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True,
but it's just an itsy bitsy little connection! I.e., the bulbs can't
conduct enough juice to allow anything to be hurt. >>> "T Humphrey" <thumphrey mynra com> 1/26/2004 12:48:50 PM >>> But if you do this, then you connect the pack to the frame, through the lights. Exactly what you don't want. Stay Charged! Hump > > >-----Original Message----- >From: Bob Murcek [mailto:rmurcek geisinger edu] >Sent: Monday, January 26, 2004 12:45 PM >To: elec-trak cosmos phy tufts edu >Subject: (ET) Re: pack not isolated from frame?? > > >Just had a thought about catching frame grounds early. > >I've noticed that in industrial situations where 3-phase delta- connected >power (three hot wires totally unrelated to ground, no neutral) is used, >electricians sometimes connect a light bulb from each of the hot wires to >ground. Since the three hot wires don't have a relationship to ground, the >bulbs all glow equally running in sorta-series. If there's a ground fault, >i.e., if one of the hot wires gets connected to ground by accident, the bulb >for that wire goes out. > >We could do the same thing, I think. Just connect two small (something that >would take a least a quarter of an amp) 36-48 volt bulbs, one from the plus >end of the pack to the frame, and one from the negative end of the pack to >the frame. Properly fused of course. Maybe with one fed from the load side >of the key switch so that they were only on when the tractor was. > > >>>> Dave & Debbie Barden <daveb seanet com> 1/26/2004 8:38:50 AM >>> >because of some red-orange paint I thought for a while it might be a >wheelhorse >but the the GE symbol is there on the front grill. there's no hole up front > >where the PTO plug may've been. The tractor has been painted JD green >including >the name plate on top of the dash unfortunately and the data plate under the > >hood isn't there. Unless I can get some info off the painted plate atop the > >dash I'm afraid all I'll have to go on is physical description. the >tractor's >on the island and it'll be friday before I can get there again. > >thanks for the warning/confirmation that I've a dangerous situation that >must >be fixed immediately. I'm taking that to heart... > >dave >seattle > >> As my Dad, the electrician who had 30 years of experience with DC >> operated overhead cranes would say, "Son, you've got something that's >'gone >> to ground'." >> {Actually, in most cases two items have to fail to make obvious >> symptoms.} >> >> The most common culprits in the Elec-Trak(r) are....... >> 1.) Armature resistor contactor bushings. >> 2.) Armature terminal bushings on the traction motor, or brush rigging. >> 3.) Lift motor. >> This situation is VERY dangerous, and must be investigated and >repaired >> immediately. >> I have never seen a tractor with the PTO outlet where you have >described >> it. Give us the numbers from the data plate, under the hood, and I think >we >> can puzzle it out. >> >> ----- Original Message ----- >> From: "Dave & Debbie Barden" <daveb seanet com> >> To: <rjkanary nauticom net>; <tcoate coate org>; >> <elec-trak cosmos phy tufts edu> >> Sent: Sunday, January 25, 2004 2:54 PM >> Subject: pack not isolated from frame?? >> >> >> > >> > I was working on my modified E15 (?) today, and while loosening a >> connection on >> > one the cable connections I grounded to the body with the wrench and got >> an >> > ugly juicy spark. That doubly surprised me because I am always careful >> around >> > battery terminals and potential grounds but also because I thought that >if >> the >> > pack was not grounded to the frame you wouldn't/shouldn't get current >> flow?? >> > >> > So what gives here am I under a mis-impression and showing my ignorance >or >> do I >> > have a ground somewhere that I shouldn't have?? >> > >> > Also since this tractor has been modified by the previous owner I don't >> really >> > know what model it is. My E12S has the PTO plug up front on the left. >> This >> > one has the PTO plug down by my right foot. Would this be an E15 or E20 >> or??? >> > >> > thanks much, >> > dave >> > Seattle >> > E12S >> > E?? modified >> > >> > >> > >> > >> > >> > >> >> > > > > > >_______________________________________________ >Elec-trak mailing list >Elec-trak cosmos phy tufts edu >https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak ><https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak> > > > > _______________________________________________ Elec-trak mailing list Elec-trak cosmos phy tufts edu https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak |