A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one
and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced
he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights
indicating the level of charge go into the amber zone and he thinks
it's about to run out of power. I reckon it should go a lot further
then he fears and then there's the question of charging the thing -
how long does it need?

I'm planning to take the thing for a run and see actually how far it
will go after an 8 hour charge but I wonder if anyone has any
experience of these chairs.

What type of batteries are they? - what's the mah?

What type of charger is he using?

On Sun, 11 Dec 2016 07:24:02 -0800 (PST), Murmansk
wrote:

A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power.
I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

How far it will go depends upon his weight and the degree of incline.
The manufacturers/sellers estimates are for a plastic garden gnome as
occupier and a perfect level surface and even then are wildly
optimistic.

Lead acid batteries discharge gradually until the voltage start to
fall and then go quickly. See
https://iceradar.wikispaces.com/file..._Discharge.JPG
for an example. His concern over being left stranded if the charge
indicator is amber may be justified. Unfortunately there is no
particular standard for the calibration of the devices.

Sealed Lead Acid are also delicate little flowers and do not tolerate
total discharge at all well. Given that he may have let it discharge
significantly in the past a service life of 2 years isn't at all
unreasonable and replacement may be sensible. Getting batteries from
the wheelchair supplier isn't necessary and is usually significantly
more expensive than getting them from an on-line or local battery
specialist. Batteries specified for deep discharge give some extra
protection against battery failure due to over discharging them, but
not much.

Charging time depends upon the charger type. For most leaving the
charger plugged in when the chair is not in use at home seems to give
the best results. From half to full charge usually takes 8-12 hours
but there is a lot of variability between chargers. The smaller and
lighter the charger the longer it is likely to take.

What type of batteries are they? - what's the mah?

What type of charger is he using?

These are very fair questions to which I'll attempt to find the answers

On Sunday, 11 December 2016 16:46:12 UTC, Murmansk wrote:
What type of batteries are they? - what's the mah?

What type of charger is he using?

These are very fair questions to which I'll attempt to find the answers

the relevant questions are
battery voltage & Ah
the charger's current output.


NT

On 11/12/2016 15:24, Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

I don't know the answer!

It seems a reasonable idea to take it for a run to test the battery
life. As others have said, the distance it will go will depend on the
weight of the occupant and the gradient - and probably the type of
surface. I imagine that the battery will get used up faster on loose
gravel than on smooth concrete.

I would suggest choosing a route which is typical of that used by the
owner, and noting how much further you can go once the battery indicator
enters the amber zone.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On Sun, 11 Dec 2016 17:03:14 +0000, Roger Mills
wrote:

I would suggest choosing a route which is typical of that used by the
owner, and noting how much further you can go once the battery indicator
enters the amber zone.

A route which circled your house may be better - finding out how far
the battery will go by ending up a mile or so out with no electricity
isn't wise, most electric wheelchairs do a good imitation of an
immovable (or at least movable only a very short distance) object once
the batteries fully discharge. Full discharge also knackers Sealed
Lead Acid batteries.

Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

Don't over look a poor meter. It is quite difficult to get an accurate
estimate of remaining charge simply from terminal voltage anyway and add
to that a cheap/nasty meter and the result could well be pessimistic.
Take a volt meter with you on the test run and see what voltage
corresponds to which meter reading.

On 11/12/2016 17:17, Bob Minchin wrote:
Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one
and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced
he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights
indicating the level of charge go into the amber zone and he thinks
it's about to run out of power. I reckon it should go a lot further
then he fears and then there's the question of charging the thing -
how long does it need?

I'm planning to take the thing for a run and see actually how far it
will go after an 8 hour charge but I wonder if anyone has any
experience of these chairs.

Don't over look a poor meter. It is quite difficult to get an accurate
estimate of remaining charge simply from terminal voltage anyway and add
to that a cheap/nasty meter and the result could well be pessimistic.
Take a volt meter with you on the test run and see what voltage
corresponds to which meter reading.

Except that a partially discharged battery will always show 12v off load?

