Re: (ET) DC-DC Converters - Lot of 6

["David Roden (Akron OH USA)" <roden ald net>]

On 26 Mar 2002 at 12:57, Chapin, Tim wrote:

> 6 dc-dc converters on ebay..

Careful!  These are for 24 and 48 volt nominal input, so unless you've 
upgraded your ET to 48 volts, they wouldn't help much (you'd still have to 
tap the pack).  The specs say "18 to 36 volts" for the 24 volt units, but 
that's intended to leave "headroom" for higher voltage during charging, 
not 
for routine operation.  

If you tried to use the 48 volt units instead, you'd have problems. They 
probably won't put out full current, and are more likely to overheat, when 
run below nominal voltage.  Also, when you loaded the tractor and the pack 
voltage sagged, they'd probably drop out. 

Finally, each is capable of delivering only 20 watts.  That's about 2 amps 
at 12 volts -- barely enough to run the headlights, if even that.  You 
might 
be able to parallel all six and get 8-10 amps (DC:DC converters don't 
share 
loads perfectly, so you probably wouldn't get 12 amps), but you'd still 
have 
the input voltage problem.

These DC:DCs probably have some uses, but I wouldn't buy them for an ET's 
lights and/or lift.


David Roden - Akron, Ohio, USA
1991 Solectria Force 144vac
1991 Ford Escort Green/EV 128vdc
1970 GE Elec-trak E15 36vdc
1974 Avco New Idea 36vdc
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Thou shalt not send me any thing which says unto thee, "send this to all 
thou knowest."  Neither shalt thou send me any spam, lest I smite thee.
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Est. yearly US cost to safeguard Persian Gulf oil supply: $50 billion
Est. 2001 value of US crude oil imports from Persian Gulf: $19 billion
                                                          -- Harper's 
Index, 
April 2002
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =