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AltFuel · 07-03-2011, 10:03 AM

The quick rundown on the 1998 GMC Sonoma

Batteries - 14, 6 Volt DEKA GC25
Motor - Advance DC FB-4001A
Controller - Open Revolt Cougar, 500 Amp

Using a spare Hass 300-s a current/voltage meter is measuring the voltage and current at battery pack every 0.1 seconds. Multiplying these values gives the power being drawn from the batteries and then integrating the power values gives the energy usage. From this info as well as coast down tests I found my coefficient of drag to be 0.52 with frontal area of 24 sq ft. I have a horrible CdA of 12.4 . I have not easily measured the rolling resistance but I am sure it is on the poor side. These numbers agree pretty well with the EV calculator.

The next step is to directly measure speed and temp so I can reliably get numbers on Wh/mile before I start improving the CdA and rolling resistance.

07-03-2011, 10:03 AM	#2 (permalink)
AltFuel EcoModding Lurker Join Date: Jun 2011 Location: United States Posts: 8 Thanks: 0 Thanked 0 Times in 0 Posts	The quick rundown on the 1998 GMC Sonoma Batteries - 14, 6 Volt DEKA GC25 Motor - Advance DC FB-4001A Controller - Open Revolt Cougar, 500 Amp Using a spare Hass 300-s a current/voltage meter is measuring the voltage and current at battery pack every 0.1 seconds. Multiplying these values gives the power being drawn from the batteries and then integrating the power values gives the energy usage. From this info as well as coast down tests I found my coefficient of drag to be 0.52 with frontal area of 24 sq ft. I have a horrible CdA of 12.4 . I have not easily measured the rolling resistance but I am sure it is on the poor side. These numbers agree pretty well with the EV calculator. The next step is to directly measure speed and temp so I can reliably get numbers on Wh/mile before I start improving the CdA and rolling resistance.