Re: Window Screen Tamper

[Jim <alarminex@xxxxxxx>]

On May 24, 11:30=EF=BF=BDam, "ABLE1" <royboynos...@xxxxxxxxxxxxx> wrote:
> "Jim" <alarmi...@xxxxxxx> wrote in message
>
> news:67e77a2b-22a8-4d30-b270-2e046235a672@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> On May 23, 10:12?pm, "ABLE1" <royboynos...@xxxxxxxxxxxxx> wrote:
>
>
>
>
>
>
>
> > By a 'Hipot Tester' ?you mean a Megger(brand name). ?I have used a Megg=
er
> > to
> > test insulation on motor windings to ensure the resistance is within
> > correct
> > values after a motor re-wind and it did not have any possible shorts to
> > the
> > motor case. ?It may work in this case but I would think it is
> > questionable.
> > I say this because it would seem to me that the insulation at the point=
 of
> > failure would have to be in close proximity to the frame if not touchin=
g
> > it.
> > That being said, how can this be assured inside of the frame?? ?Then ag=
ain
> > maybe a tolerance value can be developed if you do enough QC and a bell
> > curve can be produced. ?The voltage on the contacts would not be an iss=
ue
> > unless it is directly shorted to the frame.
> > I'm not so sure about that. If there is any resistance ( which there
> > will be) across the contacts of the reed, the Hypot could cause an arc
> > and either burn or weld the contacts together.
>
> Actually no.
>
> When you connect the Megger leads you would connect to the metal frame an=
d
> the end of one wire lead. =EF=BF=BDThere is no current flow..............=
... unless
> there is bad wire insulation and a short is produced to the frame at the
> high voltage potential. =EF=BF=BDIt all happens when you turn the crank. =
=EF=BF=BDIf all is
> in good condition the needle never moves since no current flows.
>
> If current does flow and the reed is destroyed.............. well it was =
a
> bad set up to start with so it makes little difference.

That's right.

The switch is destroyed even if a repairable problem is found.


>
> Of course the test needs to be performed with the tamper magnet in place =
to
> keep the switch closed, otherwise you are only testing one side of the lo=
op.-

Yep