I suppose the off-load voltage could be used as a reference and measure
the difference/drop when the battery is fully loaded.

On 11/12/2016 15:24, Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

What size? They vary from 12Ah to 120Ah. What is the battery type number?
Cheap batteries can have a much lower Ah capacity than stated, and often
don't last long.


He seems to want to buy some more batteries for it and I'm convinced he doesn't need t

o as we only got some a couple of years ago.

Whatever you do don't get batteries from a disability shop. Look at
battery suppliers on the internet.


He only uses it twice a week to go about 500 metres on each occasion.

A small chair with two 16Ah batteries will go four miles assuming
1. The surface is smooth (grass or rough surfaces reduce the range by
half or more)
2. The route does not involve much climbing
3. The person is not extremely heavy.
4. The person doesn't keep speeding up and slowing down all the time (as
some nervous people do).
5. The chair is in good working order. Check the front wheels to make
sure they turn freely. Check the steering pivots; if stiff they reduce
range. Check the brakes aren't binding. Inflatable tyres should be
really hard.

A large chair with two 100Ah batteries will go 20 miles if the same
parameters are obeyed.


His wanting new batteries is prompted by the fact that the lights indicating the level of c

harge go into the amber zone and he thinks it's about to run out of power.

It means nothing. Some chairs go to amber when the on-load voltage is
still 23.7V or more.

I reckon it should go a

lot further then he fears and then there's the question of charging
the thing - how long does it need?

It depends on the charger. A cheapo charger will never charge the
battery optimally. It might under- or -over charge.
A general point is that even when the machine says it's fully charged
what it actually means is 'useable'. For this and other reasons the
machine should be on charge every moment that it isn't actually in use.
A decent charger will never overcharge.
Google Numax 24V mobility chargers. I've had a few of these and they are
good. When you tell me the battery type and size I'll tell you which one
to buy.


I'm planning to take the thing for a run and see actually how far it will go after an 8 hour

charge but I wonder if anyone has any experience of these chairs.

No, put it on charge for 20 hours and then try it. Ideally check the
off-load voltage after an hour's rest after a full charge. It should be
no lower than 26.5V.

Bill

In article ,
Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one
and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he
doesn't need to as we only got some a couple of years ago.

It is perfectly possible they are past their best at two years old. Only
real way to know is to have them tested on a smart tester.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights
indicating the level of charge go into the amber zone and he thinks it's
about to run out of power. I reckon it should go a lot further then he
fears and then there's the question of charging the thing - how long
does it need?

I'd expect it to charge up overnight at worst. And switch off the charger
when full.

Does the handbook not give some indication of how much range left with the
various lights?

I'm planning to take the thing for a run and see actually how far it
will go after an 8 hour charge but I wonder if anyone has any experience
of these chairs.

Unlikely, given you haven't said the make and model. ;-)

--
*Avoid clichés like the plague. (They're old hat.) *

Dave Plowman London SW
To e-mail, change noise into sound.

Bill Wright submitted this idea :
No, put it on charge for 20 hours and then try it. Ideally check the off-load
voltage after an hour's rest after a full charge. It should be no lower than
26.5V.

My partners chair was little used, when she passed away it was around
12 months old. I have made use of it occaisionaly in the 18 months
since then, for trips where I would normally walk, but where some
weight needs to be carried - just to avoid getting the car out. One of
those trips is a mile downhill and a mile back up carrying 2x 17kg bags
of dog feed.

I pop it on charge after use and it replaces the used charge in an
hour. The charger is switch mode type and it cuts off at full charge,
so no point in leaving it connected permanently. Every month or so I
give it a boost, which takes just a few minutes to cutting off.

The remaining charge meter is almost useless. It seems to be just a
volt meter and the voltage goes up when off load, way down when
climbing a hill and under a heavy load.

On Sunday, 11 December 2016 16:25:19 UTC, Peter Parry wrote:
How far it will go depends upon his weight and the degree of incline.
The manufacturers/sellers estimates are for a plastic garden gnome as
occupier and a perfect level surface

and crawling at the speed of a Lucky Golden Hedgehog?

