Re: (ET) Prefer to back up faster.... E20

[RJ Kanary <rjkanary consolidated net>]

 That would accomplish what you wish.BUT, and there's 
ALWAYS a BUT................................the stabilizing 
series field will effectively weaken the main field, resulting in higher 
armature current. Keep your sniffer at the ready for the unmistakable 
scent of warm windings.<G>

                BTW when the card edge connector splits, you can 
suddenly find that feature available. At NO extra cost.An eye opener the 
FIRST time you make that discovery. :)

RJ

Max Hall wrote:
> Oh! Good Question! 26AE20AA
>
> -M
>
> On Wed, Feb 2, 2011 at 1:19 PM, RJ Kanary <rjkanary consolidated net 
> <mailto:rjkanary consolidated net>> wrote:
>
>     What model of E-20 ?
>
>     RJ
>
>     Max Hall wrote:
>
>         I'm a Boston-area guy, so I'm pushing a lot of snow. ("snOMG!"
>         "Snowmageddon!" etc.) And I really wish the higher speeds were
>         available on my E20 for reverse!
>
>         I'm looking at the schematics, and it seems as if all one
>         needs to do to have field-weakening for reverse as well as
>         forward is to remove a single conductor on the F&R switch
>         (more specifically, the portion of the F&R switch between P5-3
>         and P5-2 fed by wires 64 and 22-01) as it is a bypass for all
>         of the field-weakining resistors.  It seems as if the
>         high-current lock-out of field weakening would still work,
>         too,  (FW coil between card 4 pins 13 and 20 is controlled
>         partly by voltage across a shunt in series with the drive
>         motor) as its circuitry is separate from the F/R stuff.
>
>         So:
>         Anyone done this? If so, am I barking up the right tree?
>         Anyone know why I wouldn't want to do this? (Apart from
>         "backing up fast is scary"...)
>
>         Thanks, as ever, fellow ETers. Boy, am I working my E20 this
>         winter... love that machine!
>
>         -Max
>
>         -- 
>         www.maxmatic.com <http://www.maxmatic.com>
>         <http://www.maxmatic.com>
>         
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