More power (literally) for the HP-41, follow-up.

[Massimo Gnerucci]

(06-30-2023 06:14 PM)Sylvain Cote Wrote:  

(06-30-2023 02:36 PM)Massimo Gnerucci Wrote:  In queue since 2023-05-21...

Nah! different thread, does not count.

PRRRRRRRRRRRRRRRRRR!

[Diego Diaz]

Hi again,

Regarding the safety concerns about Lipo battery storage and, though (as Bob has already noted) this would be an uncommon situation in the 'regular' use these battery packs are intended for; it is highly advisable to keep non used batteries (these and any others) into a safe bag.

Search for "Lipo Guard" and you'll get a number of options, formats and sizes. They're cheap (under US$10 for a standard 23x18cm bag) and prevent any damage to the surroundings in case of catastrophic battery failure.

About the current list of beta testers, the first eight names (which include many of the 'usual suspects' :-) in no particular order: Massimo, Ángel, Bob, Sylvain, Matthias, Meindert, Didier and "dmh".

Please let me know in case any you prefer to wait until the final release.

@Sylvain, Regarding the "MORPH" module, I haven't found it in my email archive either. Maybe I think of sending the file but it never happens. Will look for the document as I get back to Spain since it must be in my desktop PC, and let you know.

Best wishes.

Diego.

[JurgenRo]

Great! I'm in for 2 pieces!

[Diego Diaz]

Hi everyone!

The parts from Mouser arrived last week, and prototype PCBs were delivered on Monday afternoon.

So I had a busy Tuesday :-)

All parts fit quite tight in the battery well, and a few dimensional corrections will need to be made for the production version but, in general, the prototype matches the requirements.

However, the "BAT" circuit needs some adjustments. Currently it shows the "BAT" annunciator too early (with more than 50% remaining) but I'm confident this can be sorted out.

Once these checks are completed and if no other problem rises up, I'll be building the remaining 8 units for beta testing along the next couple of weeks.

Attached some pictures of the prototype with battery board detached and then assembled; also how it looks when installed on the HP-41.

All the best from the Caribbean. ;-)

Diego.
   
   
   

[Massimo Gnerucci]

Perfect, I'll be on holiday the next two weeks.

Thanks for the update.

[HP-Collection]

(06-29-2023 12:40 PM)HP-Collection Wrote:  PS: What about your "new" module we heared about las Allschwil Meeting?

What! Where! a new module from Diego ? ... or are you talking about the MAXX module from Monte?

edit: since everybody is putting reservation number, I will take a minimum of 4 units when available.
[/quote]

Sooooooory, mixed it up, it was the MAXX module.

[Sylvain Cote]

(07-13-2023 07:00 AM)HP-Collection Wrote:  

(06-29-2023 02:42 PM)Sylvain Cote Wrote:  

(06-29-2023 12:40 PM)HP-Collection Wrote:  PS: What about your "new" module we heared about las Allschwil Meeting?

What! Where! a new module from Diego ? ... or are you talking about the MAXX module from Monte?

Sooooooory, mixed it up, it was the MAXX module.

You have a PM.

[Johnboy]

Love your wok Diego !

I'll be lining up for a few when they're available.

Cheers,
John
(Australia)

[Diego Diaz]

Hi all,

Thanks for your kind words John.

A couple of the Beta prototypes already built, and time to check functionality and parameters consistency.

Some preliminary specs after these first tests.

Quiescent current drain:
Nominal, battery @3.7v : 440uA
Maximum, battery @4.2v : 470uA
"BAT" ON, battery @3.3v : 330uA

100% charge time from "BAT" ON: 4h 45min (approx)*
80% charge time from "BAT" ON: 3h (approx)*
* May depend on the type of charger used; I'll leave this for the Beta testers.

Nominal output voltage 6.3v +/- 0.1v

Max. output current 1Amp. fuse protected.

Since I don't have a card reader with me I'll also leave the CR operation test for the Beta's ;-)
Total number of card passes before "BAT" and the like may be of interest.

Also the Wand is a somewhat "power hungry" peripheral which figures could be of interest for some users.

Questions and suggestions are welcome as usual.

Best wishes.

Diego.

[Cococollector]

I'm in for two as well.

