Tumble drier interference suppressor.

[Jeff Layman]

Four years ago I had to replace the interference suppressor in our then
4-years-old Beko tumble drier as it tripped the RCD when cooling down.
It's the one shown here:
<https://www.amazon.co.uk/Beko-Tumble-Suppressor-Interference-Filter/dp/B00LZWBAWO>

It's just gone again, so it seems there is a design fault. I could just
replace it, but wondered about using a different suppressor such as this
one:
<https://www.amazon.co.uk/Filter-CW4L2-20A-T-Noise-Suppressor-Terminal/dp/B089K6Z9FG>

It looks like it could do the job, as it seems to have X and Y-class
capacitors and is said to be rated at 20A. It's not drop-in, but there's
plenty of space to fit it.

Any comments?

--

Jeff

[RJH]

I had the same problem - but failure after about 10 years of the component
shown in your first link.

I gathered from google searches that an improved version - similar to that in
the 2nd link - was available. In the end I ordered one from Beko which did
indeed look similar to that 2nd one, and it was effectively drop in ISTR.
Fitted it and no problems in the 3 or 4 years since. But then I only used the
thing a few times, maybe 10, a year.

--
Cheers, Rob, Sheffield UK

[The Natural Philosopher]

Looks good to me

--
Ideas are more powerful than guns. We would not let our enemies have
guns, why should we let them have ideas?

Josef Stalin

[noth...@aolbin.com]

On 23/10/2023 15:07, Jeff Layman wrote:

You could leave it out ... the drier won't notice and I would be VERY
surprised if even the most sensitive local radio amateur noticed either.

[The Natural Philosopher]

OTOH some of your locally connected mains kit might suffer.

Example: the spark ignition on my oil boiler generally fucks the wifi
for a few seconds

--
"The great thing about Glasgow is that if there's a nuclear attack it'll
look exactly the same afterwards."

Billy Connolly

[charles]

In article <uh6b30$39fbt$1...@dont-email.me>,

The Natural Philosopher <t...@invalid.invalid> wrote:
> On 23/10/2023 17:32, noth...@aolbin.com wrote:
> > On 23/10/2023 15:07, Jeff Layman wrote:
> >> Four years ago I had to replace the interference suppressor in our
> >> then 4-years-old Beko tumble drier as it tripped the RCD when cooling
> >> down. It's the one shown here:
> >> <https://www.amazon.co.uk/Beko-Tumble-Suppressor-Interference-Filter/dp/B00LZWBAWO>
> >>
> >> It's just gone again, so it seems there is a design fault. I could
> >> just replace it, but wondered about using a different suppressor such
> >> as this one:
> >> <https://www.amazon.co.uk/Filter-CW4L2-20A-T-Noise-Suppressor-Terminal/dp/B089K6Z9FG>
> >>
> >> It looks like it could do the job, as it seems to have X and Y-class
> >> capacitors and is said to be rated at 20A. It's not drop-in, but
> >> there's plenty of space to fit it.
> >>
> >> Any comments?
> >>
> > You could leave it out ... the drier won't notice and I would be VERY
> > surprised if even the most sensitive local radio amateur noticed either.

> OTOH some of your locally connected mains kit might suffer.

> Example: the spark ignition on my oil boiler generally fucks the wifi
> for a few seconds

same heer, but it's a gas boiler. I found (probably on Amazon) a suppressor
unit with a 13~A plug and socket into which I plugged the boiler. A vast
improvement.

--
from KT24 in Surrey, England - sent from my RISC OS 4t้ฒ
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

[John Walliker]

I had a similar failure a few months ago. This was a fairly old Creda tumble
drier which would occasionally trip the RCBO it was supplied from, but only
when it was in full power mode. The suppressor was a cylindrical, wire-ended
type mounted with a metal tab and connected to the mains inlet
terminal block. It was marked
KPB 7336 X1 Y2 0.1uF + 2 x 5000pF 275V~ 25/085/21/B
There was a sticky mess around it. Maybe the leakage current increased with
temperature. I simply removed it as I couldn't easily find an identical replacement.
If I ever notice any interference problems I can always fit something similar.
It can't do much beyond a few MHz because of the inductance of the connecting wires.
John

[Harry Bloomfield Esq]

On 23/10/2023 15:07, Jeff Layman wrote:

> It looks like it could do the job, as it seems to have X and Y-class
> capacitors and is said to be rated at 20A. It's not drop-in, but there's
> plenty of space to fit it.
>
> Any comments?
>

Yep, it will be fine.

[Fredxx]

On 23/10/2023 15:07, Jeff Layman wrote:

The suppressor you show will inherent have a leakage current to earth.
It Y capacitance of 27nF suggests a small earth current of 2mA. Also at
switch-on there will be a current spike to earth.

