Hi,
I have seen that it is possible to link 2 Arduino boards together and the information says that more can be added.
On the schematic it links ground->ground, 4->4 and 5->5 in serial, how can I link Arduino boards 3, 4 etc. is it the same pins?
I suspect on the master that I would need to somehow expand the connection ability of the ground, & pins 4 & 5?
Is there a simple connector I could use? It would in the end need to be user friendly as each board would act as a plugin.

Appreciate the steer.

Kind regards,
jB 

As they say (whoever they are) "If you can't stand the heat stay out of the kitchen".
Being ex military I too have a very dark sense of humour and the limo sounds like a great idea, except there would be room for the wife and kids and grand kids so can we leave that project until next month...

I have about 30% vision in 1 eye, nothing in the other. I tire very easily and often cannot get out of bed which was a primary consideration for this system for me.
My body is attacking itself so sometimes due to the pain my fingers are useless other times when the morphine kicks in I think I could run a marathon. It is all very hit and miss.

I want to do something like this project for my sanity and confidence, I admit to being an arduino virgin and am aware of electonics but have ordered a couple of books to bring me back up to speed. I forget things quickly but can remember trivia instantly.
So to start programming again I will need a manual by my side. Ten minutes later it will all come flooding back and off I go. The next day I have to think hard before I start again.

There you have me in a nutshell.
Dark, thick and slow. (Don't you dare call me Treacle, I can still remember some dirty tricks from the Army)... 

Kind regards,

jB   

Hi,

Totally agree this is great.
I have as yet not purchased a board or considered coding as I was investigating the possibilities before investing time and money.
I am disabled and partially sighted so have to regulate time on the PC for my eyes sake and also disability pensions sake on purchasing frivalous boys toys. 

I believe I mentioned earlier that normally about once a month I "boil" the batteries. This is, that I take the batteries up to 32-34V DC to "burn" off all of the sulphates and realign the system. This is called equalization. Normally the process flows in this fashion.

1.   Approximately 8 hours of "Bulk" charging that brings the batteries upto a topped up condition. 24-28V DC of charge.
2.   Approximately 2-4 hours of "Absorbtion" charging that deep charges the batteries, this is like the old mobile phone chargers where you got rid of battery memory and went back to using the whole battery rather than just parts of it to deliver output. 24-30V DC of charge.
3.   Approximately 0-N hours of "Float" charging just to add a bit of oomph to the batteries, but is also the precursor to stage 4, which on my system is manually selected. 24-28V DC of charge.
4.   Approximately 2-4 hours of "Equalization" charging, which desulphates the batteries. 32-34V DC of charge, the batteries bubble vigourously. Need gas caps.

Stages 1 & obviously 4 produce the most crud and as I use gas recycle caps I think it would be most prudent to remove the sensors during these phases, where possible. Gas recycling caps, reduces the amount of acid gas pushed out of the batteries which is quite noxious and flamable. I would have to experiment with the durability of sensors attached to a gas cap.

It would be great if the capsule could also contain a temperature, amperage and min / max depth guage.
Not sure how to attach photos of a battery and gas gap but will try during the day.

Kind regards to all,

jB 

Hi,

I have 2 banks of (12 x 2V DC = 24V DC) 1200ah Lead Acid Batteries as produced by Isofoton etc. They are solid plate, electrolyte activated. They are about 10cm square by about 100 cm high.

They are directly fed by a 3.5 Kv Wind Turbine (24V via a DC regulator)
I have 10 Solar Panels producing 1Kv which is fed into a Victron Blue 5000Kv 24V 50Hz Inverter Charger.
I have an 11Kv Kubuta Generator which is used when domestic drain is above certain tolerance such as Dish Washer, Power Showers. Additionally it is used to boil the batteries once a month to equalize them, therefore each battery is fitted with a gas recycling cap rather than the standard screw cap.

I had therefore thought that for initial trials I would use a standard screw cap to allow access t / from the hydrometer. Once proof of concept was shown I would move on to using the recycle caps which a fairly expensive.

I had also initially thought that maybe 1 sensor in each bank would suffice, but if the economics was correct ideally each battery should report its condition.
Which would also include its fluid level and current temperature.

A friend of mine is a big installer of domestic off grid systems and if I approached him with a product I am sure he would be able to sell these by the bucket load, especially if there was also a front-end solution, which was my ultimate aim. I wanted to produce a web based solution that would inform me about the overall condition of the batteries both individually and collectively, which could be accessed by both the end user and the off-site installer, maintainer...

So anything you can develop would be wonderful, bearing in mind I am an Arduino virgin...

Kind regards,

jB

Hi,

Thanks to all those that have pointed me further down the long road.
Seems I always choose the tougher projects in any new environment.

I would have thought by now someone would have developed a commercial hydrometer sensor.
Maybe if I manage it, I could get rich beyond my wildest dreams?

Kind regards,

jB 
PS The  is not coz I'm cool it's coz I'm partially sighted and the icon looks like me...

Hi to all,

This is my first post and first foray into Arduino.
I need to be able to remotely test the Specific Gravity of an array of Lead Acid Batteries used as the power source / storage from my Solar Panels and Wind Turbine.
Can anyone please advise me as to how to either make or where to purchase a hydrometer sensor from?

Thanks to all.
Kind regards,
jB