Siemens WD14H421GB Washer-Dryer Doesn't Spin

On 23/05/2019 08:01, Andy Burns wrote:
Woody wrote:

most modern machines use a stepping motor which makes it much easier
to control direction and speed of rotation.

The engineer said my hotpoint washer/dryer (post indesit/ariston
takeover) uses a 3-ph motor driven by a VFD.

almost the same. Its a very moot point as to when a multipole 3 phase
motors ceases to be a 3 phase motor and becomes a stepper motor.



--
Gun Control: The law that ensures that only criminals have guns.

Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes it
much easier to control direction and speed of rotation. However because
it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to drain
as it will not continue if it thinks there is still water in the tub. As
has been suggested it could be a coin in the pump or a sock stuck in the
outer drum that is blocking the pump inlet - fingers will usually find
if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine empty
about once a month or so to remove the gunge. We find it is very
effective. Generally if there is gunge it will stink.


Interesting.

Bill


My Miele washing machine, being Germanic, lights a “hygiene� indicator if
it has done too many low temperature washes without a hot wash. My old
Bosch washer ended up getting black mould being imbedded in the door seal
which would never shift. So with my Miele I now run it occasionally at 90
degrees C with a bottle of Aldi washing machine cleaner. The machine is as
shiny and clean as the day it was purchased.

On Thu, 23 May 2019 17:55:51 +0000 (UTC) Tweed
posted:

Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes it
much easier to control direction and speed of rotation. However because
it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to drain
as it will not continue if it thinks there is still water in the tub. As
has been suggested it could be a coin in the pump or a sock stuck in the
outer drum that is blocking the pump inlet - fingers will usually find
if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine empty
about once a month or so to remove the gunge. We find it is very
effective. Generally if there is gunge it will stink.


Interesting.

Bill


My Miele washing machine, being Germanic, lights a ?hygiene? indicator if
it has done too many low temperature washes without a hot wash. My old
Bosch washer ended up getting black mould being imbedded in the door seal
which would never shift. So with my Miele I now run it occasionally at 90
degrees C with a bottle of Aldi washing machine cleaner. The machine is as
shiny and clean as the day it was purchased.

Wiping the seal and rinsing the soap drawer, especially of fabric
conditional, after every day's use pays dividends too.

My Bosch is 4 years old and sparkles for that 2 minutes of attention.

On Thu 23/05/2019 18:55, Tweed wrote:
Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes it
much easier to control direction and speed of rotation. However because
it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to drain
as it will not continue if it thinks there is still water in the tub. As
has been suggested it could be a coin in the pump or a sock stuck in the
outer drum that is blocking the pump inlet - fingers will usually find
if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine empty
about once a month or so to remove the gunge. We find it is very
effective. Generally if there is gunge it will stink.


Interesting.

Bill


My Miele washing machine, being Germanic, lights a “hygiene� indicator if
it has done too many low temperature washes without a hot wash. My old
Bosch washer ended up getting black mould being imbedded in the door seal
which would never shift. So with my Miele I now run it occasionally at 90
degrees C with a bottle of Aldi washing machine cleaner. The machine is as
shiny and clean as the day it was purchased.

The hot wash does, to some extent at least, alleviate the
'black-spots-on-the-door-seal' problem, but not completely. HG do a
mould remover which is very effective. There is also a powder product
that you use to do an empty hot wash and it not only removes the black
spots, it also shifts all that gunge that liquid washes at low temps
produce (see my earlier.) Magic stuff but I can't remember the name of
the **** stuff!

--
Woody

harrogate three at ntlworld dot com

On 23/05/2019 05:10, Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes
it much easier to control direction and speed of rotation. However
because it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to
drain as it will not continue if it thinks there is still water in the
tub. As has been suggested it could be a coin in the pump or a sock
stuck in the outer drum that is blocking the pump inlet - fingers will
usually find if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine
empty about once a month or so to remove the gunge. We find it is very
effective. Generally if there is gunge it will stink.


Interesting.

Bill

So, a bit like rural broadband delivered by overhead lines,
where the phone is never actually used. Ringing the landline
number every so often, sends the ?60 volt ringing pulse down
the line and helps to prevent cable joints going high-resistance.

On Fri 24/05/2019 15:06, Andrew wrote:
On 23/05/2019 05:10, Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes
it much easier to control direction and speed of rotation. However
because it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to
drain as it will not continue if it thinks there is still water in
the tub. As has been suggested it could be a coin in the pump or a
sock stuck in the outer drum that is blocking the pump inlet -
fingers will usually find if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine
empty about once a month or so to remove the gunge. We find it is
very effective. Generally if there is gunge it will stink.


