Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

On 31/01/2018 18:32, ss wrote:
Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

We might, of course, wonder why it has failed so catastrophically.

Before spending a lot of time sourcing a fuse and doing a repair, I
would be inclined to pop an ammeter with a reasonably high range across
the location. Even cheap DVMs normally have an internal fuse which
should protect them if (say) there is now mains across the two sides.

On 31/01/18 18:39, newshound wrote:
On 31/01/2018 18:32, ss wrote:
Charger for a mobility scooter. One charger not working, I opened it
up and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

We might, of course, wonder why it has failed so catastrophically.

Before spending a lot of time sourcing a fuse and doing a repair, I
would be inclined to pop an ammeter with a reasonably high range across
the location. Even cheap DVMs normally have an internal fuse which
should protect them if (say) there is now mains across the two sides.
Is it just me, or does that look like it's been bodged and there should
be a fuseholder on that board with a cartridge fuse?

ss wrote:

looks like 3A/2500AR

3A 250V AC

Any letters such as F, T or S on the remnants of the end cap?

On Wed, 31 Jan 2018 19:03:22 +0000, Andy Burns
wrote:

ss wrote:

looks like 3A/2500AR

3A 250V AC

Any letters such as F, T or S on the remnants of the end cap?

Fairly academic really.

The state of the fuse suggests that someone needing advice on how to
identify an antisurge fuse, would not be in a good position to find
the fault that caused that problem.

The only hope is that the event was caused by a spike initiating a
crowbar, or a "self healing" suppression cap, tranzorb etc.

A slim chance methinks!


AB

On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:

Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who knows. I suspect the latter is more likely.


NT

On Wed, 31 Jan 2018 11:34:40 -0800 (PST), wrote:

On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:

Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who knows. I suspect the latter is more likely.


NT
The replacement almost certainly wont work.

Trying to solder directly to the end caps of a 20mm glass fuse is
difficult, unless the mp of solder has changed a lot.

The current taking the thing out would be quite impressive.

AB

On Wednesday, 31 January 2018 19:54:26 UTC, Archibald Tarquin Blenkinsopp wrote:
On Wed, 31 Jan 2018 11:34:40 -0800 (PST), tabbypurr wrote:
On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:


Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who knows. I suspect the latter is more likely.

The replacement almost certainly wont work.

Trying to solder directly to the end caps of a 20mm glass fuse is
difficult, unless the mp of solder has changed a lot.

The current taking the thing out would be quite impressive.

AB

for testing just clip it in place. But like you said. I was wondering if there might be a chance it got connected to the battery the wrong way round, but it seems unlikely.


NT

I cannot see the picture, but is it a switch mode device or a good old
analogue supply?
If the latter the most common fault is the bridge rectifiers which are
commonly under specified for spikes in current etc.

If its swwitch mode then it might be possible to get a new module, but I've
seenin the past that companies have cut costs by fitting a soldered in fuse
as of course they never blow do they? :-)

Is the company that made the device still around?
Brian

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

Blind user, so no pictures please!
"Chris Bartram" wrote in message
news
On 31/01/18 18:39, newshound wrote:
On 31/01/2018 18:32, ss wrote:
Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

We might, of course, wonder why it has failed so catastrophically.

Before spending a lot of time sourcing a fuse and doing a repair, I would
be inclined to pop an ammeter with a reasonably high range across the
location. Even cheap DVMs normally have an internal fuse which should
protect them if (say) there is now mains across the two sides.
Is it just me, or does that look like it's been bodged and there should be
a fuseholder on that board with a cartridge fuse?

Yes if its directly onto the mains wire a 100 watt light bulb across it
first and look for smoke....:-)

Brian

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

Blind user, so no pictures please!
wrote in message
...
On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:

Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who knows.
I suspect the latter is more likely.


NT

On Wed, 31 Jan 2018 19:53:50 +0000, Archibald Tarquin Blenkinsopp
wrote:

Trying to solder directly to the end caps of a 20mm glass fuse is
difficult, unless the mp of solder has changed a lot.

So much easier to use a "leaded fuse", also "Fuses with Leads (Through Hole)"...


Thomas Prufer

You can get wire ended fuses though.
Brian

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

Blind user, so no pictures please!
"Archibald Tarquin Blenkinsopp" wrote in
message ...
On Wed, 31 Jan 2018 11:34:40 -0800 (PST), wrote:

On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:

Charger for a mobility scooter. One charger not working, I opened it up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who knows.
I suspect the latter is more likely.


NT
The replacement almost certainly wont work.

Trying to solder directly to the end caps of a 20mm glass fuse is
difficult, unless the mp of solder has changed a lot.

The current taking the thing out would be quite impressive.

AB

It would be interesting to look at the print side of the pcb to see if any
track is left. This is what did for the pcb on my old washing machine in the
end, fried track syndrome.
Brian

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

Blind user, so no pictures please!
wrote in message
...
On Wednesday, 31 January 2018 19:54:26 UTC, Archibald Tarquin Blenkinsopp
wrote:
On Wed, 31 Jan 2018 11:34:40 -0800 (PST), tabbypurr wrote:
On Wednesday, 31 January 2018 18:32:16 UTC, ss wrote:


Charger for a mobility scooter. One charger not working, I opened it
up
and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

it's a 3A fuse. Whether it'll then work or the replacement blow who
knows. I suspect the latter is more likely.

The replacement almost certainly wont work.

Trying to solder directly to the end caps of a 20mm glass fuse is
difficult, unless the mp of solder has changed a lot.

The current taking the thing out would be quite impressive.

AB

for testing just clip it in place. But like you said. I was wondering if
there might be a chance it got connected to the battery the wrong way
round, but it seems unlikely.


NT

On 31/01/2018 19:03, Andy Burns wrote:
ss wrote:

looks like 3A/2500AR

3A 250V AC

Any letters such as F, T or S on the remnants of the end cap?

On the end of the matal cap for the one with remnants of what appears to
be a glass fuse it has TAP
I cant see any other writing.

On 31/01/2018 20:08, Brian Gaff wrote:
Yes if its directly onto the mains wire a 100 watt light bulb across it
first and look for smoke....:-)

Brian

Without going in to the detail as I covered in a previous post the
scooter was FILs and he had an uncanny knack of just looking at
something and it broke,,,mobiles,computers, hearing aids, TV, set the
microwave on fire, he would pull plugs out of sockets by the cable, he
was a nightmare.

Anyhow his scooter has 2 chargers, 1 he lost the fuse (ordered ebay) and
the other (this one) who knows what he done. I have replaced the
batteries in the scooter and it works good and I will be selling it
locally for just above what it costs to get it all going, if I need to
buy another charger so be it but if I can keep the cost down its a
better buy for some old buddy.

So if I replace a fuse and it blows the charger I aint too bothered, I
just need to know what I am looking to replace.

ss wrote:

he had an uncanny knack of just looking at something and it broke

So do you think the fuse could have been physically damaged, rather than
blowing?

On Wed, 31 Jan 2018 21:41:24 +0000, Andy Burns wrote:

So do you think the fuse could have been physically damaged, rather than
blowing?

Possibly the charger output was shorted?


Thomas Prufer

On 31/01/2018 21:41, Andy Burns wrote:
ss wrote:

he had an uncanny knack of just looking at something and it broke

So do you think the fuse could have been physically damaged, rather than
blowing?

I dont think by accessing it, but more than likely dropped it a few
times or ran over it in his scooter.

On Wed, 31 Jan 2018 22:56:11 +0100, Thomas Prufer
wrote:

Possibly the charger output was shorted?

.... and the photo shows a NTC. Those are sometimes used as an inrush current
limiter. Switching the charger on and off frequently in a short time can defeat
the NTC, causing the fuse to blow.

Replace the fuse, and see!


Thomas Prufer

On 31/01/2018 21:41, Andy Burns wrote:
ss wrote:

he had an uncanny knack of just looking at something and it broke

So do you think the fuse could have been physically damaged, rather than
blowing?

By the looks of the picture the fuse detonated with considerable force.
I expect an insane current flowed briefly. It may do so again if the
fault was permanent as opposed to a transient dead short of the output.

A lash up with a 3A mains fuse is worth a try but be prepared for the
magic smoke coming out or worse. You don't want it starting a fire.

I'd conduct any tests outdoors and wear eye protection. YMMV

--
Regards,
Martin Brown

On 31/01/2018 22:30, Martin Brown wrote:
A lash up with a 3A mains fuse is worth a try but be prepared for the
magic smoke coming out or worse. You don't want it starting a fire.

I'd conduct any tests outdoors and wear eye protection. YMMV

No problem with that it will be at the end of a long extension lead out
the back garden.

As for the 3A fuse, looking at the remains of the old one would I be
correct in saying it was in the form of an upside down U shape, as I see
there are 2 points of damage, the remains of a glass fuse and then the
longish wire with just a cap on it, I presume these were connected at
one point and I basically bridge that gap with the fuse.