I wouldn't have thought either could trip the RCD unless overly
sensitive or faulty.

Your second filter is more sophisticated and has a very low leakage path
to earth.

I might be tempted to run the tumble drier without the suppressor, but I
wouldn't want to rule out any other leakage path in the tumble drier
that could pose a greater danger. I'd recommend taking it apart and
giving it a very good clean.

[John Walliker]

Definitely. When I took mine apart I found damp fluff in all sorts of places
outside the main air path. It lives in a damp garage, so this is no great
surprise. I also noticed that one of the mica supports for the heating elements
was broken so I replaced the heater as well. The only problem with this
replacement was that the connectors on the replacement were slightly different
to those on the original, but that was quickly fixed with a soldering iron and some
cannibalisation.
John

[Jeff Layman]

We clean out the filter after each use, and the condenser every couple
of months. There's always a bit of wet fluff there but nothing major
which could pose a fire hazard. I'm going to get into the tumble drier
later today and have a nose around.

I've never been able to understand why the suppressor trips the RCD when
the tumble drier has finished its cycle and has started to cool down. At
that stage, I've already turned off the double-pole mains switch so that
it's only the suppressor which is connected across the mains (it's just
inside where the mains cable enters the tumble drier); the rest of the
drier is isolated by the main switch. Somehow, one of the 27nF Y2
capacitors is short-circuiting to earth.

--

Jeff

[The Natural Philosopher]

On 25/10/2023 08:28, Jeff Layman wrote:
> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.

Only have to leak a bit


--
WOKE is an acronym... Without Originality, Knowledge or Education.

[alan_m]

On 25/10/2023 08:58, The Natural Philosopher wrote:
> On 25/10/2023 08:28, Jeff Layman wrote:
>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>
> Only have to leak a bit
>
>

Suppressor terminals (or area between) getting damp during cool-down?

Possibly high humidity inside the case just after a cycle with fairly
rapid cooling of some metal parts.



--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

[Jeff Layman]

On 25/10/2023 09:28, alan_m wrote:
> On 25/10/2023 08:58, The Natural Philosopher wrote:
>> On 25/10/2023 08:28, Jeff Layman wrote:
>>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>>
>> Only have to leak a bit
>>
>>
>
> Suppressor terminals (or area between) getting damp during cool-down?
>
> Possibly high humidity inside the case just after a cycle with fairly
> rapid cooling of some metal parts.

That's a possibility, but it might be the suppressor after all.

I just took it out to find a sticky transparent fluid over part of it.
Looks like the potting or something in it is leaking. However, as it's
mounted upside-down, the fluid didn't seem to be getting on the spade
terminals.

Looks like the "non-Beko" filter will fit with a bit of fiddling, so I
think I'll try one of those.

--

Jeff

[Fredxx]

On 25/10/2023 08:58, The Natural Philosopher wrote:

> On 25/10/2023 08:28, Jeff Layman wrote:
>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>
> Only have to leak a bit

30mA @ 240V is 7W. I don't think a Y2 capacitor would last very long
with that sort of heat being generated?

Any leakage is bound to be elsewhere in the machine, or a earth-neutral
short. The earth-neutral can be elsewhere but under those faulty wiring
conditions the RCD would normally only trip under a load so not relevant
if the RCD only trips when the drier switches off.

[Custos Custodum]

On Wed, 25 Oct 2023 12:38:44 +0100, Fredxx <fre...@spam.invalid>
wrote:

>On 25/10/2023 08:58, The Natural Philosopher wrote:
>> On 25/10/2023 08:28, Jeff Layman wrote:
>>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>>
>> Only have to leak a bit
>
>30mA @ 240V is 7W. I don't think a Y2 capacitor would last very long
>with that sort of heat being generated?
>

But the current and voltage are in quadrature, shirley?

[Fredxx]

Yes, but the capacitive reactive current of a 27nF will be around 2mA.

I = V / Xc

Xc = 1 / (50 * 2 * Pi * 27nF)

Where's the other 28-30mA going? I can only assume it will be
dissipative. Either way I would be opening up the tubule drier and
giving a good clean and once-over.