Owain

On 11/12/2016 19:30, Harry Bloomfield wrote:
Bill Wright submitted this idea :
No, put it on charge for 20 hours and then try it. Ideally check the
off-load voltage after an hour's rest after a full charge. It should
be no lower than 26.5V.

My partners chair was little used, when she passed away it was around 12
months old. I have made use of it occaisionaly in the 18 months since
then, for trips where I would normally walk, but where some weight needs
to be carried - just to avoid getting the car out. One of those trips is
a mile downhill and a mile back up carrying 2x 17kg bags of dog feed.

I pop it on charge after use and it replaces the used charge in an
hour. The charger is switch mode type and it cuts off at full charge, so
no point in leaving it connected permanently. Every month or so I give
it a boost, which takes just a few minutes to cutting off.

No, what the charger does (or should do) is switch to a safe slow
charge, to avoid overcharging. It will continue to charge for many hours
until eventually the charge rate becomes just a few mA. At the point
when the charger switches the battery is probably only 70 to 80% charged.

If you really are fully charging the battery after a one mile uphill run
in less than an hour the charge rate must be extremely high.

Since your journey is downhill for the first mile the chair will be
charging the battery regeneratively in that time unless it's a cheap or
old one.

Unless the charger is a crap one it's much better for the battery to
give it 24 hours at least, and 24 hours every month.

Bill

On 11/12/2016 18:36, Dave Plowman (News) wrote:

I'd expect it to charge up overnight at worst. And switch off the charger
when full.

No, leave it on if it's a good modern charger. It will just be providing
a few mA.
In fact I'll just go and have a look at the motorhome batteries. One
says 0.003, the other says 0.012. The second one was used briefly two
days ago. The batteries are 90Ah deep discharge types. The chargers are
16A. After deep discharge the charger starts at 17A and tapers over 36
hours to about 1A. Eventually the charger switches to 'float'.
I can't easily get at the other one but when I checked it the float
charge was 1mA. That's a 33Ah battery on an 8A charger.
I haven't checked the charge rates on the big chair (110Ah) since we got
it and I can't remember the figures, but when deeply discharged it takes
14 hours on an 8A charger for the green light to come on, and at that
point it is not fully charged. We found out the hard way. It needs half
a day further charge to be full.
We also have a small chair on a 4A charger. That starts at 4.6A and
after the green 'full' light comes on it continues at around 300mA,
tapering down to less than 1mA after a week.

Bill

On 11/12/2016 15:24, Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

My neighbour has one & can get to Chatham & back = 4 or 5 miles, return
journey up hill.

--
Dave - The Medway Handyman

Also be very careful that the connections are not corroded somewhere from
the outgassing of the batteries if they are of the normal non gellcell type.

Certainly it should go further than 500 yards but if there is voltage drop
across a corroded connection it will show up as dodgy on the system,
depending on where its measuring the voltage of course.
Too may variables. Surely the device has some minimum specs?
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Phil L" wrote in message
...
Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one
and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced
he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights
indicating the level of charge go into the amber zone and he thinks
it's about to run out of power. I reckon it should go a lot further
then he fears and then there's the question of charging the thing -
how long does it need?

I'm planning to take the thing for a run and see actually how far it
will go after an 8 hour charge but I wonder if anyone has any
experience of these chairs.

What type of batteries are they? - what's the mah?

What type of charger is he using?

Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.

If you do end up concluding that new batteries are needed then I can
thoroughly recommend buying from TAYNA online.

No commercial link just a satisfied customer - twice.

In article ,
Bill Wright wrote:
On 11/12/2016 18:36, Dave Plowman (News) wrote:

I'd expect it to charge up overnight at worst. And switch off the
charger when full.

No, leave it on if it's a good modern charger.

Was meaning it should do that itself. Even my pretty ancient and
inexpensive Lidl car starter pack which contains an SLA battery switches
off the charger when fully charged.

It will just be providing
a few mA.

If it's only providing a few mA, that's going to be neither here nor there
to the state of charge - except over a long time. Normally called a
maintenance or float charge to keep a battery that isn't actually in use
happy.