On Wednesday, 31 January 2018 21:30:44 UTC, ss wrote:
On 31/01/2018 20:08, Brian Gaff wrote:
Yes if its directly onto the mains wire a 100 watt light bulb across it
first and look for smoke....:-)

Brian

Without going in to the detail as I covered in a previous post the
scooter was FILs and he had an uncanny knack of just looking at
something and it broke,,,mobiles,computers, hearing aids, TV, set the
microwave on fire, he would pull plugs out of sockets by the cable, he
was a nightmare.

Anyhow his scooter has 2 chargers, 1 he lost the fuse (ordered ebay) and
the other (this one) who knows what he done. I have replaced the
batteries in the scooter and it works good and I will be selling it
locally for just above what it costs to get it all going, if I need to
buy another charger so be it but if I can keep the cost down its a
better buy for some old buddy.

So if I replace a fuse and it blows the charger I aint too bothered, I
just need to know what I am looking to replace.

and now you do.


NT

On Wed, 31 Jan 2018 23:02:29 +0000, ss wrote:

On 31/01/2018 22:30, Martin Brown wrote:
A lash up with a 3A mains fuse is worth a try but be prepared for the
magic smoke coming out or worse. You don't want it starting a fire.

I'd conduct any tests outdoors and wear eye protection. YMMV

No problem with that it will be at the end of a long extension lead out
the back garden.

As for the 3A fuse, looking at the remains of the old one would I be
correct in saying it was in the form of an upside down U shape, as I see
there are 2 points of damage, the remains of a glass fuse and then the
longish wire with just a cap on it, I presume these were connected at
one point and I basically bridge that gap with the fuse.

Yes.

And they would have looked like this:

https://www.picclickimg.com/d/l400/p...-Blow-20mm.jpg

Cheers, T i m

On 31/01/2018 23:47, T i m wrote:
Yes.

And they would have looked like this:

https://www.picclickimg.com/d/l400/p...-Blow-20mm.jpg

Cheers, T i m

Thanks Tim, I will get a couple of ebay as they will be easier to
solder on to the board.

On 31/01/2018 23:47, T i m wrote:
And they would have looked like this:

https://www.picclickimg.com/d/l400/p...-Blow-20mm.jpg

Cheers, T i m

Hopefully final question :-)

Would it be a fast blow or slow blow fuse?

ss used his keyboard to write :
Charger for a mobility scooter. One charger not working, I opened it up and
as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to solder
this part if I can find a replacement.

https://imgur.com/a/QTZ0e

From what I can see in the image, it looks like a wire ended fuse which
has exploded. That suggests a serious fault.

Also from what I can see, it looks like a fairly crude charger.
transformer, bridge, then possibly a relay switching the charge current
on and off, driven by a basic voltage across the battery sensing
circuit.

On 01/02/2018 08:14, ss wrote:
On 31/01/2018 23:47, T i m wrote:
And they would have looked like this:

https://www.picclickimg.com/d/l400/p...-Blow-20mm.jpg


Cheers, T i m

Hopefully final question :-)

Would it be a fast blow or slow blow fuse?

I expect it is into a transformer and a chunky PSU capacitor so a fast
blow might well go pop just from the inrush current on a bad day.

Be aware that fuses don't usually go bang that spectacularly unless
there is a major fault (as in dead short somewhere).

--
Regards,
Martin Brown

On 31/01/2018 20:06, Brian Gaff wrote:
I cannot see the picture, but is it a switch mode device or a good old
analogue supply?
If the latter the most common fault is the bridge rectifiers which are
commonly under specified for spikes in current etc.

If its swwitch mode then it might be possible to get a new module, but I've
seenin the past that companies have cut costs by fitting a soldered in fuse
as of course they never blow do they? :-)

Is the company that made the device still around?
Brian

The picture only shows a section of the board- 4 diodes (presumably a
bridge rectifier), and what looks like a space for a PCB fuseholder with
a soldered-in fuse in it's place that looks like it has exploded.

On 01/02/2018 08:33, Harry Bloomfield wrote:
ss used his keyboard to write :
Charger for a mobility scooter. One charger not working, I opened it
up and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

From what I can see in the image, it looks like a wire ended fuse which
has exploded. That suggests a serious fault.

Also from what I can see, it looks like a fairly crude charger.
transformer, bridge, then possibly a relay switching the charge current
on and off, driven by a basic voltage across the battery sensing circuit.

Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?

ss has brought this to us :
Could it be that if the batteries on the scooter were goosed that the charger
was trying to draw too much power and blew the fuse?

Quite possible. You might not be able to source a 3A fuse, a 3.15A will
be fine, try it without being connected to the batteries to see if it
still blows.

