cheap (I mean inexpensive) batteries

[bschwartz]

It's worth a shot at this point.  Now it is just figuring out how to best rectify the single phase 60v AC so as to not release the magic smoke from the Outback.........  I just liked the power supply because I could maintain the 120/240 from the ST head without any mods, and I could always switch off loads directly from it when needed (yes, I could put in switches, relays, breakers etc. to go back and forth....)

[Tom Reed]

In reading bob_g's suggestion on how to wire a single large rectifier it seemed quite complicated due to trying to polarize the coils. My thought, and I'm thinking of doing similar to feed a Outback MX60, is to use a separate smaller rectifiers for each of the 4 poles and buss the DC outputs together. Pretty easy to tell the polarity at that point. 

[bschwartz]

can the rectified dc be fed unfiltered into the mx60?

I have four evergreen 210W 12v panels (not up yet) but not a charge controller yet....... hmmm what should I get?

[mobile_bob]

Tom,
it would be far easier and probably less costly to do as you say, rectify each individually then connect them in parallel

easy because it is easy to check the polarity of a rectified coil and cheaper because low power rectifiers are cheaper
than high power ones.

and if you lose a rectifier you don't lose all capability as you would if you connected all the AC coils in parallel and rectified
the product.

bob g

[bschwartz]

would 4 of these do the job?

http://cgi.ebay.com/Motorola-MDA3502-35A-200V-bridge-rectifier-/400023927439?pt=LH_DefaultDomain_0&hash=item5d2348ba8f#ht_500wt_949

[Tom Reed]

Those rectifiers look like they would do the job. You will be seeing about 15a at 60v at best so those are well within spec.

As for feeding the mx60, I don't know if it would work. The closest I've seen is the output of an st5 through a transformer down to around 80v and rectified to a mx60. I believe the core of the transformer probably did provide some buffering though. Without a scope no real way to tell for sure.

It sure would be nice to have a 3 stage, temp compensated charge controller that would regulate via the field current on a modified st5 for charging 48 volt battery banks. Probably could even sell a few of them to off-gridders like my self.

[LowGear]

OK!

I finally got to Costco.  Their deep cycle marine batteries are a bout 70 and come with a standard 12 month replacement or 36 month prorated refund warranty.  Costco labeled them "group 14" but they looked very "group 24" to me.  They will probably be my break-in and test batteries on the converted Polaris ATV.  The equivalent Trojan "pretty damn good" units are about $200.

Casey

[LowGear]

I bought a new battery and returned dead one to Costco today.  The Costco battery failed after six years of service!  Can you believe it, only six years!    They gave me a $9.56 core rebate for it.  What a great deal.

Casey

[mbryner]

Unfortunately, the power supply, and the draw from the Outback are greater than what the 6/1 can provide.  If there is no way to limit the current (total wattage) draw from the Outback, then this whole thing may be a HUGE BUST!!!

Hey Brett,  I'm a little late here: how did you figure it out?   From experience w/ my VFX3648 in the past few weeks, there is an option where you can limit the amperage when it is in charging mode back to the batteries.   I know you're using a 48 V power supply to charge the batteries with, and there's probably no way to limit that amperage, but there may be an option to limit how much current the VFX sends into the grid.   I've thought of using power supplies for charging, but if there's no way of limiting the current all you'll get is a stalled 'roid.  At one time we discussed using a Xantrex C40 charge controller.   It's a PVM unit that does max 40 A @ 48 V DC -- about 2000 watts.   That would be a satisfactory load for a 6/1.   They aren't that expensive.   $140 new at altestore.com, cheaper used.   In my case, if changing the field current on the ST head doesn't work, then I may try the C40.

can the rectified dc be fed unfiltered into the mx60?

This was discussed on another thread since, but I might as well answer it here too.   It won't work.   About a year ago, Geno tried it with some success.   It charged but after a while the screen on his MX60 got garbled.   It fixed after he rebooted it.   About a month or two ago I tried it unfiltered into a MX80 instead of MX60.  (They're pretty much the same.)   The MX80 locked onto the rectified DC, then dropped, and cycled quickly like this over and over.   For anyone trying this, at least use a filter like a coil choke, or large capacitor, or both in an LC circuit to smooth the ripple.

Didn't mean to divert the thread but I saw some unanswered questions...   So, Casey, what are you using the battery for?

[BioHazard]

I bought a new battery and returned dead one to Costco today.  The Costco battery failed after six years of service!  Can you believe it, only six years!    They gave me a $9.56 core rebate for it.  What a great deal.

Casey

Not bad, what kind of service was the battery used in?

[LowGear]

The battery was used in a Tacoma 4 cylinder.  I'm currently going for every light to be "ON" on the dash.  I've got brakes, engine and airbags covered so far.  Oh, and emergency brake most of the time.

Casey