In fact I'll just go and have a look at the motorhome batteries. One
says 0.003, the other says 0.012. The second one was used briefly two
days ago. The batteries are 90Ah deep discharge types. The chargers are
16A. After deep discharge the charger starts at 17A and tapers over 36
hours to about 1A. Eventually the charger switches to 'float'.
I can't easily get at the other one but when I checked it the float
charge was 1mA. That's a 33Ah battery on an 8A charger.

Most leisure batteries are wet types. Don't wheelchairs have SLA (gel)
types because they might get overturned?

I haven't checked the charge rates on the big chair (110Ah) since we got
it and I can't remember the figures, but when deeply discharged it takes
14 hours on an 8A charger for the green light to come on, and at that
point it is not fully charged. We found out the hard way. It needs half
a day further charge to be full.

Sound like a poor charger. I'd say it would be a requirement to charge the
batteries overnight. Not effectively a full day. Think about it. ;-)

We also have a small chair on a 4A charger. That starts at 4.6A and
after the green 'full' light comes on it continues at around 300mA,
tapering down to less than 1mA after a week.

I'm sure there are all sorts of tricks to get the last 1% or whatever of
charge. But if that is crucial, just fit a larger battery?

Bill

--
*Just give me chocolate and nobody gets hurt

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Jethro_uk wrote:
On Mon, 12 Dec 2016 11:37:25 +0000, Dave Plowman (News) wrote:

Most leisure batteries are wet types. Don't wheelchairs have SLA (gel)
types because they might get overturned?

Not just that, but there are differences in profiles (or something). I
managed to fit some SLA UPS batteries to a scooter, which lasted 6
months. I was going to complain when I discovered I had ordered UPS
batteries - which were cheaper than scooter (golf buggy) batteries. I
think scooter/buggy batteries are designed to deep-cycle, whereas UPS
batteries aren't.

Not sure this applies to gel types in quite the same way as it does to wet.
What make were they?

Depending on where you are, a UPS could get quite a pounding. Do they say
batteries for this use will only stand a few cycles?

I've not seen a good make SLA like Yuasa marked for actual usage.

--
*If a pig loses its voice, is it disgruntled?

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Jethro_uk wrote:
On Mon, 12 Dec 2016 11:37:25 +0000, Dave Plowman (News) wrote:

Most leisure batteries are wet types. Don't wheelchairs have SLA (gel)
types because they might get overturned?

Not just that, but there are differences in profiles (or something). I
managed to fit some SLA UPS batteries to a scooter, which lasted 6
months. I was going to complain when I discovered I had ordered UPS
batteries - which were cheaper than scooter (golf buggy) batteries. I
think scooter/buggy batteries are designed to deep-cycle, whereas UPS
batteries aren't.

A common mistake. The other common mistake is buying cheap brands, you get less capacity and half the life. Yuasa are good - obviously you need the golf buggy or disability scooter rated ones. If the machine is ever to go on an airplane they need to be disability scooter rated. IIRC the relevant Yuasa types are REC and YPC.


NT

In article ,
wrote:
In article ,
Jethro_uk wrote:
On Mon, 12 Dec 2016 11:37:25 +0000, Dave Plowman (News) wrote:

Most leisure batteries are wet types. Don't wheelchairs have SLA (gel)
types because they might get overturned?

Not just that, but there are differences in profiles (or something). I
managed to fit some SLA UPS batteries to a scooter, which lasted 6
months. I was going to complain when I discovered I had ordered UPS
batteries - which were cheaper than scooter (golf buggy) batteries. I
think scooter/buggy batteries are designed to deep-cycle, whereas UPS
batteries aren't.

A common mistake. The other common mistake is buying cheap brands, you
get less capacity and half the life. Yuasa are good - obviously you need
the golf buggy or disability scooter rated ones. If the machine is ever
to go on an airplane they need to be disability scooter rated. IIRC the
relevant Yuasa types are REC and YPC.


Yuasa REC are absorbed glass mat construction. YPC more a gel type.