[Animal]

On Monday, 23 October 2023 at 15:07:28 UTC+1, Jeff Layman wrote:
> Four years ago I had to replace the interference suppressor in our then
> 4-years-old Beko tumble drier as it tripped the RCD when cooling down.
> It's the one shown here:
> <https://www.amazon.co.uk/Beko-Tumble-Suppressor-Interference-Filter/dp/B00LZWBAWO>

3 caps + resistor. £18 is steep

> It's just gone again, so it seems there is a design fault. I could just
> replace it, but wondered about using a different suppressor such as this
> one:
> <https://www.amazon.co.uk/Filter-CW4L2-20A-T-Noise-Suppressor-Terminal/dp/B089K6Z9FG>
>
> It looks like it could do the job, as it seems to have X and Y-class
> capacitors and is said to be rated at 20A. It's not drop-in, but there's
> plenty of space to fit it.
>
> Any comments?

far more effective at suppressig interference. Do you actually need to suppress any interference? In many cases such filtering isn't necessary.

[alan_m]

On 25/10/2023 18:11, Animal wrote:

>
> far more effective at suppressig interference. Do you actually need to suppress any interference? In many cases such filtering isn't necessary.

If the manufacturer could have saved a few pennies by not fitting
suppression they would have done so :)

[Animal]

On Wednesday, 25 October 2023 at 18:15:26 UTC+1, alan_m wrote:
> On 25/10/2023 18:11, Animal wrote:
>
> >
> > far more effective at suppressig interference. Do you actually need to suppress any interference? In many cases such filtering isn't necessary.
> If the manufacturer could have saved a few pennies by not fitting
> suppression they would have done so :)

Mfrs are legally required to fit it. Sometimes it's functionally semi-necessary, more often not.

[The Natural Philosopher]

On 25/10/2023 10:38, Jeff Layman wrote:
> On 25/10/2023 09:28, alan_m wrote:
>> On 25/10/2023 08:58, The Natural Philosopher wrote:
>>> On 25/10/2023 08:28, Jeff Layman wrote:
>>>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>>>
>>> Only have to leak a bit
>>>
>>>
>>
>> Suppressor terminals (or area between) getting damp during cool-down?
>>
>> Possibly high humidity inside the case just after a cycle with fairly
>> rapid cooling of some metal parts.
>
> That's a possibility, but it might be the suppressor after all.
>
> I just took it out to find a sticky transparent fluid over part of it.
> Looks like the potting or something in it is leaking. However, as it's
> mounted upside-down, the fluid didn't seem to be getting on the spade
> terminals.
>

Classic cheap mains capacitor leaking.

> Looks like the "non-Beko" filter will fit with a bit of fiddling, so I
> think I'll try one of those.
>

Yup.

I think that will fix your problems perfectly

--
How fortunate for governments that the people they administer don't think.

Adolf Hitler

[The Natural Philosopher]

On 25/10/2023 14:11, Custos Custodum wrote:

Of course.

Fredxx is displaying his ignorance again

[The Natural Philosopher]

On 25/10/2023 18:15, alan_m wrote:
> On 25/10/2023 18:11, Animal wrote:
>
>>
>> far more effective  at suppressig interference. Do you actually need
>> to suppress any  interference? In many cases such filtering isn't
>> necessary.
>
> If the manufacturer could have saved a few pennies by not fitting
> suppression they would have done so :)
>

Well, that is in fact a moot point.

brushed motors generate sparks, and a good filter keeps that out of the
mains so that the electrical certification is *guaranteed*.

No manufacturer wants to faff around measuring a thousand units to see
if they all pass when a cheap POS chinesium filter module *guarantees*
that they will...

[Fredxx]

On 25/10/2023 18:31, The Natural Philosopher wrote:
> On 25/10/2023 14:11, Custos Custodum wrote:
>> On Wed, 25 Oct 2023 12:38:44 +0100, Fredxx <fre...@spam.invalid>
>> wrote:
>>
>>> On 25/10/2023 08:58, The Natural Philosopher wrote:
>>>> On 25/10/2023 08:28, Jeff Layman wrote:
>>>>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>>>>
>>>> Only have to leak a bit
>>>
>>> 30mA @ 240V is 7W. I don't think a Y2 capacitor would last very long
>>> with that sort of heat being generated?
>>>
>> But the current and voltage are in quadrature, shirley?
>>
> Of course.
>
> Fredxx is displaying his ignorance again

Do explain how? I know you can't when it comes to anything engineering
or technical.

[Fredxx]

On 25/10/2023 18:35, The Natural Philosopher wrote:
> On 25/10/2023 18:15, alan_m wrote:
>> On 25/10/2023 18:11, Animal wrote:
>>
>>>
>>> far more effective  at suppressig interference. Do you actually need
>>> to suppress any  interference? In many cases such filtering isn't
>>> necessary.
>>
>> If the manufacturer could have saved a few pennies by not fitting
>> suppression they would have done so :)
>>
> Well, that is in fact a moot point.
>
> brushed motors generate sparks, and a good filter keeps that out of the
> mains so that the electrical certification is *guaranteed*.

When was the last time you saw a brushed motor in a tumble drier? It
just goes to show that you don't have a clue.