Interesting.

Bill

So, a bit like rural broadband delivered by overhead lines,
where the phone is never actually used. Ringing the landline
number every so often, sends the ?60 volt ringing pulse down
the line and helps to prevent cable joints going high-resistance.



Usually 50V 25Hz a.c.

--
Woody

harrogate three at ntlworld dot com

In article ,
Woody wrote:
On Fri 24/05/2019 15:06, Andrew wrote:
On 23/05/2019 05:10, Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes
it much easier to control direction and speed of rotation. However
because it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to
drain as it will not continue if it thinks there is still water in
the tub. As has been suggested it could be a coin in the pump or a
sock stuck in the outer drum that is blocking the pump inlet -
fingers will usually find if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine
empty about once a month or so to remove the gunge. We find it is
very effective. Generally if there is gunge it will stink.


Interesting.

Bill

So, a bit like rural broadband delivered by overhead lines,
where the phone is never actually used. Ringing the landline
number every so often, sends the ?60 volt ringing pulse down
the line and helps to prevent cable joints going high-resistance.



Usually 50V 25Hz a.c.

no. usually 33Hz and less that 100v. The safety elf doesn't like 240v,,

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On Thu, 23 May 2019 08:52:29 +0100, The Natural Philosopher wrote:

On 23/05/2019 08:01, Andy Burns wrote:
Woody wrote:

most modern machines use a stepping motor which makes it much easier
to control direction and speed of rotation.

The engineer said my hotpoint washer/dryer (post indesit/ariston
takeover) uses a 3-ph motor driven by a VFD.

almost the same. Its a very moot point as to when a multipole 3 phase
motors ceases to be a 3 phase motor and becomes a stepper motor.

There's a very strong distinction between those two motor types. I
believe what you may have had in mind was the very fine distinction
between permanent magnet BLDC and three phase synchronous motors where
the distinction *is* very much finer.

A three phase synchronous motor (regardless of pole pair number) when
carefully designed, should ideally exhibit no 'cogging effect' as it is
manually rotated. Perfection in this regard is hard to achieve so some
cogging effect is still likely to be observed with such a test.

The endearing characteristic of a true three (or poly-phase) motor
(whether of induction or synchronous type) is the constant torque output
throughout each revolution once up to speed (no torque ripple).

Three phase motors designed to be driven directly from a 50 or 60 Hz
supply run at just the one fixed speed which is fine for most industrial
processes and those domestic applications where variable speed is not
required (fan motors or pumps).

Of course, this leaves the issue of getting them up to speed on
application of mains power which is solved by star to delta switching of
the windings in large industrial machines along with current limiting
resistors (smaller domestic sized machines forego the complexity of star
to delta switching, relying on current limiting resistors alone).

Such starter gear complexity only has to deal with the relatively
infrequent nought to 3000rpm speed changes, allowing the current limiting
resistors used to be rated for a short term, non repetitive duty cycle.

Until semiconductors became available that could cost effectively use
high frequency switching of the voltages and currents required to drive a
high voltage DC to three phase variable voltage and frequency inverter,
it hadn't been practical to use three phase motors for variable speed
applications such as domestic washing machine drum drives.

Today, such VFD control modules and associated sub HP rated three phase
multi-pole pair drum motors are becoming an ever more common feature of
the modern domestic washing machine.

Whilst even today, after a decade or more since they first started to
appear in high end white goods, they are still an expensive option.
However, they're beginning to become more commonly featured in high end
fridge freezers as ultra quiet, high efficiency surge free starting
compressor motors (which is useful for anyone looking to provide power
from a small emergency genset during a power blackout - what's not to
like about a VFD motor, other than their rather high price premium?).

Getting back to the VFD three phase motor's close cousin, the permanent
magnet (is there any other type?) BLDC motor driven by an ESC (electronic
speed controller) from a DC supply, torque delivery in this class lacks
the smoothness of a true three phase motor since only two of the three
phase windings are actually being driven at any one time by the
controller.

Obviously, this is no great detriment in their typical usage or else
they wouldn't be so widely deployed as high efficiency alternatives to
the classic DC brushed motor used in battery powered cordless drills,
screwdrivers, chainsaws and drone prop motors.

