Charging

Power wheelchair board for REAL info!

POWERCHAIR MENU! www.wheelchairdriver.com/powerchair-stuff.htm

Re: Charging

Postby Burgerman » 13 Sep 2021, 11:25

See this?
It takes hundreds of amps to start a vans diesel engine. Thats why it needs a minimum 480A cranking amp rating on the battery according to the vans manufacturer. This one belongs to one of my carers. It had its lights left on all nght and is a winter morning. I jumped it with my chair. So again it takes hundreds of amps to both pull up the dead battery and additionally to start the engine on top. In the past I have measured similar operations and its a strong 200+A to crank in summer. Hell the heater plugs alone take 35A!

But 50A anderson not even warm. And theres 4 here! 100A fuse in loom, no problem. Because the high cranking current does not last long enough to blow the fuse either...

http://www.wheelchairdriver.com/gopro/starter.mp4
User avatar
Burgerman
Site Admin
 
Posts: 56968
Joined: 27 May 2008, 21:24
Location: United Kingdom

Re: Charging

Postby davidpaul » 13 Sep 2021, 15:52

Are the automotive crimp type spade connecter still the only option for plugging in to the control module ?
davidpaul
 
Posts: 256
Joined: 17 Jun 2013, 21:21
Location: Camborne, Cornwall

Re: Charging

Postby Burgerman » 13 Sep 2021, 22:00

Or ebay for a battery loom.
User avatar
Burgerman
Site Admin
 
Posts: 56968
Joined: 27 May 2008, 21:24
Location: United Kingdom

Re: Charging

Postby Fred005 » 15 Sep 2021, 08:30

Hi.

Supposing a LiFePo4 configuration with a good charger wich will make a right cells balance.
Without the use of any BMS, how could I have an automatic switch off of my main power when 1, or more but at least 1 cell voltage will reach to the low voltage setting ?

Thanks.
User avatar
Fred005
 
Posts: 161
Joined: 28 Apr 2021, 15:25
Location: Ancelle, South East France

Re: Charging

Postby woodygb » 15 Sep 2021, 08:50

You could purchase a battery monitor with an audible alarm...this would warn you when the cell / cells are approaching a voltage cut off point.

The following is an EXAMPLE ...NOT A RECOMMENDATION.

https://www.ebay.co.uk/itm/323150448067 ... 4d88e9f2a3
An expert is a person who has made all the mistakes that can be made in a very narrow field.
Niels Bohr
User avatar
woodygb
 
Posts: 6601
Joined: 12 Mar 2011, 18:45
Location: Bedford UK

Re: Charging

Postby Fred005 » 15 Sep 2021, 09:22

I had that in mind. It's a good idea.
However, if possible, I'll prefer an automatic switch off, as a BMS can do.
Why ?
Because of, most of the time when I'm hiking with my X8, it's I need 100% or so concentration about the track where I'm.
Very very often, on my left or right (sometime left and right) there is a huge precipice, and watching a monitor is not safe a bit.
Ok you'll say me if the main power will switch off in this kind of place, I'll have to manage some big problems. You're right. But if I can save my cells it's 1 problem solved.

So, it's why an auto switch off will be welcome for me/my need.
User avatar
Fred005
 
Posts: 161
Joined: 28 Apr 2021, 15:25
Location: Ancelle, South East France

Re: Charging

Postby woodygb » 15 Sep 2021, 10:29

The AUDIBLE alarm removes the need for you to watch a monitor and could be set to warn you when approaching the cut off limit...thus you should have plenty of time, to make an informed decision about what you should do next.
An expert is a person who has made all the mistakes that can be made in a very narrow field.
Niels Bohr
User avatar
woodygb
 
Posts: 6601
Joined: 12 Mar 2011, 18:45
Location: Bedford UK

Re: Charging

Postby Fred005 » 15 Sep 2021, 10:43

Yes, I ubderstand you.
However no solution for an auto switch off ... ?

If an audible/visual alarm can be powered on, it could be possible to send information to a power relay, no ?
User avatar
Fred005
 
Posts: 161
Joined: 28 Apr 2021, 15:25
Location: Ancelle, South East France

Re: Charging

Postby woodygb » 15 Sep 2021, 11:08

Fred005 wrote:Yes, I ubderstand you.
However no solution for an auto switch off ... ?

If an audible/visual alarm can be powered on, it could be possible to send information to a power relay, no ?


Yes ...The signal from the alarm could be recognised by an Arduino or similar device ... you could even program in a pre-determined delay ...and then action would be taken to turn ON/OFF a suitable sized contactor.
An expert is a person who has made all the mistakes that can be made in a very narrow field.
Niels Bohr
User avatar
woodygb
 
Posts: 6601
Joined: 12 Mar 2011, 18:45
Location: Bedford UK

Re: Charging

Postby shirley_hkg » 15 Sep 2021, 13:39


① Those cell monitors drain the first two cells , so will mess up the pack.

② Your worry seems unnecessary if you had a pack large enough , like most of us did here.

③ Install a £25 adjustable BMS instead , to power a contactor that controls the main output.

④ Avoid to output via BMS directly , and be able to flip the contactor manually to continue in case of emergency.
shirley_hkg
 
Posts: 3115
Joined: 31 Dec 2010, 13:42

Re: Charging

Postby Fred005 » 15 Sep 2021, 14:31

shirley_hkg wrote:① Those cell monitors drain the first two cells , so will mess up the pack. Thanks for this important information.

② Your worry seems unnecessary if you had a pack large enough , like most of us did here.My worry is not unnecessary, believe me. I never know how long will my hike be, because of many uncontroled parameters.

③ Install a £25 adjustable BMS instead , to power a contactor that controls the main output.That is what I need, EXACTELY ! Do you think to one BMS or do you have links, please ?

④ Avoid to output via BMS directly , and be able to flip the contactor manually to continue in case of emergency.It could be a good idea. A very good one.


Thanks for your help
User avatar
Fred005
 
Posts: 161
Joined: 28 Apr 2021, 15:25
Location: Ancelle, South East France

Re: Charging

Postby shirley_hkg » 15 Sep 2021, 14:42

cheers
Attachments
IMG-20210915-WA0025.jpg
IMG-20210915-WA0026.jpg
shirley_hkg
 
Posts: 3115
Joined: 31 Dec 2010, 13:42

Re: Charging

Postby Fred005 » 15 Sep 2021, 15:35

Thanks for the photo.
If you have a link about the BMS you were speaking, it'll be fine.
User avatar
Fred005
 
Posts: 161
Joined: 28 Apr 2021, 15:25
Location: Ancelle, South East France

Previous

Return to Everything Powerchair

Who is online

Users browsing this forum: ex-Gooserider, PowerUser and 19 guests

 

  eXTReMe Tracker