[nib]

If it has an induction motor, heating by resistors with no current
control and a mechanical timer with a synchronous motor, it probably
won't create any interference while running; but it might still create
switching spikes when switching on or off which the manufacturer would
have to control.

But then there wouldn't in practice be any issue with omitting the filter?

nib

[RJH]

On 25 Oct 2023 at 10:38:12 BST, Jeff Layman wrote:

> On 25/10/2023 09:28, alan_m wrote:
>> On 25/10/2023 08:58, The Natural Philosopher wrote:
>>> On 25/10/2023 08:28, Jeff Layman wrote:
>>>> Somehow, one of the 27nF Y2 capacitors is short-circuiting to earth.
>>>
>>> Only have to leak a bit
>>>
>>>
>>
>> Suppressor terminals (or area between) getting damp during cool-down?
>>
>> Possibly high humidity inside the case just after a cycle with fairly
>> rapid cooling of some metal parts.
>
> That's a possibility, but it might be the suppressor after all.
>
> I just took it out to find a sticky transparent fluid over part of it.
> Looks like the potting or something in it is leaking. However, as it's
> mounted upside-down, the fluid didn't seem to be getting on the spade
> terminals.
>

Yep, same here.

> Looks like the "non-Beko" filter will fit with a bit of fiddling, so I
> think I'll try one of those.

As mentioned up thread, the ones Beko now supply seem to have been updated -
that what I fitted anyway, and the price was about the same.

[Jack Harry Teesdale]

On 23/10/2023 15:07, Jeff Layman wrote:
> Four years ago I had to replace the interference suppressor in our then
> 4-years-old Beko tumble drier as it tripped the RCD when cooling down.
> It's the one shown here:
> <https://www.amazon.co.uk/Beko-Tumble-Suppressor-Interference-Filter/dp/B00LZWBAWO>
>

> It's just gone again, so it seems there is a design fault. I could just
> replace it, but wondered about using a different suppressor such as this
> one:
> <https://www.amazon.co.uk/Filter-CW4L2-20A-T-Noise-Suppressor-Terminal/dp/B089K6Z9FG>
>
> It looks like it could do the job, as it seems to have X and Y-class
> capacitors and is said to be rated at 20A. It's not drop-in, but there's
> plenty of space to fit it.
>
> Any comments?
>

Why bother replacing it, the T/D will work just as well without and it
won't trip.

[noth...@aolbin.com]

On 25/10/2023 18:15, alan_m wrote:

> On 25/10/2023 18:11, Animal wrote:
>
>>
>> far more effective  at suppressig interference. Do you actually need
>> to suppress any  interference? In many cases such filtering isn't
>> necessary.
>
> If the manufacturer could have saved a few pennies by not fitting
> suppression they would have done so :)
>
>

Manufacturers have to demonstrate that equipment meets the conducted and
radiated emission specifications (amongst other things) in order to be
able to CE mark their products and "place them on the market". You
removing the filter from one device is not going to affect anything.

[Paul]

But you'd agree though, that the implementation in this case, is just stupid.

That filter is not fitted because of some motor issue.

That filter is fitted, because the machine has an SMPS providing
regulated DC power to some stinking processor. And undoubtedly,
the machine has unfiltered digital wiring running all over the
place, an emissions-guy worst nightmare. That means the box is
filled to the scuppers, with emissions.

The filter need only have gone in the SMPS path, and the filter
then needs only a tiny current rating. The filter does not
need to be filtering any electric fire current or any motor currents.
They could put passthru filter caps, on the wiring exiting the
controller board.

There might still be some coupled interference currents, between
the SMPS area, and AC wiring for the non-digital parts. Perhaps
an emissions expert could tell us what to use for that. I don't
know what a large ferrite bead will do, when heavy AC currents are present.
I hope it would not react, but I'm not sure about that.

There are plenty of power tools and other things we use daily,
which have no broadband filter networks on input. Those filters
seem to be reserved for SMPS-equipped products.

Paul

[noth...@aolbin.com]

No, I would not agree. If a filter is going to stand a chance of being
effective it needs to be on the machine input, otherwise the wiring
between the input and the filter receives radiated interference from
anything that is radiating (SMPS, motor controller, whatever) inside the
machine case and transmits it outside the case. This is why filters
should always be at the point of entry. I've now hinted at one of my
former lives ;-)

[John Walliker]

That doesn't explain why my tumble drier had a filter (now removed after
the sticky liquid came out).
It has a mechanical timer driven by a small synchronous motor and the
main motor is also synchronous. There is no cpu, no display or anything
likely to generate RF. The only thing that might need suppression is
switching spikes.
John



> Paul