In the latter case, this allows each of the three windings to provide a
back emf zero crossing signal in turn to drive the commutation switching
circuit in the 'sensorless' ESCs used with drone propeller motors.

This 'sensorless' technique whilst fine with propeller or fan loads,
isn't suited to BLDC motors driving gross mechanical loads such as drills
and starter motors since it relies on the motor to actually be spinning
to generate the commutation sensing signal, the timing of which is
critical to the smooth and efficient operation of such motors.

To achieve the starting reliability and smooth running of a traditional
DC brushed motor, a BLDC motor's controller requires an accurate
mechanically synchronised signal independent of speed which works even
when at a standstill (startup or stalled by the load).

With the more traditional design of BLDC motor, this is achieved by the
extra complication of a trio of Hall Effect sensors, precisely aligned
for maximum efficiency during their manufacture, making them more
expensive.

However of late, AMS have produced a neat alternative solution[1] which
can trivially be retrofitted to any three phase alternator whether
permanent magnet type such as used by emergency inverter gensets or
separately excited as in an IC powered vehicle's alternator, neatly
converting them into a BLDC motor (a lightweight solution to upgrading a
pull cord only start emergency inverter genset to electric start for one
instance).

Although the BLDC motor has a 'cogging' characteristic more akin to that
of a stepper motor, the difference in this case is that it's an
undesirable side effect best minimised by design whilst in the stepper
motor case it's a desirable effect best maximised by design. Also, the
major difference between the two motor types is that stepper motors are
normally a two phase design and the BLDC motor is always a three phase
one, more akin to that of a traditional three phase AC motor.

[1] For the more curious amongst you, there's an in depth article
covering the subject of BLDC control at this web address:-

https://www.electronicproducts.com/A...l_ICs/Sensors/
Absolute_position_sensing_the_key_to_better_brushl ess_DC_motor_control.aspx

https://tinyurl.com/y2u5n9r9

HTH & HAND! :-)

--
Johnny B Good

On Fri 24/05/2019 17:43, charles wrote:
In article ,
Woody wrote:
On Fri 24/05/2019 15:06, Andrew wrote:
On 23/05/2019 05:10, Bill Wright wrote:
On 22/05/2019 15:53, Woody wrote:
For the record most modern machines use a stepping motor which makes
it much easier to control direction and speed of rotation. However
because it is doing part of the wash it is unlikely to be that at fault.

In practice the commonest fault is that the machine has failed to
drain as it will not continue if it thinks there is still water in
the tub. As has been suggested it could be a coin in the pump or a
sock stuck in the outer drum that is blocking the pump inlet -
fingers will usually find if it is.

The other question, is the OP using liquid wash at lower temps rather
than powder? Liquid can cause horrendous gunging up of the pump, the
outlet pipe of the machine, and especially the fixed pipe into the
drainage system. We have a Miele and they recommend that if you use
liquid you should do a long high temp powder wash with the machine
empty about once a month or so to remove the gunge. We find it is
very effective. Generally if there is gunge it will stink.


Interesting.

Bill

So, a bit like rural broadband delivered by overhead lines,
where the phone is never actually used. Ringing the landline
number every so often, sends the ?60 volt ringing pulse down
the line and helps to prevent cable joints going high-resistance.



Usually 50V 25Hz a.c.

no. usually 33Hz and less that 100v. The safety elf doesn't like 240v,,

Sorry Charles, wrong.

In the UK in the days of Strowger the ringing frequency was 17Hz but
when Crossbar and electronics came into the arena it went to 25Hz where
it stays to this day. Voltage is nominally 50Vac but it is quite normal
for this to be as high as 70V - indeed that is the voltage offered by
most VoIP ATA units.

--
Woody

harrogate three at ntlworld dot com

On Fri 24/05/2019 18:06, Johnny B Good wrote:
On Thu, 23 May 2019 08:52:29 +0100, The Natural Philosopher wrote:

On 23/05/2019 08:01, Andy Burns wrote:
Woody wrote:

most modern machines use a stepping motor which makes it much easier
to control direction and speed of rotation.

The engineer said my hotpoint washer/dryer (post indesit/ariston
takeover) uses a 3-ph motor driven by a VFD.

almost the same. Its a very moot point as to when a multipole 3 phase
motors ceases to be a 3 phase motor and becomes a stepper motor.

There's a very strong distinction between those two motor types. I
believe what you may have had in mind was the very fine distinction
between permanent magnet BLDC and three phase synchronous motors where
the distinction *is* very much finer.

