "250 type" (mils))
    • -
    • 1, 2 (male, female type)
    • 0, 1 (unknown option)
    • [-] (optional part)
    • [B] (black plastic)
    • J (unkown option)

    female terminal type
    male terminal type
    "DJ series"

    Haidie #
    ? (see HD0322-6.3)
    Haidie Mfr. #
    ? (see HD0322-6.3)926097-1
    DJ623-E 6,3 B
    Sumitomo 1500-0068 ?
    DJ612-6,3 B
    Sumitomo 1500-0083 ?

    Purchase options:

    "Yueqing Enzhe electric appliance Store" (100 pc qty)


    "AutoAcessories Store" (contact seller for this type and 20-100 pc qty)


    "Haidie Electric" (HD0319-6.3-11J, HD0322-6.3-11J, HD0322-6.3-21J)


    RuiAn Huzhong Auto Electeonic Co.,Ltd. - www.hz-ae.com

    "dojioxcn Co., Ltd. Store" (DJ623-E 6,3 A/DJ612-6,3 B)


    Many Wrong (But Better?) Choices

    I'm not a fan of the 3 little barbs with which the housings lock onto each other, as this promises to be yet more wrestling to mate / un-mate. There seem to exist a wide variety of locking features and pin orientations / positions within a shared plug contour. Most likely the Terminals are interchangeable, but even here variants exist.

    It's often hard to see in the iso perspective pictures, but those orientation variants can really get you. The locking features are perhaps a better corroborating indictor which one is appropriate when matching this style of connector. Here's DJ7032A (left) vs DJ7031 (right):

    Dump: More Information On Similar Connectors

    DJ7031 (latch like DJ7032A, but the contact arrangement is incompatible)

    female terminal type
    male terminal type
    DJ series
    TerminalsDJ621-B 6,3DJ611-6.3B



    DJ70322 (perhaps another match. Confusing!)

    female terminal type
    male terminal type
    "DJ series"
    Haidie #
    Haidie Mfr. #


    female terminal type
    male terminal type
    DJ series

    Sumitomo #



    female terminal type
    male terminal type

    6110-4533, 6020-32616120-2033


    female terminal type
    male terminal type
    DJ series


    If you're still reading: good luck finding your connector. I don't envy you.

  • Normalkonserve 900ccm

    06/20/2022 at 09:39 0 comments

    WWII Era Rations

    Recently, a WWII era preserving bottle ("Einkochflasche") came into my collection. It's not that I'm an avid collector, but it piqued my curiosity, and with 900 mL volume, it seems to be a pretty usable size. Weighing in at 519 g without lid,  the container is rather thick-walled and heavy, which feels nice. The texture is reminiscent of a lime fruit and the bottom stamping is pretty rough, while the inside is smooth. These days, such containers are produced in a two-step process starting from a pressed glass preform which is then blow-molded to its final volume. I imagine that not much has changed in the production process since then, but it does make you wonder whether they had issues with the mold insert. During the war, they might also have preferred to conserve energy and not reject a batch of bottles for cosmetic defects.

    Here are a few shots from the top and bottom features:

    There are some rusty, calcified crusts on the neck. The neck has a groove but no threading. With an ID of 56-57 mm and an OD of about 66 mm, it looks quite a lot like the 60 RR Weck lids should fit:

    The whole container set also includes a metal spring or clip ("Einkochbügel") and a rubber ring. The rust pattern, especially on the sealing face on the top makes me wonder whether that is historically accurate in this case. With ordinary tolerances for pressed parts, One might also question whether < 1 mm is enough tolerance to begin with. Other WECK containers have a rather loose fit even today with better machinery and process control. Matching lids would have to have e.g. 54 mm diameter to fit into the nominally 56 mm bore.

    As chance would have it, an auction titled "Normal-Konserve-900-ml-Bodenfund-Wehrmacht-verschlossen" (only cached preview available, auction has since vanished) depicts what looks like a crimped metal lid used in conjunction with this type of bottle:

    On the other hand, contemporary specimens from another auction do show, in this case an INKO brand, a glass lid and metal clip (which may have been used for the cooking step only):

    ps.: I found a cheap set of WECK RR 60 lids, and indeed they fit just fine.

    Good Things Come In Reusable Packages

    To give some context: in Germany alone, over 4 million tons of glass containers were produced in 2020. At the same time, bulk food stores targeting environmentally conscious customers were struggling or went out of business during the Covid-19 pandemic. I personally have reservations when it comes to the hygiene aspect of open bulk food and self-service, yet I find that there is a need to explore reusable food containers in the same way it works for beverages.

