[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: Re: (ET) PV powered ET more questions



thanks all.  yes this all helps.  it's better than school!

to clear up the confusion about the 1v per battery...

I have the four batteries in the back wired together in series total 
voltage 
right about 30.something...  I have only the cable coming off the last 
battery going to the shunt connected.   I then check voltage between 
battery 
one and the frame and get a voltage reading 1.2something volts,  go to 
battery two and get a reading of 2.4 etc until I get to the last battery 
and 
get a reading of 4.8v I think it was.

that's when I unhooked the cable from the pack that goes to the shunt and 
checked it with the ohmeter expecting to get a reading and didn't.

from one of the previous posts I think I should try this with an analog 
meter 
next time I'm on the farm.

thanks all, I'm going to print off all responses and take with me this 
wkend.

dave 
seattle


--
Open WebMail Project (http://openwebmail.org)


---------- Original Message -----------
From: JAKrug EBAerospaceAndDefense com
To: daveb seanet com, rmurcek geisinger edu
Cc: Elec-trak cosmos phy tufts edu
Sent: Wed, 5 May 2004 09:25:28 -0400
Subject: RE: Re: (ET) PV powered ET more questions

> Really really.
> It got me once.
>  
> I am a little confused about the 1 volt per batt statement.
> If you check different points in the battery pack to ground you will 
> see were the short is in relation the the pack. Another way to check 
> if it is a real short or just dirt is check the current that flows 
> from the pack to the frame. Use a limiting resistor in series with 
> the meter so that you don't blow the fuse in your meter. You won't 
> get much current flow though dirt. If you have the batteries 
> disconnected you can use an ohm meter between the battery cable and 
> the frame. Readings in the megohm range and higher are usually dirt 
> or contamination.     hope this helps. Jeff    
> 
> Sincerely, 
> Jeffrey A. Krug 
> Test Engineer I 
> The Ensign-Bickford Aerospace & Defense Co. 
> 640 Hopmeadow Street                
> P.O. Box 429 
> Simsbury, CT 06070 
> Phone: 860-843-2072 
> Fax: 860-843-2069 
> E-Mail: jakrug EBA-D com 
> Pager 860-802-4153 numeric
> 
>  
> 
>    -----Original Message-----
>    From: daveb [mailto:daveb seanet com]
>    Sent: Tuesday, May 04, 2004 7:26 PM
>    To: rmurcek
>    Cc: daveb; Elec-trak
>    Subject: Re: (ET) PV powered ET more questions
> 
>    really?  maybe that explains why the my digital meter seems
>    schizophrenic at times.   It wasn't damp at all when I was doing the
>    metering though, and I got a zero reading before hooking the pack 
> up   to the harness.  after hooking up to the harness I'd get just a 
>   little over 1v per batt and a total of about 4.8v from all four.  
> I   don't think that could be dust.  could it?
> 
>    thanks,
> 
>    dave
> 
>    -- 
>    Open WebMail Project ( http://openwebmail.org)
> 
>    ---------- Original Message ----------- 
>    From: "Bob Murcek" <rmurcek geisinger edu> 
>    To: <daveb seanet com> 
>    Cc: <Elec-trak cosmos phy tufts edu> 
>    Sent: Mon, 03 May 2004 23:49:29 -0400 
>    Subject: Re: (ET) PV powered ET more questions
> 
>    > If you're using a meter with really high input resistance, like 
> a   digital meter, it would take nothing more than damp dust in the right
>    place to get a voltage reading to the frame.... 
>    > 
>    > >>> "RJ Kanary" <rjkanary nauticom net> 5/3/2004 9:32:54 PM >>> 
>    >       Both the meters can go to ground, especially if they have
>    ever gotten 
>    > wet. It would not pass much current, until another item goes to
>    ground, with 
>    > the resultant arcing. 
>    >   Other prime suspects are the armature contactors,  The 
> bushings   around    > the large terminals. , the traction motor 
> armature terminals, and   that    > perennial favorite, the Delco® 
> lift motor.    >    > ----- Original Message -----    > From: 
> "daveb" <daveb seanet com>    > To: "Chris Zach" 
> <czach computer org>; "Markus Lorch"   <mlorch vt edu>    > Cc: 
> <Elec-trak cosmos phy tufts edu>    > Sent: Monday, May 03, 2004 
> 9:33 PM    > Subject: Re: (ET) PV powered ET more questions    >   
>  > > over the wkend I finally got the chance to start the conversion 
>   of my E12S    > to    > > the alltrax controller.  I'm not nearly 
> finished yet as I am   taking this    > > opportunity to thoroughly 
> check out the wiring for shorts, clean   things up    > > etc.    > 
> >    > > so far I've removed and re-installed the rear batteries 
> after   painting the    > > box and installing the plastic battery 
> bags from Bill G.  Before   I started    > I    > > was getting 5v 
> between the pack and the frame.  with the   batteries cleaned    > 
> up    > > in the new bags and connected together but not to the 
> wiring   harness I    > read    > > 0volts.  when connecting the 
> cable that runs to the shunt I read
>    4.8v    > again.    > > Ok I reason even though I inspected the 
> wires in and out of the   box    > something    > > is grounded but 
> where.  So I get the bright of idea of using the   ohm meter    > > 
> but find nothing!  No continuity anywhere between the cable and  
>  the frame    > and    > > yet I read 4.8v.  How can that be?  is it 
> because my ohm meter's   battery    > is    > > only 9v, old and 
> probably needs replacing?    > >    > > The next time I'm at the 
> farm I'll disconnect the cable from the   shunt and    > > measure 
> voltage to the frame and proceed downstream    > > 
> disconnecting/checking/reconnecting as I go.    > >    > > oh and I 
> measure 15.8ohms across the motor's field.  is that   within range?  
>   > I    > > seem to remember someone not long ago mentioned field 
resistance
>    but I 
>    > don't 
>    > > remember what the correct amt was. 
>    > > 
>    > > any other ideas or comments would be greatly appreciated. 
>    > > thanks, 
>    > > dave 
>    > > seattle 
>    > > 
>    > > -- 
>    > > Open WebMail Project ( http://openwebmail.org) 
>    > > 
>    > > 
>    > > ---------- Original Message ----------- 
>    > > From: Chris Zach <czach computer org> 
>    > > To: Markus Lorch <mlorch vt edu> 
>    > > Cc: Elec-trak cosmos phy tufts edu 
>    > > Sent: Thu, 29 Apr 2004 22:25:25 -0400 
>    > > Subject: Re: (ET) PV powered ET more questions 
>    > > 
>    > > > Um no. 
>    > > > 
>    > > > If the higher capacity batteries are in series with the low
>    capacity 
>    > > > ones and you run the charger, what will happen? Either you will
>    boil 
>    > > > and overcharge the lower ones to charge up the higher ones, 
> or   you will    > > > never fully charge the higher capacity 
> batteries.    > > >    > > > The "right" solution is a 36 volt 
> inverter. If you're only   going to use    > > > a little bit of 
> power, then a 24 volt (better) or a 12 volt   could *do*.    > > > 
> However two of your batteries will be out of sync on charging,   and 
>    > > > you'll still wind up overcharging some batteries on the 
> pack to   get    > > > everything back in sync.    > > >    > > > 
> Get a Trace DR3624. You'll have 3,600 watts of power, and it   will  
>   > > > pull the pack down evenly. With that you should be able to 
> run   anything.    > > > Chainsaw, etc.    > > >    > > > Chris    > 
> > >    > > > Markus Lorch wrote:    > > >    > > > >>This is so I 
> can use Solar PV to charge my batteries,    > > > >>carry a small 
> inverter on the ET to run a small    > > > >>commercial inverter for 
> string trimmers and electric    > > > >>chain saws (Price 
> Club/CostoCo had a nice deal on    > > > >>1.75kw Xantrex inverters) 
>    > > > >>(and run the fridge, a radio and a couple of lights in    
> > > > >>a pinch.) (There are a LOT of trees hanging over a LOT    > 
> > > >>of electric lines anywhere I drive, many more than    > > > 
> >>10-15 degrees past vertical)    > > > >    > > > >    > > > > The 
> previous owner of my E20 has put two larger (higher   capacity)    > 
> > > > batteries in my elec-trak. These drive the 12V components. I   
> also    > > > > have a 300W inverter hooked up (cheap $20) to which 
> I connect   my    > > > > small electric trimmer. It worked fine all 
> afternoon   yesterday.    > > > >    > > > > Maybe you can also have 
> two batteries be larger?    > > > >    > > > > see my other post on 
> chargers.    > > > >    > > > > Markus    > > > >    > > > >    > > 
> > > _______________________________________________    > > > > Elec-
> trak mailing list    > > > > Elec-trak cosmos phy tufts edu    > > > 
> > 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    > > ------
> - End of Original Message -------    > >    > >    > > 
> _______________________________________________    > > Elec-trak 
> mailing list    > > Elec-trak cosmos phy tufts edu    > > 
> 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    >    >
> 
>   _____
> 
>    > IMPORTANT WARNING: The information in this message (and the
>    documents attached to it, if any) is confidential and may be legally
>    privileged. It is intended solely for the addressee. Access to 
> this   message by anyone else is unauthorized. If you are not the 
> intended
>    recipient, any disclosure, copying, distribution or any action 
> taken,   or omitted to be taken, in reliance on it is prohibited and 
> may be   unlawful. If you have received this message in error, 
> please delete   all electronic copies of this message (and the 
> documents attached to   it, if any), destroy any hard copies you may 
> have created and notify   me immediately by replying to this email. 
> Thank you. 
>    ------- End of Original Message -------
------- End of Original Message -------