A three phase synchronous motor (regardless of pole pair number) when
carefully designed, should ideally exhibit no 'cogging effect' as it is
manually rotated. Perfection in this regard is hard to achieve so some
cogging effect is still likely to be observed with such a test.

The endearing characteristic of a true three (or poly-phase) motor
(whether of induction or synchronous type) is the constant torque output
throughout each revolution once up to speed (no torque ripple).

Three phase motors designed to be driven directly from a 50 or 60 Hz
supply run at just the one fixed speed which is fine for most industrial
processes and those domestic applications where variable speed is not
required (fan motors or pumps).

Of course, this leaves the issue of getting them up to speed on
application of mains power which is solved by star to delta switching of
the windings in large industrial machines along with current limiting
resistors (smaller domestic sized machines forego the complexity of star
to delta switching, relying on current limiting resistors alone).

Such starter gear complexity only has to deal with the relatively
infrequent nought to 3000rpm speed changes, allowing the current limiting
resistors used to be rated for a short term, non repetitive duty cycle.

Until semiconductors became available that could cost effectively use
high frequency switching of the voltages and currents required to drive a
high voltage DC to three phase variable voltage and frequency inverter,
it hadn't been practical to use three phase motors for variable speed
applications such as domestic washing machine drum drives.

Today, such VFD control modules and associated sub HP rated three phase
multi-pole pair drum motors are becoming an ever more common feature of
the modern domestic washing machine.

Whilst even today, after a decade or more since they first started to
appear in high end white goods, they are still an expensive option.
However, they're beginning to become more commonly featured in high end
fridge freezers as ultra quiet, high efficiency surge free starting
compressor motors (which is useful for anyone looking to provide power
from a small emergency genset during a power blackout - what's not to
like about a VFD motor, other than their rather high price premium?).

Getting back to the VFD three phase motor's close cousin, the permanent
magnet (is there any other type?) BLDC motor driven by an ESC (electronic
speed controller) from a DC supply, torque delivery in this class lacks
the smoothness of a true three phase motor since only two of the three
phase windings are actually being driven at any one time by the
controller.

Obviously, this is no great detriment in their typical usage or else
they wouldn't be so widely deployed as high efficiency alternatives to
the classic DC brushed motor used in battery powered cordless drills,
screwdrivers, chainsaws and drone prop motors.

In the latter case, this allows each of the three windings to provide a
back emf zero crossing signal in turn to drive the commutation switching
circuit in the 'sensorless' ESCs used with drone propeller motors.

This 'sensorless' technique whilst fine with propeller or fan loads,
isn't suited to BLDC motors driving gross mechanical loads such as drills
and starter motors since it relies on the motor to actually be spinning
to generate the commutation sensing signal, the timing of which is
critical to the smooth and efficient operation of such motors.

To achieve the starting reliability and smooth running of a traditional
DC brushed motor, a BLDC motor's controller requires an accurate
mechanically synchronised signal independent of speed which works even
when at a standstill (startup or stalled by the load).

With the more traditional design of BLDC motor, this is achieved by the
extra complication of a trio of Hall Effect sensors, precisely aligned
for maximum efficiency during their manufacture, making them more
expensive.

However of late, AMS have produced a neat alternative solution[1] which
can trivially be retrofitted to any three phase alternator whether
permanent magnet type such as used by emergency inverter gensets or
separately excited as in an IC powered vehicle's alternator, neatly
converting them into a BLDC motor (a lightweight solution to upgrading a
pull cord only start emergency inverter genset to electric start for one
instance).

Although the BLDC motor has a 'cogging' characteristic more akin to that
of a stepper motor, the difference in this case is that it's an
undesirable side effect best minimised by design whilst in the stepper
motor case it's a desirable effect best maximised by design. Also, the
major difference between the two motor types is that stepper motors are
normally a two phase design and the BLDC motor is always a three phase
one, more akin to that of a traditional three phase AC motor.

[1] For the more curious amongst you, there's an in depth article
covering the subject of BLDC control at this web address:-

https://www.electronicproducts.com/A...l_ICs/Sensors/
Absolute_position_sensing_the_key_to_better_brushl ess_DC_motor_control.aspx

https://tinyurl.com/y2u5n9r9

HTH & HAND! :-)

Hmmm.
In that case why does the motor of our Miele washer do 15000rpm when
spinning?

--
Woody

harrogate three at ntlworld dot com