This Is What A 500-Amp Voltage Drop Rectifier Looks Like

[MEXICOWANDERER]

This is a Schottky rectifier rated 500-amperes. 250 amperes per rectifier (The pyramid shaped things atop the bar)

At 100 amperes current (50 per pyramid) the voltage drop is .251. Example 15 volts in, 14.749 out.

The silver shiny plate with the pair of unthreaded 5/16" holes is not insulated. It is HOT and needs to be insulated. Use epoxy thermal compound to clamp to a heat sink like a gutted 70amp battery isolator. For perspective the two screws for the rectifiers are 1/4" diameter.

I am going to THREAD the 2 base plate holes, then screw-in a pair of cut-off 5/16" silicon-bronze bolt threads, then SOLDER the threads from beneath, the side that gets expoxied (epoxy INSULATES the big silver colored copper bar from the aluminum isolator case.

This drops the voltage a quarter volt on the WFCO "13.60 Volts Til I Die" power converter. 13.6 minus 2.51 voltage drop is 13.35 volts, for the Lifeline. The overkill amperage rating of the Schottky is to minimize voltage drop and make the rectifier bullet-proof. For $12.51, plus a free garbage-grade isolator finned housing. No the finned housing won't be "hot" it's isolated. For my purposes the WFCO 55 would do the same job as a Davy Crockett grade Master Woodsman Doombocker with magic wand costing >$200

[MEXICOWANDERER]

Wanna extra high Vf, use a Silicon Carbide Rectifier. Just heat sink it very very well.

[MEXICOWANDERER]

.275 but like any rectifier the higher its loaded the greater the Vf

Thats why I chose a 500 amp Schottky. It'll never go above .3

[wa8yxm]

Figured it was something like that Mex. very easy to do.. But what is the correct voltage drop across those thing, 0.275 or 2.75? Might need to know some day. i know high current Diodes sometimes have greater drop than low current ones.

[MEXICOWANDERER]

A keyboard the size of a postage stamp displaces decimals. Thank you. The Lifeline gets 13.35 volts
If it doesn't like it - tough. I'm charging a battery not designing a holrum for a fusion weapon. The average summer temp being the battery is inside with me in the A/C is around 84F. Weighed the battery again last week. About .5 gram total weight loss in almost 2-years withOUT float voltage correction.

[wa8yxm]

There appears to be an error in that .275 became, magically 2.75 in your post.

But otherwise, I've worked with hardware like that, Plan is good, but you may need more than one.

[MEXICOWANDERER]

Hee hee hee

Ancient chargers selenium rectifier plates, about 6" square with ceramic knob insulators.

Fire engine grade 50-amp generators the size of a 20 lb fire extinguisher that used 200 dollar voltage regulators (Back Then!) the size of a mahogany box of stogies.

200 watt color TV's that would properly cook a cheese sandwich inside, and needed a technician with mirror to "Do a convergence" every six months. Thirty feet tall masts with 16' long 40 element TV antennas, amplifiers, and rotators. "Ooooooo look the neighbor's antenna is turning, they must be getting ready to watch the "77 Sunset Strip" episode"

I have SINGLE 3,000 ampere rated 1,675 PIV rectifiers that have 2/0 braided leads with 1/2" holes. 200 lb center tap 16 volt center tapped transformers, that demand 50-amp 120 volt power. Their output is in excess of 350 amperes at 14.0 volts.

And a hydraulic pumped 3 phase circuit breaker rated at 3,200 volts 1,250 amperes. It's heavy and sloshes. Means it's full of mercury. TOYS TOYS TOYS

But the Schottky rectifier has a job to do. I am a Arctic Silver OEM and I hope my 16 oz of slo-cure epoxy gets here soon. The rectifier will be embedded in it on the gutted 70-amp isolator.

Sheesh, China can manufacture 500 aluminum extrusion plants and put a hundred thousand people to work and reduce the cost of heatsinks. Take a look on eBay sometime for the absurd cost of large heatsinks. Aluminum is cheap.

[westend]

Mex,
Why do they make such a thing? Understood your purpose but about the only other use I can fathom would be high current machine tools or some such.

FWIW, my old PD-808 deck-mount converter (circa 1970) has a rectification section that looks right out of Dr Frankenstein's lab. I guess it was built right at the onset of transistor based products.