They'd both be suitable for wheelchair use I'd guess, but the chargers
could well be different.

--
*Drugs may lead to nowhere, but at least it's the scenic route *

Dave Plowman London SW
To e-mail, change noise into sound.

On 12/12/2016 11:37, Dave Plowman (News) wrote:

I haven't checked the charge rates on the big chair (110Ah) since we got
it and I can't remember the figures, but when deeply discharged it takes
14 hours on an 8A charger for the green light to come on, and at that
point it is not fully charged. We found out the hard way. It needs half
a day further charge to be full.

Sound like a poor charger. I'd say it would be a requirement to charge the
batteries overnight. Not effectively a full day. Think about it. ;-)

It's the charger supplied with the chair. I think the assumption is that
the user will not use such a big chair all day long. With a range of 20
miles and a max speed of 8mph it isn't likely to be in use for more than
three or four hours a day. I suppose if anyone had a problem they could
simply use a 16A charger.


A small chair used indoors and out might get longer hours of use though.


We also have a small chair on a 4A charger. That starts at 4.6A and
after the green 'full' light comes on it continues at around 300mA,
tapering down to less than 1mA after a week.

I'm sure there are all sorts of tricks to get the last 1% or whatever of
charge. But if that is crucial, just fit a larger battery?

No room. Weight is critical with small chairs. It isn't the last 1%,
it's the last 20%.

Bill

On Monday, 12 December 2016 19:37:22 UTC, Bill Wright wrote:
On 12/12/2016 11:37, Dave Plowman (News) wrote:

I haven't checked the charge rates on the big chair (110Ah) since we got
it and I can't remember the figures, but when deeply discharged it takes
14 hours on an 8A charger for the green light to come on, and at that
point it is not fully charged. We found out the hard way. It needs half
a day further charge to be full.

Sound like a poor charger. I'd say it would be a requirement to charge the
batteries overnight. Not effectively a full day. Think about it. ;-)

It's the charger supplied with the chair. I think the assumption is that
the user will not use such a big chair all day long. With a range of 20
miles and a max speed of 8mph it isn't likely to be in use for more than
three or four hours a day. I suppose if anyone had a problem they could
simply use a 16A charger.


A small chair used indoors and out might get longer hours of use though.

There's a good price differential between low & high current chargers, and competition is based on price to a significant extent. So not surprising the customer's assumptions aren't always met.

We also have a small chair on a 4A charger. That starts at 4.6A and
after the green 'full' light comes on it continues at around 300mA,
tapering down to less than 1mA after a week.

I'm sure there are all sorts of tricks to get the last 1% or whatever of
charge. But if that is crucial, just fit a larger battery?

No room. Weight is critical with small chairs. It isn't the last 1%,
it's the last 20%.

Bill

Indeed.


NT

Just to update, I can report that the two batteries are 12 V 34Ah and the charger is 24V 4 Amps

On Monday, 19 December 2016 20:50:37 UTC, Murmansk wrote:
Just to update, I can report that the two batteries are 12 V 34Ah and the charger is 24V 4 Amps

So charge time around 9 hrs or longer. Range 3 miles of hill, rather more on the flat.


NT

In article ,
wrote:
On Monday, 19 December 2016 20:50:37 UTC, Murmansk wrote:
Just to update, I can report that the two batteries are 12 V 34Ah and
the charger is 24V 4 Amps

So charge time around 9 hrs or longer. Range 3 miles of hill, rather
more on the flat.


Surely any charger which wouldn't re-charge wheelchair batteries when the
user was sleeping (or whatever) overnight would be pretty useless? But if
you wanted to fast charge such batteries you'd need to change to a
different (and much more expensive) type?

--
*Do infants enjoy infancy as much as adults enjoy adultery?

Dave Plowman London SW
To e-mail, change noise into sound.

Difficult one this, as the law that lead acid batteries follow seems often
not to be what was expected.
I had a battery lawnmower which said it was fully charged but only did half
the lawn. However shove it on a bigger old fashioned charger and leave it
overnight and it could do the whole lawn.
I no longer have it, since I can no longer see where I'm mowing which is
rather important.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Bill Wright" wrote in message
news
On 12/12/2016 11:37, Dave Plowman (News) wrote:

I haven't checked the charge rates on the big chair (110Ah) since we got
it and I can't remember the figures, but when deeply discharged it takes
14 hours on an 8A charger for the green light to come on, and at that
point it is not fully charged. We found out the hard way. It needs half
a day further charge to be full.

Sound like a poor charger. I'd say it would be a requirement to charge
the
batteries overnight. Not effectively a full day. Think about it. ;-)

It's the charger supplied with the chair. I think the assumption is that
the user will not use such a big chair all day long. With a range of 20
miles and a max speed of 8mph it isn't likely to be in use for more than
three or four hours a day. I suppose if anyone had a problem they could
simply use a 16A charger.


A small chair used indoors and out might get longer hours of use though.


We also have a small chair on a 4A charger. That starts at 4.6A and
after the green 'full' light comes on it continues at around 300mA,
tapering down to less than 1mA after a week.

I'm sure there are all sorts of tricks to get the last 1% or whatever of
charge. But if that is crucial, just fit a larger battery?

No room. Weight is critical with small chairs. It isn't the last 1%, it's
the last 20%.

Bill

On 12/12/2016 12:06, Jethro_uk wrote:
On Mon, 12 Dec 2016 11:37:25 +0000, Dave Plowman (News) wrote:

Most leisure batteries are wet types. Don't wheelchairs have SLA (gel)
types because they might get overturned?

Not just that, but there are differences in profiles (or something). I
managed to fit some SLA UPS batteries to a scooter, which lasted 6
months. I was going to complain when I discovered I had ordered UPS
batteries - which were cheaper than scooter (golf buggy) batteries. I
think scooter/buggy batteries are designed to deep-cycle, whereas UPS
batteries aren't.

They are also designed more robustly to tolerate the vibration and
shocks that come from being in a vehicle whereas the UPS ones are purely
optimised for energy density and don't like hard knocks.

--
Regards,
Martin Brown

On 06/01/17 19:47, Brian Gaff wrote:
Difficult one this, as the law that lead acid batteries follow seems often
not to be what was expected.
I had a battery lawnmower which said it was fully charged but only did half
the lawn. However shove it on a bigger old fashioned charger and leave it
overnight and it could do the whole lawn.
I no longer have it, since I can no longer see where I'm mowing which is
rather important.
Brian

get a Polamatic!

On 12/11/2016 3:24 PM, Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights indicating the level of charge go into the amber zone and he thinks it's about to run out of power. I reckon it should go a lot further then he fears and then there's the question of charging the thing - how long does it need?

I'm planning to take the thing for a run and see actually how far it will go after an 8 hour charge but I wonder if anyone has any experience of these chairs.


Campaign to bring back the Invacar! Brexit-friendly!

https://en.wikipedia.org/wiki/Invacar

On Friday, 6 January 2017 19:12:56 UTC, newshound wrote:

Campaign to bring back the Invacar! Brexit-friendly!

https://en.wikipedia.org/wiki/Invacar

Please god no. Give them all to people in India.


NT

On 06/01/17 21:12, newshound wrote:
On 12/11/2016 3:24 PM, Murmansk wrote:
A friend of mine has an electric wheelchair, it's a cheap Chinese one
and it has two lead acid batteries.

He seems to want to buy some more batteries for it and I'm convinced
he doesn't need to as we only got some a couple of years ago.

He only uses it twice a week to go about 500 metres on each occasion.

His wanting new batteries is prompted by the fact that the lights
indicating the level of charge go into the amber zone and he thinks
it's about to run out of power. I reckon it should go a lot further
then he fears and then there's the question of charging the thing -
how long does it need?

I'm planning to take the thing for a run and see actually how far it
will go after an 8 hour charge but I wonder if anyone has any
experience of these chairs.


Campaign to bring back the Invacar! Brexit-friendly!

https://en.wikipedia.org/wiki/Invacar

Ah! The original SpasWagen!