[R-390] Advice - Proper Use of Meggers

[rbethman]

Mike,

    These are used normally to test high voltage cables, transformers,, 
and generator windings.

    I don't believe that testing capacitors is recommended.

Bob - N0DGN

Leigh Sedgwick wrote:

>I recently picked up a megger but, honestly, I don't know
>much about them.  They are apparently great for checking
>leakage through caps which is the main reason I bought it.
>
>For the record, it is a old Navy unit made by Winslow
>Teletronics, Inc., Model ZM-63/PSM-35 with a Navy
>designation of AN/PSM-35.  It measures Megohms resistance at
>500V.
>
>I notice that I can vary the output voltage by rotating the
>crank at a slower speed but the readings fluctuate.  So I
>take it, that the proper use requires rotating the crank at
>normal speed and full-voltage output?  While 500V is fine
>for some caps, it typically exceeds some of the smaller caps
>found in receiver boat anchor receivers.  So, does one need
>a smaller unit for lower voltage caps to get reliable
>readings.  
>
>Sorry for my ignorance on the subject, I've just never used
>one of these.  Can someone shed some light on this subject
>for me or point me at a reference for their proper use.  Any
>manuals available for this animal?
>
>BTW, just finished tearing apart my RF deck and cleaning all
>the gears.  I found that even a clean looking unit like mine
>was before I started, should be rebuilt...many gears were
>stuck together from hardening of the lubrication oil even
>though they looked quite good to the naked "eye".  I'm
>looking forward to experiencing the "smooth" action of an
>R-390A.
>
>Hey thanks all...
>
>73 de Mike
>K7PI
>Mercer Island, WA
>_______________________________________________
>R-390 mailing list
>R-390@mailman.qth.net
>http://mailman.qth.net/mailman/listinfo/r-390
>
>  
>

-- 
<                      Bob Bethman - N0DGN
+-------------------------------+----------------------------------+
| N0DGN AMRadio Manassas, VA    |          Home Builder            |
+-------------------------------+----------------------------------+
| Bob Bethman                \\\|///     " The absence of a danger |
| <rbethman@comcast.net>    \\ ~ ~ //      signal does *NOT* mean  |
| Bethman Fine Homes        (/ @ @ /)      that everything is OK " |
+-------------------------oOOo-(_)-oOOo----------------------------+
|               <http://home.comcast.net/~rbethman>                |
| 1 BC-610I w/BC-614I,1 T-213/GRC-26 w/BC614I 1 '51 Collins R-390A |
| 1 '67 EAC R-390A, Heathkit DX-60, Apache, Mohawk, SX-101, HT-32A |
+------------------------------------------------------------------+
|           Amateur Astronomer - Celestron Nexstar 8               |
|             12" f5 Dob coming soon!  Being built                 |
|                  Meade ETX-60 (Got it back!)                     |
|               38 Deg 46.8' N - 77 Deg 28.5' W                    |
+------------------------------------------------------------------+
|   Opinions expressed are that of my own and do not necessarily   |
|         coincide with or represent those of ANYONE else          |
+------------------------------------------------------------------+
  ALL E-mail received and sent scanned by AVG & Norton Anti-Virus>