On Thursday, 1 February 2018 09:14:01 UTC, ss wrote:
On 01/02/2018 08:33, Harry Bloomfield wrote:
ss used his keyboard to write :
Charger for a mobility scooter. One charger not working, I opened it
up and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

From what I can see in the image, it looks like a wire ended fuse which
has exploded. That suggests a serious fault.

Also from what I can see, it looks like a fairly crude charger.
transformer, bridge, then possibly a relay switching the charge current
on and off, driven by a basic voltage across the battery sensing circuit.

Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?

very unlikely. The huge current required to do that must have come from the batteries, the charger would not be able to supply it.


NT

Chris Bartram expressed precisely :
The picture only shows a section of the board- 4 diodes (presumably a bridge
rectifier), and what looks like a space for a PCB fuseholder with a
soldered-in fuse in it's place that looks like it has exploded.

Which certainly would happen, if the batteries were connected in
reverse.

ss presented the following explanation :
As for the 3A fuse, looking at the remains of the old one would I be correct
in saying it was in the form of an upside down U shape, as I see there are 2
points of damage, the remains of a glass fuse and then the longish wire with
just a cap on it, I presume these were connected at one point and I basically
bridge that gap with the fuse.

It looks as if the wire ended fuse was mounted vertically, with the
upper wire folded over and back down to the PCB. Often they design
PCB's with component options. In this case it looks as if it might have
been designed for a fuseholder, but to save a few pennies they used a
wire ended fuse direct to the PCB.

On 01/02/2018 10:25, wrote:
Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?
very unlikely. The huge current required to do that must have come from the batteries, the charger would not be able to supply it.

Maybe I am thinking the wrong way, my thinking is saying that the
charger may have been trying to draw more power from the mains to charge
what were effectively dead batteries.

ss wrote on 01/02/2018 :
Hopefully final question :-)

Would it be a fast blow or slow blow fuse?

My guess would be a slow blow, to allow for the initial in rush surge.

On 01/02/2018 10:25, Harry Bloomfield wrote:
ss has brought this to us :
Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?

Quite possible. You might not be able to source a 3A fuse, a 3.15A will
be fine, try it without being connected to the batteries to see if it
still blows.

I have ordered a fuse from ebay, Yes I will try that Harry as it may
well be something on the scooter that is at fault although I doubt that
as the scooter was being used until the batteries failed, who knows.

The scooter itself works ok as I replaced with new batteries.

On 01/02/18 10:25, wrote:
On Thursday, 1 February 2018 09:14:01 UTC, ss wrote:
On 01/02/2018 08:33, Harry Bloomfield wrote:
ss used his keyboard to write :
Charger for a mobility scooter. One charger not working, I opened it
up and as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to
solder this part if I can find a replacement.

https://imgur.com/a/QTZ0e

From what I can see in the image, it looks like a wire ended fuse which
has exploded. That suggests a serious fault.

Also from what I can see, it looks like a fairly crude charger.
transformer, bridge, then possibly a relay switching the charge current
on and off, driven by a basic voltage across the battery sensing circuit.

Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?

very unlikely. The huge current required to do that must have come from the batteries, the charger would not be able to supply it.



Which would be why the fuse blew?

NT



--
Microsoft : the best reason to go to Linux that ever existed.

On Thursday, 1 February 2018 10:35:34 UTC, ss wrote:
On 01/02/2018 10:25, tabbypurr wrote:

Could it be that if the batteries on the scooter were goosed that the
charger was trying to draw too much power and blew the fuse?
very unlikely. The huge current required to do that must have come from the batteries, the charger would not be able to supply it.

Maybe I am thinking the wrong way, my thinking is saying that the
charger may have been trying to draw more power from the mains to charge
what were effectively dead batteries.

Any charger that blew itself to bits by gross overload when connected to a flat battery would be dangerous & illegal. I've seen many illegal & unsafe chargers, but nothing that bad.


NT

On Thursday, 1 February 2018 10:36:22 UTC, Harry Bloomfield wrote:
ss wrote on 01/02/2018 :
Hopefully final question :-)

Would it be a fast blow or slow blow fuse?

My guess would be a slow blow, to allow for the initial in rush surge.

If it's on the mains side, 3A is high enough not to need to be slow blow. If on the low side, there is no need for slow blow. Thus it will have been a cheaper F3A fuse.


NT

On Thursday, 1 February 2018 10:39:20 UTC, ss wrote:
On 01/02/2018 10:25, Harry Bloomfield wrote:
ss has brought this to us :

I have ordered a fuse from ebay, Yes I will try that Harry as it may

do you not have a 3A mains plug fuse?

well be something on the scooter that is at fault although I doubt that

that can't be the cause