The Mark Hanson Collection
DIY EV Hardware

The circuits below were designed by Mark Hanson. He's used most of them with his EVs. A few are related projects for renewable energy systems which may be used to charge EVs. A couple are unrelated to EVs, but are included here just for fun.

Mark is releasing these designs into the public domain for the good of the EV cause. Please note however that these aren't cookbook instructions. Using them calls for some electronics expertise on your part. You'll have to adapt the design for your particular situation, lay out and fabricate a circuit board, figure out how to mount components, design a housing, etc.

For circuit board design, Mark recommends Express PCB free schematic drawing and layout software. All the projects that use controllers were done with the Mon08 programmer and development system from P&E Micro. If you don't want to write your own code, Mark will supply programmed MC68HC908QY4 microcontrollers for $20 each. Write to Mark E. Hanson, 184 Vista Lane, Fincastle, VA 24090 or email him at

More information on these designs is available at Mark's website, Selectrol Electronics.

EV Projects
Mark's most recent DC motor controller, as used in his E-Porsche (firmware source here) pdf
Small PWM controller for variable fan speed and accessories in EV pdf
Charger using microwave oven transformer (version for 84v battery) pdf
Charger for solar electric boat Jerry Dycus and Mark are building (similar to above, for 48v battery) pdf
Lee Hart's battery regulator - schematic by Mark pdf
Lithium Ion battery charge equalizer (summer 2009)
pdf
Battery scanner individually and simultaneously monitors up to 24 batteries in an EV's pack pdf
Water level detector for basement or bilge flashes LED faster as level rises - also can sense electrolyte level in batteries with carbon or stainless probes pdf
DC Watt-hour counter tracks EV battery level, or RE system energy production pdf
Inverter converts 24-72vdc to about 1400 watts of 120v or 240v 60Hz AC, for EV air-con and other accessories pdf
Adapter converts existing ICE tachometer to work with EV, using Hall pickup and magnets pdf
Flipflop connects in line with NEV's Hall speed sensor to raise governed speed to 45mph.
(Caution: make sure brakes and steering suit the higher speed!)
pdf
EV Power Control (as used in Mark's Ghia) - precharge, emergency disconnect, heater control, high pedal startup lockout, full pedal controller bypass pdf
Addenda to above (as used in Mark's Porsche), with ground fault detector pdf
Renewable Energy Projects
Booster-regulator charges a 24v battery from the variable 8v-30v output of a wind machine pdf
Small PWM controller for a woodstove fan pdf
Solar differential thermostat pdf
Two-axis solar tracker pdf
Switch on outside light to partly discharge PV battery to 90% SOC, for next day's solar collection pdf
Log Annunciator - monitors woodstove temperature and controls fan. When the fire burns down to one log, it plays Shel Silverstein's tune Put Another Log On The Fire pdf
General Projects
General purpose buck converter - input 25-30v, output 18v 3a / 12v 250ma / 5v 250ma pdf
Four oscillator designs based on crystal, capacitor, and ceramic resonator references pdf
Pink noise generator to mask noise for a good night's sleep pdf
Stabilizer for DVDs infected with sync scrambling copy protection (not intended for illegal use) pdf