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<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>> Thank you, Randall. Maybe that's the problem. I had
added a modern two</span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>> prong mini 10 amp fuse. Don't remember why, but I thought
the amp was in</span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>> the 3 to 5 range, but that must not be for pull in. I'll try
switching to</span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>> a slo-blo fuse at 8 amp too and see what happens.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>No point, IMO. From your
description, I do think you have a problem. Might be an internal short in
the "holding" coil (which should draw only about 1 amp), but my guess
is that the pull-in contacts are not opening for some reason, or are closing
back up again when things get hot.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>Just so we're on the same page, the A-type
solenoid has two windings internally. When the relay first closes,
current passes through both windings, producing a big strong jolt of magnetism
to move the solenoid plunger. Once the plunger has reached the end of
it's travel (against the inside of the housing), it is supposed to press on a
small button that pushes open the contacts under the housing outside, and cuts
the current through the high current "pull-in" coil. This
should happen very quickly, normally too fast to blow a 10 amp fuse. The
pull-in coil draws somewhere around 15-20 amps, while the holding coil is only
about 1 amp.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>Here's a photo where you can kind of see
the black button under the contact lever. <a href="https://goo.gl/W5Q23V">https://goo.gl/W5Q23V</a><o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>(Ignore the diode, it was a mistake.)<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>I only used the MDL-8 fuse because I had a
box of them on hand (scrounged from the trash when a previous employer shut
down a production line). Your 10 amp mini fuse should work just fine.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>Anything that blocks the solenoid plunger
from rising all the way can cause the fuse to blow. In my case, it
appeared to be a bit of gravel that found its way inside and jammed the
plunger. But misadjustment of the linkage can do it too, or even losing
the stop that controls how far the plunger can drop out of the solenoid. (On
some A-types, there is supposed to be a little rubber bumper mounted on the
stop arm. Mine was missing, so I replaced it with a bolt.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><a
href="http://s258.photobucket.com/user/TR3driver/media/A-type%20OD/DSCF0055.jpg.html">http://s258.photobucket.com/user/TR3driver/media/A-type%20OD/DSCF0055.jpg.html</a><o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;color:black'>Randall<o:p></o:p></span></font></p>
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