Lee, I created the pdf's to be compatible with Acrobat 4.0 and higher, so I'm not sure how reliable they can be read with 3.0. I have another diagram that shows how the rest of the charger (magnetics and power semiconductors) interface to the control card. I should have posted that at the same time, it will be much more informative. Some of the more interesting portions of the circuit; upper left - very old, but very reliable power supply with wide input range. There are much better (efficiency etc.)supplies available today, but this design is probably 20 years old and is probably on almost every GE based forklift. bottom left - Green wire integrity test. This is a low current detection circuit that checks to see if there is leakage to ground before closing the main AC contactor. Top/Top left - Hysteretic control. IGBT gate drive and current limit circuit. This is very reliable and will protect the IGBT's with a direct short on the charger output terminals. Middle right - ground fault circuit interrupt - This was on the original TEVan chargers but was removed because it occasionally had false trips. This circuit was active while the van was charging. It was replaced with a commercial GFCI interrupt circuit breaker mounted on the battery charger enclosure. I'll post the functional diagram later today. If you have any questions let me know. Rod -----Original Message----- From: Lee Hart [mailto:leeahart@earthlink.net] Sent: Saturday, March 22, 2003 2:11 AM To: rodhower@Ameritech.Net Subject: Re: TEVan charger schematic Rod Hower wrote: > > I posted some scanned schematics of the TEVan > battery charger control card. > http://www.qsl.net/w8rnh/battchgr.pdf > This is 1 Mb and may be somewhat difficult to see all > component values. > http://www.qsl.net/w8rnh/batchgr.pdf > This schematic is more detailed with all components > easy to see. Thanks, Rod. I downloaded the 2nd one (all 3.3 megs worth on my dial-up -- it took 15 minutes). But then Acrobat 3 just gave me a "colorspace error" and displays nothing but blank pages. So I downloaded the smaller 1 meg file. It displays fine, but you're right; it is too fuzzy to read most of the printed text. Also, this style of schematic has lots of little disconnected subcircuits. Without a block diagram it's hard to tell how they all tie together. (It would probably help if I could read the text :-) So, could you provide an overview of what it does? For example, I don't see any AC input, rectifiers, or output voltage and current control devices, or any place for the batteries to connect. -- Lee A. Hart Ring the bells that still can ring 814 8th Ave. N. Forget your perfect offering Sartell, MN 56377 USA There is a crack in everything leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen