Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?
--
Tim Lamb

Our Siemens (also made by Bosch) did the same replacing the brushes fixed it. If you have a badly scored commutator you may find you go through brushes rapidly but for the the price they are and the 20 mins to fix it is worth a punt.

Richard

In message ,
Tricky Dicky writes
Our Siemens (also made by Bosch) did the same replacing the brushes
fixed it. If you have a badly scored commutator you may find you go
through brushes rapidly but for the the price they are and the 20 mins
to fix it is worth a punt.

Bosch set (30ukp) on order. I'll give the comm. a tidy up before
re-fitting.

Ta.

--
Tim Lamb

On Sat, 25 Mar 2017 10:44:04 +0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

AFAIK the flexible braided wire should be short enough not to allow
that to happen.

Treat it to some new brushes and if it continues to trip the RCD strip
it down, inspect, and clean the carbon deposits off the commutator,
brush carriers etc.


--

Graham.
%Profound_observation%

On Saturday, 25 March 2017 12:31:46 UTC, Graham. wrote:
On Sat, 25 Mar 2017 10:44:04 +0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

AFAIK the flexible braided wire should be short enough not to allow
that to happen.

Treat it to some new brushes and if it continues to trip the RCD strip
it down, inspect, and clean the carbon deposits off the commutator,
brush carriers etc.

One needs to be thorough with the carbon, which can be slow. Last time I resurfaced a WM commutator by running it on 12v (IIRC) and using a file. Sometimes insulation trouble can be sorted out by mounting a motor on insulating mountings.


NT

On 25/03/17 10:44, Tim Lamb wrote:
Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

bought a recon motor some year s back for around 75 exchange when mine
did this.

wasn't brushes. Was a short from a winding to earth on the armature.

--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

In message , The Natural Philosopher
writes
On 25/03/17 10:44, Tim Lamb wrote:
Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

bought a recon motor some year s back for around 75 exchange when mine
did this.

wasn't brushes. Was a short from a winding to earth on the armature.

75 sounds better:-)

These brushes are badly worn. I wonder if the copper in contact with the
com. leads to excessive arcing.

I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


--
Tim Lamb

On 25/03/17 18:51, Tim Lamb wrote:
In message , The Natural Philosopher
writes
On 25/03/17 10:44, Tim Lamb wrote:
Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

bought a recon motor some year s back for around 75 exchange when mine
did this.

wasn't brushes. Was a short from a winding to earth on the armature.

75 sounds better:-)

These brushes are badly worn. I wonder if the copper in contact with the
com. leads to excessive arcing.

I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings from
the commutator segments. Its rare for arcing to blow an RCD unless you
have **** loads of electronics (RFI caps) between live and earth in the
house and a rather high impedance supply.

--
€œBut what a weak barrier is truth when it stands in the way of an
hypothesis!€�

Mary Wollstonecraft

In message , The Natural Philosopher
writes
On 25/03/17 18:51, Tim Lamb wrote:
bought a recon motor some year s back for around 75 exchange when mine
did this.

wasn't brushes. Was a short from a winding to earth on the armature.

75 sounds better:-)

These brushes are badly worn. I wonder if the copper in contact with the
com. leads to excessive arcing.

I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings
from the commutator segments. Its rare for arcing to blow an RCD unless
you have **** loads of electronics (RFI caps) between live and earth in
the house and a rather high impedance supply.

On the desk beside me. I don't have access to a Megger but I can try my
multimeter.

I don't think there is anything high impedance about an agricultural 3
ph. supply and I'm not aware of any line/earth shunts other than what is
hidden in our various bits of domestic electronics.


--
Tim Lamb

In message , The Natural Philosopher
writes
On 25/03/17 18:51, Tim Lamb wrote:
I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings
from the commutator segments. Its rare for arcing to blow an RCD unless
you have **** loads of electronics (RFI caps) between live and earth in
the house and a rather high impedance supply.

Open circuit on 20 meg range between frame and all comm segments.

Fair bit of carbon dust came out with the compressed air.


--
Tim Lamb

On Sat, 25 Mar 2017 10:44:04 -0000, Tim Lamb wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

Remove the RCD, they are pansies and trip for anything.

--
The success of the "Wonder Bra" for under-endowed women has encouraged the designers to come out with a bra for over-endowed women.
It's called the "Sheep Dog Bra"- it rounds them up and points them in the right direction.

"James Wilkinson Sword" wrote in message
news
On Sat, 25 Mar 2017 10:44:04 -0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

Remove the RCD, they are pansies and trip for anything.

Are you only capable of typing ********?

"James Wilkinson Sword" wrote in message
news
On Sat, 25 Mar 2017 10:44:04 -0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

Remove the RCD, they are pansies and trip for anything.

**** off to bed old son, tomorrow will be an hour later.
God knows you need a rest.

I was going to say, this sounds like either a very badly designed motor or
some malfunction has caused the scoring. I seem to recall mentioning this
once before on here when somebody found that the brush replacement still
intermittently gave error codes. Back in the day when I had a machine made
by Service, this exact same problem is what took it down. it also had
started to get dry joint issues all over the place and I thought getting
that all fixed would make it last, but it lasted three months till it
spluttered went bang and blew the fuses. Comutator basically knackered.

Such is life.
Brian

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

Blind user, so no pictures please!
"Graham." wrote in message
...
On Sat, 25 Mar 2017 10:44:04 +0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

AFAIK the flexible braided wire should be short enough not to allow
that to happen.

Treat it to some new brushes and if it continues to trip the RCD strip
it down, inspect, and clean the carbon deposits off the commutator,
brush carriers etc.


--

Graham.
%Profound_observation%

I'm not sure who mentioned it, but on some motors the comutator is
basically a pcb mounted on the back and the segments are etched into it,
whith brushes pushing against it. These el cheapo motors seem to fail a
lot. Often found in things like shredders etc.
Brian

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

Blind user, so no pictures please!
"Tim Lamb" wrote in message
...
In message , The Natural Philosopher
writes
On 25/03/17 18:51, Tim Lamb wrote:
I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings from
the commutator segments. Its rare for arcing to blow an RCD unless you
have **** loads of electronics (RFI caps) between live and earth in the
house and a rather high impedance supply.

Open circuit on 20 meg range between frame and all comm segments.

Fair bit of carbon dust came out with the compressed air.


--
Tim Lamb

Why not fit a cut off nail in the fuse holder while he is about it. Should
make a nice fire.
Brian

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

Blind user, so no pictures please!
"bm" wrote in message
web.com...

"James Wilkinson Sword" wrote in message
news
On Sat, 25 Mar 2017 10:44:04 -0000, Tim Lamb
wrote:

Bosch drive motor failure on spin function. Failed to reach full speed
and then tripped out the house RCD.

Google seems to imply this is terminal for the motor. On examination the
carbon brushes have worn to the point where the copper inserts have
marked the commutator.

Set of brushes are cheap enough but replacing the motor at 175-200ukp
seems poor economics.

Any experience?

Remove the RCD, they are pansies and trip for anything.

**** off to bed old son, tomorrow will be an hour later.
God knows you need a rest.

In message , Brian Gaff
writes
I was going to say, this sounds like either a very badly designed motor or
some malfunction has caused the scoring. I seem to recall mentioning this
once before on here when somebody found that the brush replacement still
intermittently gave error codes. Back in the day when I had a machine made
by Service, this exact same problem is what took it down. it also had
started to get dry joint issues all over the place and I thought getting
that all fixed would make it last, but it lasted three months till it
spluttered went bang and blew the fuses. Comutator basically knackered.

I suppose a washing machine is not monitored in the way a vacuum cleaner
or electric drill might be: allowing deterioration beyond that
anticipated by the motor design.

These particular brushes are able to travel and wear right down to the
point where the flexible conductor is fused to the carbon.

I am hopeful that the 30mA trip has protected the motor from serious
damage. We'll see:-)

--
Tim Lamb

On 25/03/17 21:18, Tim Lamb wrote:
In message , The Natural Philosopher
writes
On 25/03/17 18:51, Tim Lamb wrote:
bought a recon motor some year s back for around 75 exchange when mine
did this.

wasn't brushes. Was a short from a winding to earth on the armature.

75 sounds better:-)

These brushes are badly worn. I wonder if the copper in contact with the
com. leads to excessive arcing.

