Motherboard DC Jack broken

Those are motor drives for high efficiency blower motors in the picture. I work in the R&D division of HVACR at nidec motor corporation. Those drives were getting the smoke let out of them for UL testing.

Got it, variable frequency drives are quit common nowadays. I recall a state of the art (at the time 1991) that used VFD on the hugh air handlers. Fist I had ever saw I read about them and they were the reason for me to get involved in building automation, energy management systems and controls systems. If I could have not injured my back in 2005 I would be raking in some dough.
I was quite good at controls at that time and attended many, many schools, workshops, seminars etc. to obtain my knowledge.
I suppose they are as much common place today as lighting. I was in big demand and Headhunters from all over the world were contacting me trying to get me to work for company x, y or z. I have been all over USA for training but mostly New England, Illinois, and a few other places. At this time I can’t remember what I was doing 20 minutes ago so most is gone from my memory.

Once I was scheduled for. 2 week school in Greater Boston. So as time approached I was prepared to go and it was the Friday after the 9-11 attack when my flight to Boston was scheduled. When I got to the Airport in Memphis TN, It looked like a war zone it had National Guard troops arm and loaded for bear. People were very weary of each other and going through body searches was no fun.
Got aboard and each person on board was looking around and scared they though some of us were maybe terriost. Tention was very high amount what few people were aboard
No way that trip made the carrier any money there weren’t 15 people aboard.

Anyway we flew right over Manhattan in route to Boston you could see the smoke from the now destroyed WTC’s. It was a very trying experience and I felt really sad and depressed since seeing it first hand made me very emotional.

I thought Memphis was bad but Logan was a nightmare military everywhere you looked dogs sniffing my butt as I walked towards the rental car place.

Sorry for posting this on this forum that just brought back memories of that terrible, terrible day in our country. Logan airport was 50 times worse than Memphis as that is where all of the planes departed from. It took 3 hours to get checked onto the plane two weeks later.
Sure glad no one said BOO! Are I probably would not be here to tell this.

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These are actually much more complex than VFDs. They’re more akin to a brushless DC motor but with AC as your input. They can control voltage, current, and frequency.

You are correct, Are they permanent magnet AC ? Back in the day all they did was control the freq allowed to go to the motors. Most in HVAC building applications were controlled by static pressure sensors located in the duct work.
If not for those the air handlers would run full blast at all times. Beside being a means of energy management they would blow Variable Air Volume units out of the ceilings.
As each individual VAV was satisfied by the set point in the room they would throttle down to 10-15% as per ASHRA specs and requirements for proper air flow to remove contaminated air from each zone as each VAV was throttling down and trying to stop the flow of cold or hot air the AHU would slow down as well via the static pressure controls reading high static pressure.
Technology has really changed since I was involved I was in big demand back then now they wouldn’t even throw rocks at me, too much effort for no results.

They are permanent magnet.

We have a torque to cfm mode that can be used to demand a specific cfm for a given input. No sensors required so long as the blower is correct for the motors HP output. We account for the input current via a shunt and RPM is known from 0 passing on the phases. The control can be pre programmed with a list of desired CFM targets and it’s off to the races. There’s a direct relationship of torque to static pressure and therefore volume since the blower area is known.

There’s also 0-10v/4-20ma input and potential for modbus.

Cool, Sounds like y’all got it down pat. Only potential problem is some gooder header tech changes a pulley trying to increase or decrease air flow. How do the Balancing Enigneers balance the air flow? I suppose that is done at each VAV or coil box like in the older days.
But that is 10 times better than the VFD and like you said very complex.

Can you reverse the motor and generated voltage and current like a DC PM motor?
If so accidentally ship me one back when you send the MB back if you get it fixed.
What some fun I could have if I could figure out a way to control the voltage and amps to generated AC power.
I guess it will require cleaning up prior to using it on anything other motors and maybe incandescent lighting .
Then again @60 Hz it made could power a driver for LED. That’s sharp man.

Here are the pics of batt and MB. The dc Jack belongs at the end of the ink pen. I will shoot a pic over Tue of bottom side view After I return from Dr. Appointment.
As you can see it’s not much room to play, hope you can desolder what’s left of the Jack and possibly solder the Jack wires in. It’s gonna be tuff no doubt but nothing ventured nothing gained.

The batt is a Li-po I tried to take pics but could not prop up enough to get steady the MB I had the iPad propped up so it took pretty good after 6-8 tries.

Looks fairly simple to solder to, but do you know what orientation the connector was in?

That I do not know nor can I find out. I have been searching for a replacement Jack to simplify (hopefully) your task. I have tried to locate the orientation on the web but so much junk in the way of actual information.

I don’t know if it’s backwards compatible or what, totally blind.
I was thinking ( there’s that word again) that a 50-50 chance by going with the order on the Jack cable end/plug it will either be left to right or visa versa .

I will continue to search for it but in hopes a dell repair tech may chime in and enlighten me. Then again most techs nowadays just replace the board no board level troubleshooting anymore.

I used to could board level trouble shoot and repair on boards of yesteryear but the digital electronic age and throwaway society stoped that. But a $300 wholesale price on a Trane unit main board would/could justify a board level repair, even the cheaper $150 secondary boards would after a mark up is added.

Today’s technology vs yesterday’s is like a foot surgeon attempting brain surgery, it’s just not the same.
I will continue to try to find the position, I was just on Dell site trying to find something pertaining to it but no one knows anything but just plug the cord into the Jack on the board.

If you’ve got a continuity tester you can put one probe on exposed copper around a screwhole to find ground.

Dell jacks like that have 3 connections, hot, ground and the sense line.

on the board Usually 3 hot, 3 ground, 1 for sense and one not connected.
If you can get the board on I think the sense line is looking for 3v from the charger… there’s probably some protocol for some sort of data exchange so the laptop can verify it’s a dell approved charger so it’ll charge the battery,
. I don’t have a scope to verify that, it may just look for 3v or some specific resistance, but im pretty sure I remember the last time I was poking at one of those with a meter the sense was 3v.

if you don’t connect the sense line, the laptop will run but refuse to charge the battery.

Once you got the grounds, you could probably sort out the 19v input from the sense line by comparing resistance to ground?

I think the sense line may actually be in between the power and ground on the board for isolation.

There are 3 contacts on the back of the jack…not entirely sure why they use 3 individual wires blobbed together for the power and ground… Maybe fault tolerance or to prevent the wires from overheating during high draw?

Also, looking at the pic there’s a triangle marking pin one on the right side…

probably the 3 hot (red) then the middle two are nc and sense, far left three ground (unless I’ve got it reversed)

Thanks D0rk, I do believe you are correct. The grn wires should show continuity between a ground source on the board and the ground pin sets on the board.
I believe the center wire will be the sense wire and as you stated it will sense a Dell or off brand power supply and not charge the batt although the computer will function, just not charge the batt.
My thinking for the need of three pos and neg wires are the same as yours. Dell paralleled them to carry current in load situations eliminating the need for a larger bulked set of wires. Saving precious space in a confined area.
Through process of elimination I hope to determine which is which prior to shipping the board to my new friend.
Hopefully I can determine what the orientation is so he won’t have to waste his valuable time doing so.
Barring some unforeseen circumstance I plan to pull the board tomorrow and start the process as I had no luck in finding the sequence that the wires should go.
He will have to determine for 100% certain the actual sense wire after he can apply voltage as I have no means other than jury rigging a source of power.

Wait! After process of elimination locating the grn wire and using continuity between the center pin on the Jack barrel and the board side Jack plug will determine the pos, also the outer grn side of the barrel Jack will determine the grn , then grn to grn and all should be good to go.
That make any sense?
I think it can be determined which is which just as you stated, you must have been reading my mind. Thanks so much for your reply and input you verified my thoughts on how to tackle this PITA.

hot 3 left, cold 3 right, sense 4th from right.

Thanks ndesigh, I apologize for not replying sooner. We had a family emergency yesterday and did not get much chance to do much.
Our 5 year old Grandson had to be rushed to Labohner Children’s Hospital in Memphis from Tupelo Hospital for what was finally determined to Be appendicitis.
He just left from Labohner last week from intestines/bowel problems for 4 months and after 5 days they hopefully have his problem solved, he now has to have therapy to teach him to learn to have BM’s.

Little fella has been through a lot since right after Thanksgiving of 2020.
He is scheduled for surgery Wednesday A.M. and we have been left to care for our 2 month old Granddaughter, plus our oldest Daughter had a auto accident but fortunately she is ok.
So things have been rather hectic here.

I did get the MB out of the laptop around 2:30 A.M. but haven’t had the opportunity to check it out or send a pic of the bottom side.
But sounds like that won’t be necessary, so kudos to you ndesign. Thanks so much.
I have Kidney dialysis again today so it will be late afternoon before I can re-located the whereabouts of the Jack cords so things are moving slow on my end.

Thanks so much to all!