Fault mode with Sealey Pillar drill electrics?

[jkn]

Hi All
I have a Sealey Pillar Drill - perhaps half a step up from the Aldi/Lidl/MachineMart basic pillar drills.

It has always worked fine, but today it fails to start when I press the green
button ;-(. Mains supply is known good. No noises of any sort.

I am not going to get chance to look at it for a while, but I am guessing
that the most likely culprit is the zero volt switch, rather than eg. the motor?

Any pointers as to possible failure modes? i am guessing that it will
be difficult to source an exact replacement.

Thanks, Jon N

[John Rumm]

On 15/05/2022 15:40, jkn wrote:
> Hi All
> I have a Sealey Pillar Drill - perhaps half a step up from the Aldi/Lidl/MachineMart basic pillar drills.
>
> It has always worked fine, but today it fails to start when I press the green
> button ;-(. Mains supply is known good. No noises of any sort.

Fuse would be a good first check. Then work back from there. Check mains
gets to the NVR switch, then out of it, then to the motor.

If it looks like the motor, then common failure mode is knackered start
capacitor. However you will usually hear a hum from it when powered in
this case. Next the contacts on the centrifugal switch. Check the rotor
and stator windings also have continuity.

> Any pointers as to possible failure modes? i am guessing that it will
> be difficult to source an exact replacement.

There are typically plenty of indiction motors that would do the job.
You might even be able to find a local motor rewind place that could fix
it.


--
Cheers,

John.

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[jkn]

On Sunday, May 15, 2022 at 5:10:34 PM UTC+1, John Rumm wrote:
> On 15/05/2022 15:40, jkn wrote:
> > Hi All
> > I have a Sealey Pillar Drill - perhaps half a step up from the Aldi/Lidl/MachineMart basic pillar drills.
> >
> > It has always worked fine, but today it fails to start when I press the green
> > button ;-(. Mains supply is known good. No noises of any sort.
> Fuse would be a good first check. Then work back from there. Check mains
> gets to the NVR switch, then out of it, then to the motor.
>
> If it looks like the motor, then common failure mode is knackered start
> capacitor. However you will usually hear a hum from it when powered in
> this case. Next the contacts on the centrifugal switch. Check the rotor
> and stator windings also have continuity.
> > Any pointers as to possible failure modes? i am guessing that it will
> > be difficult to source an exact replacement.
> There are typically plenty of indiction motors that would do the job.
> You might even be able to find a local motor rewind place that could fix
> it.

Thanks John
I have actually started taking a look now ... one slight surprise is that
there is a model number for the NVR switch, and that it seems possible
to get replacements. I am a cheapskate though...

The fuse is OK, so it's now a matter of checking the feed to the motor,
including the switch. I have found out the the drill originally cost
more than I thought (list price nearly £500).

Why do these things happen when "all I wanted to do was drill a
couple of holes..."?

Cheers, Jon N

[jkn]

Update - problem found and fixed

I have a small bench grinder nearby, and on closer examination
(having taken the NVR switch etc out) I discovered that on some
recent use I had rather carelessly allowed the cable to the drill
to ... ahem ... get partly ground away.

Cable now repaired, and safely clipped out of the way!

Embarrased-ly, Jon N

[John Rumm]

I have heard of problems caused by a missing "ground" before, I guess
this is kind of the inverse!

[Andrew]

On 15/05/2022 20:58, jkn wrote:

> Update - problem found and fixed
>
> I have a small bench grinder nearby, and on closer examination
> (having taken the NVR switch etc out) I discovered that on some
> recent use I had rather carelessly allowed the cable to the drill
> to ... ahem ... get partly ground away.
>
> Cable now repaired, and safely clipped out of the way!
>
> Embarrased-ly, Jon N
>

Cough. No RCD on that circuit ?

[Andy Burns]

Andrew wrote:

> jkn wrote:
>
>> I have a small bench grinder nearby, and on closer examination
>> (having taken the NVR switch etc out) I discovered that on some
>> recent use I had rather carelessly allowed the cable to the drill
>> to ... ahem ... get partly ground away.
>

> Cough. No RCD on that circuit ?

Are grindstones particularly conductive?

[ARW]

When I posted the photos of the molten hairdrier at a gym it was the
fire brigade that said it should have tripped the RCD.

Class II equipment is well known for having an earth:-)