Jim Lynch wrote: > Ben Okopnik wrote: > >> This is the approach that I'll be taking (I like the way you think, Jim: >> it's brilliant, since it matches my own mental pretzel-bending... :) The >> only problem _there,_ as you can probably guess, is resistor wattage: >> the running current on this motor seems to be about 1.5A, I need to >> limit it to ~700mA (that being the specified running current of the old >> motor), so it seems like I need to experiment with 4-8 ohm resistors - >> which, according to Dr. Ohm, will require a _minimum_ wattage of 8-12W. >> Good engineering practice makes that 16-24W. >> >> In other words, *YIKES*. :) >> >> >> > Well, if you don't mind a series/parallel array I see on ebay > > LOT OF 25, 3 OHM 10 WATT 10W WIREWOUND RESISTOR, LOT#67 > <http://cgi.ebay.com/LOT-OF-25-3-OHM-10-WATT-10W-WIREWOUND-RESISTOR-LOT-67_W0QQitemZ370143952279QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item562e4c7d97&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1205%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50> > > For only $10. > > Jim. > So to get a 6 ohm resistor at 18 watts you'd take 4 of these in series in parallel with 4 more in series. That would give you 6 ohms at 20 watts. 3 x 4 = 12 in each leg and two of those in parallel would be 6 ohms. Resistors in parallel add power so you'd have 10 watts x 2, or 20 watts.
Seems cheap enough to me. Jim. _______________________________________________ Liveaboard mailing list Liveaboard@liveaboardnow.org To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to liveaboard-j...@liveaboardnow.org To unsubscribe send an email to liveaboard-le...@liveaboardnow.org The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/liveaboard@liveaboardnow.org The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