We could carefully tape some dozens of mag cards together to reduce tedious manual work. With a little space in between. Was a spontaneous thought, but.. would that work?
We could even tape a dozen together into a ring for an endurance test (Les 24 Heures Des Cartes).
I better stop here...

[Namir]

Good work Diego!

Put me down for 2.

Namir

[Diego Diaz]

Hi there,

Things have gone really smooth along the week and I've finished the circuit boards of all 8 prototypes and three of the battery boards.

I'll be finishing the remaining 5 in the next couple of days.

Will keep the tag for these 8 units in the 100Eur; final price for the production units will be 120Eur. and registered worldwide shipping will be included in all cases as usual.

Since my trip back to Spain is shifted to Aug. 4th. I may try to ship the two first units to the Americas (US and Canada) from my current location in Dominican Republic.

Not sure if the Post Service here will allow me to ship *anything" containing a battery. (They're becoming very picky about such things lately)

Please, if you're in the Beta's list but have changed your mind, just let me know (here or to my email "clonix41@gmail.com") so I can offer it to another user.

In the picture of the current progress below, you can see a green tab taped to the edge of the battery board; this is to prevent the safety switch from being activated in transit.

Also, two spare 1Amp fuses are included with every pack (hopefully you'll never need them... ;-)

All the best!

Diego.

   

[Chr Yoko]

LiIon transportation is now carefully checked and needs to follow UN rules.

Post might reject your battery module as it is not self contained at all.
ie: Your pouch should be inside a closed container at least.
Can't you find a metallic small box to ship it into ?
Or 3D print a bespoke sealed box ?

The real issue is that the pouch is exposed and could be damaged during transportation.
It could get thermal runaway then and put fire to the truck , train , plane !

[Massimo Gnerucci]

(07-23-2023 11:26 PM)Diego Diaz Wrote:  Please, if you're in the Beta's list but have changed your mind, just let me know (here or to my email "clonix41@gmail.com") so I can offer it to another user.

Hi! Didn't change my mind, but still on holidays until 31/7.

[Sylvain Cote]

Great news!

Things to do before receiving the beta unit:

• Pay beta unit (check)
• Buy a balanced LIPO charger [SKYRC iMAX B6AC V2] (check)
• Buy a battery temperature sensor for the balanced LIPO charger (check)
• Buy a fire proof LIPO battery safe bag for when charging (check)
  

[Diego Diaz]

Hi all,

@Chr Yoko, It seems to me that the easiest solution will be to find a suitable small box and "insert" the battery pack before shipping. Hopefully, cheap enough to not affect the final cost.

@Massimo, Just in time, I'll be back in Spain on August 4. ;-)

@Sylvain, Nice point to get a safe bag to charge the pack when out of the calculator. Regarding the battery charger you've chosen, I'm afraid it is not suitable for this application.

This charger is intended for use mostly on heavy duty battery packs (up to 6S) with high current rate both in charge and discharge in the range of tens of Amps. and fast charging.

These batteries are common in the RC field: Drones and radio controlled vehicles. And since they're built using several unprotected cells (in series and/or parallel configurations) an active method of controlling (balancing) the charge of every cell is required; hence the complex type of charger.

The application for the HP-41 uses one single (protected) cell designed for low current operation (1Amp max).

The charger circuit (4057) takes care of the whole process and needs just a simple smartphone charger and a UCB-C cable. I've used my Samsung's charger along these days.

Due to the current limitation the charging process takes several hours but this ensures a minimal temperature rise. Slightly warmer around the USB-C connector is all it gets.

In the attached picture are detailed every IC and the protections applied.

Hope this clarifies the point.

All the best.

Diego.
   

[Chr Yoko]

Correct, no need of the great [SKYRC iMAX B6AC V2] with that small HP-41 pack because the pack has its own USB-C to Li-Ion charging circuit + an internal (to the pouch) BMS (Battery Management System) that will prevent over charging, undervoltage and over current.

The SKYRC charger is used for Li-Ion cells that do not have any BMS included as the charger is providing the required protections during charging if used correctly (many options into its menus). Better use such charger or you really need to know what you are doing. Also always use a protective fireproof bag as Lithium and the electrolytes will burn with an heavy white toxic smoke .

