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Insulating Washer Material Question

R

Rileyesi

Jan 1, 1970
0
First, thanks to all who replied to my request for sources for insulating
washers.

One vendor quoted me PVC washers as opposed to the linen based phenolic washers
that we have used in the past, but they could not tell me the difference it
would make in the insulating properties. I hope someone can shed some light on
this for me.

The application is in an office environment, so no temperature or humidity
extremes. The signal that will be insulated is a variable 0-15 VDC at 100 mA
max. This will be used on the back of an analog panel meter and the function
of the washers is to isolate the signal from the metal meter case.

I think the PVC will do just fine, but would like any thoughts the group may
have.

Thanks.
 
J

John Popelish

Jan 1, 1970
0
Rileyesi said:
First, thanks to all who replied to my request for sources for insulating
washers.

One vendor quoted me PVC washers as opposed to the linen based phenolic washers
that we have used in the past, but they could not tell me the difference it
would make in the insulating properties. I hope someone can shed some light on
this for me.

The application is in an office environment, so no temperature or humidity
extremes. The signal that will be insulated is a variable 0-15 VDC at 100 mA
max. This will be used on the back of an analog panel meter and the function
of the washers is to isolate the signal from the metal meter case.

I think the PVC will do just fine, but would like any thoughts the group may
have.

Thanks.

I have little doubt that the electrical properties of almost any
plastic are sufficient. The mechanical properties are what you need
to worry about (creep, crazing, cracking under stress, etc.)
Reinforced phenolic is very stable under mechanical compression.
 
C

CFoley1064

Jan 1, 1970
0
Subject: Insulating Washer Material Question
From: [email protected] (Rileyesi)
Date: 4/27/2004 10:15 AM Central Standard Time
Message-id: <[email protected]>

First, thanks to all who replied to my request for sources for insulating
washers.

One vendor quoted me PVC washers as opposed to the linen based phenolic
washers
that we have used in the past, but they could not tell me the difference it
would make in the insulating properties. I hope someone can shed some light
on
this for me.

The application is in an office environment, so no temperature or humidity
extremes. The signal that will be insulated is a variable 0-15 VDC at 100 mA
max. This will be used on the back of an analog panel meter and the function
of the washers is to isolate the signal from the metal meter case.

I think the PVC will do just fine, but would like any thoughts the group may
have.

Thanks.

Since you're not talking about high voltage or high frequency, the primary
difference between the two washers will be mechanical. PVC washers will be
relatively soft, and will deform and will tend to tear or pierce through.
However, they're much easier to punch/stamp, and should cost less. They should
be O.K. as long as you watch the torque.

Why not just use insulated 5-way binding posts? They're relatively inexpensive
and commonly available.

Good luck
Chris
 
S

Søren

Jan 1, 1970
0
[email protected] (Rileyesi) wrote in

One vendor quoted me PVC washers as opposed to the linen based
phenolic washers that we have used in the past, but they could not
tell me the difference it would make in the insulating properties. I
hope someone can shed some light on this for me.

The application is in an office environment, so no temperature or
humidity extremes. The signal that will be insulated is a variable
0-15 VDC at 100 mA max. This will be used on the back of an analog
panel meter and the function of the washers is to isolate the signal
from the metal meter case.

I think the PVC will do just fine, but would like any thoughts the
group may have.

If the signal is fairly low frequency and the washers are not compressed
to the point og tearing, you are in the green.


--
Venlig hilsen,
Søren
* If it puzzles you dear... Reverse engineer *
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