wrote:
On Wednesday, 22 July 2020 21:14:05 UTC+1, Wingnuts wrote:
replying to The Medway Handyman, Wingnuts wrote:
Hi, I have a Henry NVR200 which is over heating.

I've stripped it down and cleaned it as best I can.. The brushed have about
15mm left on them and the fans underneath the motor were pretty clean but I
soaked them in warm soapy water nonetheless and then used a bottle brush to
get in-between them. I then attached a drill to the nut and ensuring the
correct direction I spun it up to dry out any moisture that remained, if any.

The lack of obvious fluff and dirt and that it was pretty clean in the first
place bothered me; I was expecting something more significant to explain the
tripping of the thermal cut-out. I cleaned everything and re-assembled Henry.

There was a noticeable improvement in the suction and the motor didn't trip
out...... until just now.

So, before I strip it down again, could the thermal cut-out be faulty? I'm
guessing it's unlikely as Henry runs for a short time before it cuts out, then
it starts up again. I'm guessing this is due to the thermal cut-out cooling
slightly etc etc.

Does anyone have any advise on troubleshooting the actual cause or a process
of elimination I should follow?

I know this post is over 10 years old, but I have faith in you lot

Thanks in advance,

I'd check its idle current and/or lube the bearings.
Used vacs also benefit from clearing the airpath out & cleaning/replacing filters.


NT

http://www.wobblycogs.co.uk/electron...c-henry-motor/

"Start by simply giving the motor a good visual inspection. If the insulation
in the windings has failed youll likely see sooty burn marks somewhere on
either the stator or the rotor. The most common location for a failure is
just under the commutator (the divided copper area the brushes run on)."

Using your Kill-O-Watt meter, the vacuum power consumption is
likely way out of line with reality.

Without any special prep, I just checked my vacuum cleaner.

Nameplate rating: 7.4 amps
Test (tube open): 6.2 amps (bag is full though)
Test (tube closed): 6.8 amps

I was expecting a lower reading, but I guess the full
bag is doing that to the power.

And the meter has trouble measuring the power,
because motors like that one run dirty. There would
be a lot of sparks coming off that commutator
and brush assembly.

But at least the power footprint, is less than the nameplate.

Paul