Most LiPo's pouches (and cylindrical 18650, 21700...) with no BMS are used for RC cars, planes, drones as it is necessary to get a maximum of Amperes out of the cell. Usual BMSs aren't able to provide all that current.
The SKYRC can also work with cells in series. It has a balancing connector : you can wire the balancing wires between each cell to manage the load balancing to make sure that all cells have the same voltage at the end of charging.

I use such charger on NiMh (you can chose the cells chemistries in the menu) for my home made packs on HP-75 and HP-97 without balancing. I can use also my variable power supply with charging voltage (ie:6V) and a max safe current (ie:500mA).

[Chr Yoko]

Transportation rules are under the UN 38.3 regulation.

The tests required :
https://www.tuvsud.com/en/-/media/global...t-38-3.pdf

With a cell INSIDE a device you need to follow that regulation :
Classe 9 – UN3481
with a mandatory label onto the parcel (you need to buy the official labels)

and OUTSIDE (or standalone) :
Classe 9 – UN3480
Not sure you can fly them anymore .... or via cargo plane only.

Basic rule (check the exact figure) : Never transport the cell fully charged, 30-50% Max of SOC. It will thus contain less energy, just in case...

You need to check the exact transport rules with your transport company and it may depend on the country IN/OUT.

Maybe a good solution would be to let people buy the pouch on Ally express or whatever supplier you have chosen. And deliver only the pack itself ?
Personally i would be interrested into the components BOM and boards CAD files, so i can build it by myself... I had such project but not enough time at moment.

[Sylvain Cote]

I have received my 82120D beta unit Friday afternoon.

First, this is a very well done battery pack, it fit perfectly, the insertion and removal from the 41 is very easy.

Upon reception, the first thing I did was to try the card reader, after 50 cards with the initial charge, no bat annunciator was displayed, impressive.

Then I plugged an Apple 120v 20W USB-C adapter into the battery pack for the night to have a full charged unit before starting the real tests.
Upon connection a small RED LED light up to indicate that unit is charging.
When I came back the next morning, a BLUE LED was light up to indicate that the unit was fully charged, nice.
Diego told me that his tests shows that the charging takes between 3h 30m to 4h 45m with a standard smartphone chargers.

My test setup is:

• HP-41CX half-nut , rev: 0:NFL 1:DCC
• rebuilt card reader, rev: CR-1G
• optical wand
  

I did the following tests:

1. read/write 305 magnetic cards
2. read 315 barcode program strips (the entire Games solution book)
3. the following test program has been running for 122h45m (updated on 2023-08-18 15h30 GMT-04:00 DST)
   

Still no BAT annunciator!

My goal is to read cards and run programs until the BAT annunciator light up.

This is way over and above the wildest expectation that I had.
Thank you Diego for solving my 40 years old issue about using the card reader with rechargeable batteries.

Sylvain

Edit: update run time

PS: test program ...

Code:

LBL "BTST"
  FIX 6
  0
  SETSW
  RUNSW
LBL 00
  RCLSW
  VIEW X
  FS? 49
    GTO 01
  -.1
  GETKEYX
  RDN
  X=0?
    GTO 00
LBL 01
  STOPSW
  RCLSW
  VIEW X
END

[Diego Diaz]

Hi Sylvain, all,

Thanks for sharing this info about your first tests.

I'm glad to know that the overall performance of the Power Bank is fairly positive.

I've also been running some endurance test with my Card Reader, currently over 350 card passes and still no "BAT" annunciator.

It's *normal* that some Card Readers require more power (mAmps) to run. I've measured my other two CR and found differences above 30% in peak current drain.

My best guess about it is that the motor/gears require mechanical adjustment and/or proper lubrication.

Look forward to see other Beta testers results running CL, NoV-64d, MAXX, HEPAX, IR printer; which seems to me the most power hungry devices.

On the mechanical side of the project, I've detected a small misalignment between the edge of the internal board and the tabs of the original* charging port cover. *(I've been reported that this doesn't happen with the 3D printed ones).

Anyhow, it has been addressed in the design of the production PCB. :-)

Also the connections between the Battery board and the circuit board will change from 6 to 8 Dupont connectors to improve mechanical strength. This change does not affect compatibility between the Battery Board and the Circuit Board of the Beta units; they will still can be used with the Production units and vice-versa.

Best wishes and have a nice week.

Diego.