Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked here http://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

Unfortunately, I don't live somewhere I can just wander into a Maplin,
and Googling doesn't help, so any help appreciated. Thanks



The motor is a HongYang HRS-550S-18V

On Mon, 18 May 2009 13:01:26 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked here http://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":
http://www.datasheetarchive.com/pdf-...DSA-432531.pdf

For other possibilities, check page 301 and onwards of this NEC
selection guide:
http://www.datasheetarchive.com/pdf-...DSA-317291.pdf

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

On 18 May, 21:28, Franc Zabkar wrote:
On Mon, 18 May 2009 13:01:26 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked herehttp://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":http://www.datasheetarchive.com/pdf-...ts-22/DSA-4325...

For other possibilities, check page 301 and onwards of this NEC
selection guide:http://www.datasheetarchive.com/pdf-...ts-16/DSA-3172...

Wow, Franc, I am very impressed! OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

But you have given me a very good start. I wish I knew as much about
electronics.

On Mon, 18 May 2009 13:46:36 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

On 18 May, 21:28, Franc Zabkar wrote:

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":http://www.datasheetarchive.com/pdf-...ts-22/DSA-4325...

For other possibilities, check page 301 and onwards of this NEC
selection guide:http://www.datasheetarchive.com/pdf-...ts-16/DSA-3172...

OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

In your part of the world you should have a huge choice of equivalent
MOSFETs by ST Microelectronics, for example. Have a look at Farnell's
range, or RS Components.

BTW, you should check your motor before proceeding. It could be that
the brushes have worn down, or that carbon dust has shorted the
commutator segments, or that the motor windings have shorted.

I would remove the MOSFET and link its drain and source pins with a
piece of wire. This should get the drill operating at full speed. If
all is not OK, then it probably won't be worth repairing.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

In article
,
lardconcepts wrote:
Wow, Franc, I am very impressed! OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

Maplin, sadly, are pretty useless for components these days. Try RS, CPC,
Farnell, Rapid etc. All sell retail by credit card.

--
*Never put off until tomorrow what you can avoid altogether *

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

"lardconcepts" wrote in message
...
On 18 May, 21:28, Franc Zabkar wrote:
On Mon, 18 May 2009 13:01:26 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked herehttp://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":http://www.datasheetarchive.com/pdf-...ts-22/DSA-4325...

For other possibilities, check page 301 and onwards of this NEC
selection
guide:http://www.datasheetarchive.com/pdf-...ts-16/DSA-3172...

Wow, Franc, I am very impressed! OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

But you have given me a very good start. I wish I knew as much about
electronics.



If you want to learn about electronics, don't ever go to Maplin. You will
be told and sold a load of rubbish.

Here's somewhere else you can try if Farnell, RS, CPC etc are tricky with
one off small quantities:

http://www.cricklewoodelectronics.co...ewood/home.php



Gareth.

"Gareth Magennis" wrote in message
...

"lardconcepts" wrote in message
...
On 18 May, 21:28, Franc Zabkar wrote:
On Mon, 18 May 2009 13:01:26 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked herehttp://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":http://www.datasheetarchive.com/pdf-...ts-22/DSA-4325...

For other possibilities, check page 301 and onwards of this NEC
selection
guide:http://www.datasheetarchive.com/pdf-...ts-16/DSA-3172...

Wow, Franc, I am very impressed! OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

But you have given me a very good start. I wish I knew as much about
electronics.



If you want to learn about electronics, don't ever go to Maplin. You will
be told and sold a load of rubbish.

Here's somewhere else you can try if Farnell, RS, CPC etc are tricky with
one off small quantities:

http://www.cricklewoodelectronics.co...ewood/home.php



Gareth.


How do you get on with Cricklewood these days, Gareth ? I used to use them a
lot, but since they became part of that bigger group, I seem to have had
endless problems with items not being in stock - although you don't get to
know it until the delivery is missing that item - and then having to wait
sometimes a couple of weeks or more, until they can get it. A couple of
times, that caused me embarrassment with a customer, when I had told them
when their repair would be ready, based on having ordered a part from them,
only for it not to turn up, so recently, I have stopped ordering from them.

Arfa

"Arfa Daily" wrote in message
...

"Gareth Magennis" wrote in message
...

"lardconcepts" wrote in message
...
On 18 May, 21:28, Franc Zabkar wrote:
On Mon, 18 May 2009 13:01:26 -0700 (PDT), lardconcepts
put finger to keyboard and composed:

Spear and Jackson Cordless Drill model SJ-CD18KUK

Worked fine for years, mechanically sound. Now after a short time of
use, there's a puff of smoke and it slows right down. Upon opening up,
I see this smoke is pouring from the centre of a 3-legged regulator
device on a heatsink.

I have looked herehttp://www.maplin.co.uk/Search.aspx?menuno=12489
but can't find anything with similar numbers. The markings are
NEC
K2 ??4
82M

The ?? are two numbers I can't see, as that's where the burnt hole is!

I suspect it is a 2SK2??4 MOSFET which is being switched in PWM mode
to control the speed of the motor.

One possible suspect is a 2SK2984 20A 30V "SWITCHING N-CHANNEL POWER
MOS FET INDUSTRIAL USE ... designed for high current switching
application":http://www.datasheetarchive.com/pdf-...ts-22/DSA-4325...

For other possibilities, check page 301 and onwards of this NEC
selection
guide:http://www.datasheetarchive.com/pdf-...ts-16/DSA-3172...

Wow, Franc, I am very impressed! OK, sadly it seems that I might have
my work cut out finding this chip. Certainly not Maplin that sells it,
or in fact any of those chips.

But you have given me a very good start. I wish I knew as much about
electronics.



If you want to learn about electronics, don't ever go to Maplin. You
will be told and sold a load of rubbish.

Here's somewhere else you can try if Farnell, RS, CPC etc are tricky with
one off small quantities:

http://www.cricklewoodelectronics.co...ewood/home.php



Gareth.


How do you get on with Cricklewood these days, Gareth ? I used to use them
a lot, but since they became part of that bigger group, I seem to have had
endless problems with items not being in stock - although you don't get to
know it until the delivery is missing that item - and then having to wait
sometimes a couple of weeks or more, until they can get it. A couple of
times, that caused me embarrassment with a customer, when I had told them
when their repair would be ready, based on having ordered a part from
them, only for it not to turn up, so recently, I have stopped ordering
from them.

Arfa



Well funny you should say that cos up til now they have been fine. Haven't
used them for a couple of months or so now, but I Internetted an order
yesterday for some Power transistors and a hard to find driver - this
morning I received the power transistors but not the now even harder to find
driver And no explanation either, just that missing line highlighted
in luminous green.

I wasn't aware they had been taken over, perhaps this is the end of what was
a very useful company to know (I could usually find all the odd
transistors/old DRAMs etc I ever wanted)


Gareth.

If you want to learn about electronics, don't ever go to Maplin. You
will be told and sold a load of rubbish.

Here's somewhere else you can try if Farnell, RS, CPC etc are tricky
with one off small quantities:

http://www.cricklewoodelectronics.co...ewood/home.php



Gareth.


How do you get on with Cricklewood these days, Gareth ? I used to use
them a lot, but since they became part of that bigger group, I seem to
have had endless problems with items not being in stock - although you
don't get to know it until the delivery is missing that item - and then
having to wait sometimes a couple of weeks or more, until they can get
it. A couple of times, that caused me embarrassment with a customer, when
I had told them when their repair would be ready, based on having ordered
a part from them, only for it not to turn up, so recently, I have stopped
ordering from them.

Arfa



Well funny you should say that cos up til now they have been fine.
Haven't used them for a couple of months or so now, but I Internetted an
order yesterday for some Power transistors and a hard to find driver -
this morning I received the power transistors but not the now even harder
to find driver And no explanation either, just that missing line
highlighted in luminous green.

I wasn't aware they had been taken over, perhaps this is the end of what
was a very useful company to know (I could usually find all the odd
transistors/old DRAMs etc I ever wanted)


Gareth.


To be honest, I am not absolutely certain that Cricklewood have been taken
over. The work that I do mostly at the moment, calls for components from the
likes of Farnell and RS. It was a colleague who told me that Cricklewood
were no longer owned by the original people, when I mentioned the 'short'
deliveries I had received a couple of times.

Another 'small' company that used to be very good, were Grandata, but they
have definitely been taken over by some larger group, who seem to have
rationalised the stock. I no longer use them, as it had reached the point
that every time I rang them to check a stock position on an item, it came
back as nil.

For 'oddball' chips, including some of the esoteric types used on SMPS, you
might try Dalbani / Nikko

www.dalbani.co.uk

Again, their deliveries can be a bit variable, but they do carry a lot of
less mainstream parts.

Arfa

On 19 May, 16:40, "Gareth Magennis"
wrote:

Here's somewhere else you can try if Farnell, RS, CPC etc are tricky with
one off small quantities:

http://www.cricklewoodelectronics.co...ewood/home.php

Thanks for the suggestion - I sent them a close-up of the burnt
controller and motor, and they suggested it might be a 2SK2134 @ £1.50

Was slightly disappointed to find that 67p of stamp and envelope is
charged at £3 making a total of £5.18 inc, and normally I'd have
shopped around (ie: vintage-parts.com would have been £3.15 total) BUT
I was happy to pay the extra £2 as a service for the help.

Unfortunately, I guess it wasn't the right part, as I DO have a
working drill again, but it's got two speeds now - stop and go!

So, semi-result, and I've learnt a bit along the way, so thanks for
everyone's help!