    As it stands, there are only a few brands (like Ehrmann, which are however criticized for other practices), that field reusable food containers (basically like the container shown below on the right), yet there are non-returnable, reusable food containers in the market as well. As an example, let's wrap up the glass situation with the coconut oil jar on the left:

    Can We Have Nice Things?

    There are many shelf-stable products offered today which come in single use glass containers, and that makes me wonder: why isn't there a standard container for spices, a standard container for pickled foods, or more valuable dry goods like nuts, seeds, lentils, beans, dried berries? Larger containers could be a bit more blocky and pack well in euro containers for easy and space-efficient transportation and storage.

    An overarching technical topic might be making good lids. The glass sealing surfaces can be automatically inspected before refilling, but lids will likely still need to be disposable, or at least the sealing inserts / foils will need to be.

    One can even imagine standardizing food containers for bulk food stores that offer pre-weighed quantities in returnable glass containers with lids that have labels on the lid that reset...

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  • Intel D410PT mainboard won't turn on anymore

    05/04/2022 at 23:58 2 comments

    I bought a device that harbors a Mini ITX mainboard (Intel D410PT(B)). It also had a power supply failure, so we're left wondering whether that in turn damaged the mainboard as well. First off, this is a no-fix, but maybe you'll enjoy the story of the journey.

    Initial presentation:

    ATX power supply is completely dead.

    It's a Seventeam ST-250UAG-05E, a regular 1U server PSU. When connecting to mains and bridging PS_ON# to GND, it should turn on, but no 5V_STB is present either.

    It's got active PFC creating a 380V intermediate DC rail, so there are > 400V transients across its 20N60 MOSFET to be expected (capacitor ESL and commutation loop causes some overshoot. Can you see it?

    Here's a closer shot:

    It should be noted that in the pictures above, the worst of the contamination (paper and toner dust, as this was an office scanner) has already been vacuumed out and brushed off while vacuuming. The charred remains and light metal deposition over the "R17" silkscreen label, along with the fancy golden alloy that formed around the arced spot tells what happened here. The clearance between those two traces really is overly optimistic and inadequate for adherent pollution.

    As per https://www.protoexpress.com/blog/importance-pcb-line-spacing-creepage-clearance/ , IEC60947-1

    Pollution degree 2 would apply: "Mostly, there is non-conductive pollution. However, there is a possibility of temporary conductive pollution, which is caused due to the condensation. Laboratory area is one of the examples of pollution degree 2."

    Let's see what 400V working voltage and pollution degree 2 call for:

    What's that you say, 2.0 - 4.0 mm, not 0.8mm? Admittedly, there's not much room when one has to work with TO-220. But there are two ways to avoid arcing as a failure mode:

    1) staggered pins can directly increase clearance, albeit at increased assembly effort
    2) isolation slots added to the PCB improve creepage distances, while potentially increasing PCB cost. Dust may still accumulate in the slot, as the power supply is forced-air cooled.

    3) the best result is achieved by combining staggered pinout and isolation slot milling.

    The PSU needs to be fixed.

    It ain't fixin' itself. OK, that's not completely true, maybe the ablation caused by the arcing did fix it somewhat, but upon measurement it turns out that the MOSFET is OK, but the 5A fuse is blown.

    Course Of Action:

    • clean and abrade arc damaged on PCB (heat-affected PCB material can become a future source of arcing and recurring failure)
    • trim traces with exacto knife
    • reflow with some flux
    • thorough cleaning with ethanol or mineral spirits to strip flux residues
    • application of Plastik 70 conformal coating (acrylic resin)
    • test*

    This restored the PSU and allowed the machine to be powered when adding a wire to short PS_ON# to GND. The mainboard however would not start at this point when merely shorting the PWR button pins on FP_HDR.

    (*) Earlier I mentioned 380V for the PFC stage. As one doesn't get proper technical documentation these days, this voltage was measured after fixing the PCB and fuse. I've got a 250V lab power supply set to a 50 or 100 mA limit to keep the risk of electric shock and device damage limited. it also allows gradually ramping up the input voltage under a current limit. Most switch-mode power supplies also run off DC without issues, and start at 85 - 100V AC with universal input, so they should accept 150-250V DC as well. 100 mA aren't particularly safe and the floating output means there is no RCD saving the day - maybe a future lab upgrade might be a dead man switch that cuts the interlock after 10 seconds without a button press?

    Further reading: https://www.powersystemsdesign.com/articles/safety-vs-performance/36/10909

    The State Of The Mainboard

    It has a green power indicator LED which lights when the now-fixed PSU is switched on, 5V_STB is 5.1V.

    As it turned out, the mainboard wouldn't just start the power supply when cold-started, but started...

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