3/21/12

kz400 3 phase recitifier on the cheap

When building the kz400 for last years scramble, I started piecing together a three phase rectifier, since the unit that came with the bike was rusted solid to the connectors. The original plan was to use three single phase bridged rectifiers with the idea borrowed from loudhvx on the kz400 forum.





By chance, I happened to find an off the shelf 3 phase rectifier that could be shipped to my door for less than $5 from China. Usually I would be a bit skeptical, but for such a small amount of cash I figured it couldn't hurt to try one out. In the end, the purchase was well worth it, and has been running flawlessly since being installed. To find the unit, search under the following criteria for a handful of suppliers Bridge Rectifier 3 Phase Diode 35A Amp 1000V SQL35A. I ordered mine through a company called Suntek Store. Here' s a pic of what it should look like.



While the original 3 bridge would have worked fine, it is obviously more wiring to do as well as surface area used.

Wiring the setup works as follows

~ Connect each of the three yellows, and order is not important.
+ Will go to your positive lead on your battery terminal.
- Will go to ground.

It's that simple.

One more note: The terminals on this unit are larger than an average spade connector. You can get larger spades to fit, so be prepared to pick up a few at your local parts store.

Edit: After a bit of review, I have noticed this unit may also work for a cb750. Anyone care to be a guinea pig?

2 comments:

d. said...

Thanks so much for posting this! I'm just finishing up an XS rebuild and trying to create a more reliable charging system on the budget. Any problems with yours so far? I just installed one of these yesterday but have yet to check the battery voltage. I've also seen a finned version of these which would be more efficient at cooling.

captain awesome said...

I have since sold the bike, but keep in contact with the current owner. He has been riding it off and on for a couple years now without any issues that I am aware of. It's been a while since I have touched an xs650, so I was unaware that they had a 3 phase charging system. If that's the case, then these would in fact be a good inexpensive update to the charging system.