Mr. Wright's question about mobility scooter batteries has poked me into
asking this again.

1) I have a 12v towbar winch, which I need to cable to the front of the
Disco.
2) This vehicle tends to sit for weeks unused, so I'd like to be able to
plug in a charger in the garage and run a cable out to the car to put it
on charge in the inevitable rain.
3) I seem to be the only family member with a charger. Last time I had a
flat battery I had to ring round to recover the chargers. I seem to have
lost the 2 mains extension reels that they borrowed with the chargers.

It seems to me that something like a 30foot length of cable with
something like Anderson connectors on each end and a few adapters to
croc clips etc would be a useful thing to have handy. I gather Anderson
connectors are used to charge mobility scooters.

Winch current draw depends on the load, but apparently can range from
10A up to 90A for short periods.

2 questions: These connectors are said to be reversible. I can't get my
head round whether there could be any problem if they were lent out. If
the extension cable were connected the wrong way round, it would
presumably have + on black and - on red, but this would be corrected in
the adapters?

My guess is that either 4mm 41A or 6mm 53A stranded cable would be good
enough for the intermittent winch current in the open air, but I'm not
clear what size connectors would fit, or how easy this cable would be to
carry, store or handle.

Has anyone done this sort of thing?
--
Bill

What's the rated output of the charger? The cable from the garage to the
car shouldn't need to carry more than that. Only the cables from the
winch to the car battery will need to carry the full winch current.

If your charger is one of those start-and-charge things, then it'll be
able to tax the extension cable more heavily, but only very short-term.
Then your enemy will be voltage drop rather than cable current rating,
so the length becomes important.

Cheers,

Colin.

On 28/07/2014 11:48, Colin Stamp wrote:
What's the rated output of the charger? The cable from the garage to the
car shouldn't need to carry more than that.

Be careful, if we're talking about an ordinary single-phase
transformer-plus-bridge-rectifier type of charger (no smoothing of the
DC output) the RMS output current in the cable will be significantly
more than the mean DC current, due to the peaky waveform.

I'd advise rating the cable at least a factor of two above the rated
mean DC output, to play safe. Voltage drop considerations may dictate
that an more in any case.

--
Andy

On Mon, 28 Jul 2014 10:47:43 +0100, Bill wrote:

I gather Anderson
connectors are used to charge mobility scooters.

All I have come across use 3 pin XLR.

In message , Peter Parry
writes
On Mon, 28 Jul 2014 10:47:43 +0100, Bill wrote:

I gather Anderson
connectors are used to charge mobility scooters.

All I have come across use 3 pin XLR.


It looks a though some use XLR and some these Anderson connectors, but
I've never delved into this before, and don't know anyone with a
scooter.

XLR's were my original thought as I could just select a mic cable for
the charger operations, but I don't think that the 15A rating is enough
for the winch.
--
Bill

On 28/07/2014 13:46, Andy Wade wrote:
On 28/07/2014 11:48, Colin Stamp wrote:
What's the rated output of the charger? The cable from the garage to the
car shouldn't need to carry more than that.

Be careful, if we're talking about an ordinary single-phase
transformer-plus-bridge-rectifier type of charger (no smoothing of the
DC output) the RMS output current in the cable will be significantly
more than the mean DC current, due to the peaky waveform.

I'd advise rating the cable at least a factor of two above the rated
mean DC output, to play safe.

That's a bit further than I'd go - I'm guessing the number on the front
of that type of charger will be measured by whatever scheme makes it
highest, to the point of outright fraud. Still, as you say, better safe
than sorry.

Voltage drop considerations may dictate
that an more in any case.

Indeed. Particularly if it's an "Intelligent" charger, voltage drop will
be critical.

On the other hand, it could be a "charger" like this...

https://www.youtube.com/watch?v=-0RxmHgOVwc

In which case, you could probably use a mile of bell wire ;o)

Cheers,

Colin.

In message , Andy Wade
writes
On 28/07/2014 11:48, Colin Stamp wrote:
What's the rated output of the charger? The cable from the garage to the
car shouldn't need to carry more than that.

Be careful, if we're talking about an ordinary single-phase
transformer-plus-bridge-rectifier type of charger (no smoothing of the
DC output) the RMS output current in the cable will be significantly
more than the mean DC current, due to the peaky waveform.

I'd advise rating the cable at least a factor of two above the rated
mean DC output, to play safe. Voltage drop considerations may dictate
that an more in any case.

My chargers are just some cheap automatic things from Wickes or Aldi (I
hate and never understand the row of LED's), and the old little 6A
selenium rectifier one which had a nice meter on the front until my
daughter dropped it. It never bothered me that the case had melted above
the rectifier.
--
Bill

In message , Huge
writes
On 2014-07-28, Bill wrote:

2 questions: These connectors are said to be reversible. I can't get my
head round whether there could be any problem if they were lent out. If
the extension cable were connected the wrong way round, it would
presumably have + on black and - on red, but this would be corrected in
the adapters?

Anderson connectors are hermaphroditic (IOW, they all fit together - there
are no male & female connectors). It is impossible for them to be
connected "the wrong way round". What is possible is to wire them the
wrong way round, but providing both ends of the extension are wired the
same way round, it shouldn't matter. But if you want the cable colours
correct, I suggest you follow the standard;

http://www.powerwerx.com/assembly.asp

Thanks, that looks very useful. I'm still not sure how the hermaphrodite
thing works in practice, but I do think I'm getting more stupid with
age.

I think a 40A cable rating ought to be OK, so all I need to do is match
the cable to the connector size.

The other item I've needed to power was a tyre pump for the boat trailer
at some distance from the car. When I used an Aldi 3-way cigar socket
cable as an extension lead, I burnt my hand on the plug as I pulled it
out of the socket. The fuse had just blown and the cable was turning
nicely crisp.
--
Bill

In article , Bill
scribeth thus
In message , Peter Parry
writes
On Mon, 28 Jul 2014 10:47:43 +0100, Bill wrote:

I gather Anderson
connectors are used to charge mobility scooters.

All I have come across use 3 pin XLR.


It looks a though some use XLR and some these Anderson connectors, but
I've never delved into this before, and don't know anyone with a
scooter.

XLR's were my original thought as I could just select a mic cable for
the charger operations, but I don't think that the 15A rating is enough
for the winch.

There are bigger ones around the EP series or the Speakon connectors are
good...
--
Tony Sayer

On 28/07/2014 11:58, Huge wrote:
On 2014-07-28, Bill wrote:

2 questions: These connectors are said to be reversible. I can't get my
head round whether there could be any problem if they were lent out. If
the extension cable were connected the wrong way round, it would
presumably have + on black and - on red, but this would be corrected in
the adapters?

Anderson connectors are hermaphroditic (IOW, they all fit together - there
are no male & female connectors).

AAMOI they can be made m/f.

I used to sell Wetrok scrubber drier machines. The batteries were
connected to the machine via Anderson connectors. The connector from
the batteries had a pin & the connectors from the machine and the
charger had a hole. This was to prevent the charger being connected
directly to the machine and it's electronics.

I recall one cheapskate, know it all, contractor refusing our quote to
replace a set of batteries, claiming he could get a better price
elsewhere. The cheap supplier fitted normal Anderson connectors and the
operator connected the charger directly to the machine - burning out
about £600 worth of circuit boards etc.


--
Dave - The Medway Handyman www.medwayhandyman.co.uk