I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings
from the commutator segments. Its rare for arcing to blow an RCD
unless you have **** loads of electronics (RFI caps) between live and
earth in the house and a rather high impedance supply.

On the desk beside me. I don't have access to a Megger but I can try my
multimeter.

oh, mine showed about 3k with a simple multimeter. I disasembled the
whole motor and left it that way when swapped for a rewound
one....'well saves us the job of doing it mate' ... :-)


I don't think there is anything high impedance about an agricultural 3
ph. supply and I'm not aware of any line/earth shunts other than what is
hidden in our various bits of domestic electronics.

In which case I suspect you have an earth leak.







--
"When one man dies it's a tragedy. When thousands die it's statistics."

Josef Stalin

On 25/03/17 21:52, Tim Lamb wrote:
In message , The Natural Philosopher
writes
On 25/03/17 18:51, Tim Lamb wrote:
I've given the com a clean up with emery cloth and raked out the
segments. Thorough blow through with compressed air and I'll see what
new brushes achieve.


if you have it out check resistance to the frame/armature stampings
from the commutator segments. Its rare for arcing to blow an RCD
unless you have **** loads of electronics (RFI caps) between live and
earth in the house and a rather high impedance supply.

Open circuit on 20 meg range between frame and all comm segments.

field coils as well? But that's looking like good news...


Fair bit of carbon dust came out with the compressed air.




--
"When a true genius appears in the world, you may know him by this sign,
that the dunces are all in confederacy against him."

Jonathan Swift.

On Sat, 25 Mar 2017 21:52:42 +0000, Tim Lamb
wrote:

snip

Fair bit of carbon dust came out with the compressed air.


That was what fixed the RCD tripping issue for me on our AEG Lavamat.

It would (suddenly started to) trip instantly at power on but not with
the motor disconnected.

I was very surprised to see how much carbon dust came out of it.

Cheers, T i m

In message , T i m
writes
On Sat, 25 Mar 2017 21:52:42 +0000, Tim Lamb
wrote:

snip

Fair bit of carbon dust came out with the compressed air.


That was what fixed the RCD tripping issue for me on our AEG Lavamat.

It would (suddenly started to) trip instantly at power on but not with
the motor disconnected.

I was very surprised to see how much carbon dust came out of it.

Sadly there seems a bit more to this than new brushes and a blow
through.

Reassembled last night but motor not being energised. Yes I did put the
brushes in the correct way and am reasonably confident that the
connections were properly re-made.

Oh well. There is a back up m/c in the *West wing* and washing lady says
if I want clean smalls I'll need to do a swap.

Test access is from underneath the m/c so difficult to check in normal
operate mode.

Thanks to all who contributed.
--
Tim Lamb

On Wed, 29 Mar 2017 09:15:26 +0100, Tim Lamb
wrote:

In message , T i m
writes
On Sat, 25 Mar 2017 21:52:42 +0000, Tim Lamb
wrote:

snip

Fair bit of carbon dust came out with the compressed air.


That was what fixed the RCD tripping issue for me on our AEG Lavamat.

It would (suddenly started to) trip instantly at power on but not with
the motor disconnected.

I was very surprised to see how much carbon dust came out of it.

Sadly there seems a bit more to this than new brushes and a blow
through.

Reassembled last night but motor not being energised. Yes I did put the
brushes in the correct way and am reasonably confident that the
connections were properly re-made.

I'm sure they were ... so I wonder if as the brushes failed it took
out something else?

Oh well. There is a back up m/c in the *West wing* and washing lady says
if I want clean smalls I'll need to do a swap.

;-)

Test access is from underneath the m/c so difficult to check in normal
operate mode

Normally the tops come off these things by removing a couple of screws
at the back or there is also / often a back panel you can remove
(often allowing you to get to the belt / drive ring / bearings but
little else)?

Mum still has a very old washing machine (Hotpoint?) I can remember
brazing a motor bracket back on when I feel was in my 20's (now 60)
and a very much younger Whirlpool sitting beside it that did belong to
her granddaughter but requiring new bearings (that I will change when
I getroundtuit). ;-)

If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?

Cheers, T i m

On Wednesday, 29 March 2017 10:03:15 UTC+1, T i m wrote:
On Wed, 29 Mar 2017 09:15:26 +0100, Tim Lamb
wrote:

In message , T i m
writes
On Sat, 25 Mar 2017 21:52:42 +0000, Tim Lamb
wrote:

snip

Fair bit of carbon dust came out with the compressed air.


That was what fixed the RCD tripping issue for me on our AEG Lavamat.

It would (suddenly started to) trip instantly at power on but not with
the motor disconnected.

I was very surprised to see how much carbon dust came out of it.

Sadly there seems a bit more to this than new brushes and a blow
through.

Reassembled last night but motor not being energised. Yes I did put the
brushes in the correct way and am reasonably confident that the
connections were properly re-made.

I'm sure they were ... so I wonder if as the brushes failed it took
out something else?

Oh well. There is a back up m/c in the *West wing* and washing lady says
if I want clean smalls I'll need to do a swap.

;-)

Test access is from underneath the m/c so difficult to check in normal
operate mode

Normally the tops come off these things by removing a couple of screws
at the back or there is also / often a back panel you can remove
(often allowing you to get to the belt / drive ring / bearings but
little else)?

Mum still has a very old washing machine (Hotpoint?) I can remember
brazing a motor bracket back on when I feel was in my 20's (now 60)
and a very much younger Whirlpool sitting beside it that did belong to
her granddaughter but requiring new bearings (that I will change when
I getroundtuit). ;-)

If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?

Cheers, T i m

Triac would be a prime suspect.


NT

On Wed, 29 Mar 2017 03:55:09 -0700, tabbypurr wrote:

snip

If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?


Triac would be a prime suspect.

Not so easy to spot or replace as a fuse to the non electronics tech
though. ;-(

Ok, it could be easy to spot if it's blown to bits but then not so easy
to identify without the bits. ;-)

Cheers, T i m

In message , T i m
writes
Sadly there seems a bit more to this than new brushes and a blow
through.

Reassembled last night but motor not being energised. Yes I did put the
brushes in the correct way and am reasonably confident that the
connections were properly re-made.

I'm sure they were ... so I wonder if as the brushes failed it took
out something else?

All the controls/electronics are tucked away behind impenetrable
plastic. No doubt a service engineer would know how to proceed but I'll
dump it in a barn while I get on with the house.

--
Tim Lamb

In message ,
writes
Oh well. There is a back up m/c in the *West wing* and washing lady says
if I want clean smalls I'll need to do a swap.
snippage
If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?

Cheers, T i m

Triac would be a prime suspect.

Nothing visibly accessible.

Job for another day!

--
Tim Lamb

In message , T i m
writes
On Wed, 29 Mar 2017 03:55:09 -0700, tabbypurr wrote:

snip

If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?


Triac would be a prime suspect.

Not so easy to spot or replace as a fuse to the non electronics tech
though. ;-(

Ok, it could be easy to spot if it's blown to bits but then not so easy
to identify without the bits. ;-)

Hmm.. I was switching mains AC with back to back thyristors before
triacs were invented:-)

Nevertheless, you are probably correct:-)

--
Tim Lamb

On Wed, 29 Mar 2017 21:26:28 +0100, Tim Lamb
wrote:

In message , T i m
writes
On Wed, 29 Mar 2017 03:55:09 -0700, tabbypurr wrote:

snip

If you get any time and can see any of the electronics you might find
something as simple as an on-board fuse or some such?


Triac would be a prime suspect.

Not so easy to spot or replace as a fuse to the non electronics tech
though. ;-(

Ok, it could be easy to spot if it's blown to bits but then not so easy
to identify without the bits. ;-)

Hmm.. I was switching mains AC with back to back thyristors before
triacs were invented:-)

No slur or deformation intended Tim. ;-)

Nevertheless, you are probably correct:-)

Whilst anyone who 'knows their stuff' could probably work out the type
and rough specification for some unknown device, it's all so much
easier with the circuit diagram and component list. However, given
that most machines are run by a microprocessor these days, a circuit
diagram often consists of a black square with a few discrete
components around it. ;-(

I soldered a power feed wire back onto a PCB for someone today ...
it's been a long time since those sort of repairs were everyday. ;-)

Cheers, T i m