Roper ZAP PK Xero (Sun Roper) Existence Log

 

L. David Roper
http://www.roperld.com/personal/roperldavid.htm

http://www.roperld.com/science/ZAPXebraPKRoper.htm

Books about cars, especially electric

Click to join Xebra_EV

Mileage Record

Modifications Made

Problems Fixed

Suggested changes for future ZAP Xebra PKs
ZAP Xebra PK review

Places in Blacksburg/Christiansburg, Virginia where Sun Roper has been charged.
(Always ask permission first.)
Virginia Tech YMCA Thrift Shop, Blacksburg
An official charging station was set up there on 28 June 2007.
Our Daily Bread, Blacksburg
B & K Truck, Christiansburg

New River Glass Shop, Christiansburg

 

 

Items To Do
(Items will be deleted when they are completed)
Find a way to use electric power to raise and lower the bed.

Unless stated otherwise all miles driven are actual miles, which are obtained by multiplying the Sun-Roper odometer miles by 0.86 according to a ZAP technician and my Garmin GPS.

Monthly log records of Sun Roper:

  1. April 2007 (Sun Roper decal, solar panel, newspaper article, Gottlieb front spring, PK parameters, voltage graphs, PowerCheqs installed, brake changes, bed liner inside, runaway Sun Roper, rear-view mirror, Virginia motorcycle drivers license)
  2. May 2007 (tailgate chains, drag coefficient, PakTrakr, wiper quit, glove-box expansion)
  3. June 2007 (PakTrakr current sensor, Woodward rear springs, side markers, home-made motor shield, O USE Helmet acronym, YMCA charging station)
  4. July 2007 (4th-July parade, winch plans, install solar panel)
  5. August 2007 (Steppin' Out, solar-panel ammeter, replacement axle)
  6. September 2007 (wheel drag, reverse problem & desulfator install)
  7. October 2007 (Woodward motor shield, hauling Sun Roper, emergency-brakes spring, River Roper kayak on Sun Roper)
  8. November 2007 (Sun Roper @ Energy Expo, driveway plug, battery tester, door liner)
  9. December 2007 (charger algorithm 42)
  10. 2008 (bad batteries, blown charger fuse, Woodward large display, new battery set, 84-volts conversion, Guest charger, broken emergency-brake cable, charger-fuse-holder bad, Woodward display with SD card, new radio, bad DC-DC converter, replaced PowerCheqs with BattEq, simple EV circuit, bad charger)
  11. 2009 (lithium batteries, 1C discharge curves, 95V charger/balancer, LiFePO4 batteries layout, PakTrakr for LiFePO4 batteries, auxiliary battery replaced, interlock bad, BattEq return for refund, antenna replaced, LiFePO4 batteries installed, bad LiFePO4 battery, batteries type comparison )
  12. 2010 (lithium batteries)

(Some of the problems mentioned in these daily logs have been fixed in later models.)

Analysis of logged Sun Roper trips.

Modifications Made

Before I got the PK, my dealer, Mark Higley, made the following modifications:

  • Made changes so that foot and emergency brakes do not cancel accelerator.
  • Installed LED lights in all but center headlight and the two backup lights.
  • Rhinolined the underside of the bed.
  • Replaced the gear-box oil plug.
Installed Gottlieb spring/shock in front. Ride is much better.
Replace 16" wiper blade with a 20" one. Now it covers my eye level.
Made changes so that emergency brake cancels accelerator, but foot brake does not.
Moved window cranks so that they do not gouge driver's and passenger's knee when fully opened and fully closed.
Cut off center mirror from the dome light and installed a mirror that glues to the windshield. It has a night-view lever.
Put small rubber bumpers underneath the two bed latches.
Put wood chocks on two sides of the 12-volts accessories battery to keep it from moving around in its case.
Had the inside of the bed Xtremelined, including the tops of the sides and tailgate.
Installed Powercheqs to keep batteries equalized. Later installed fuses that light an LED in the top housing if the fuse is blown.
Installed PakTrakr, including a current sensor.
Extended the glove box 3" below the opening.
Added two chains to hold the tailgate horizontal.

Using bicycle cable lock to lock down the bed when left outside not at home.

Installed net to hold items at front of bed.
Installed red side LED lights in place of reflectors in the back two sides.
Stopped shock squeaks by liquid wrench. Later installed zerked bolts at the bottom of the 3 shocks.
Installed an aluminum shield on the right side and bottom of the motor to keep water and dirt from being splashed into it.
Replace convex mirror on driver's side with a flat one.
Put a Radio Shack toggle switch on the black wire of PakTrakr to make it easy to reset it.
Installed the solar panel as a roof over the bed.
Got "Winning Blue" touch-up paint from Mazda to touch up some scratches.
Installed Woodward motor shield in place of the one I devised.
Installed 72-volts Battery-Life-Saver desulfator.
Installed Woodward large display for PakTrakr.
Installed 12-volts Battery-Life-Saver desulfator for 7th battery.
Installed BattEq for 6 batteries after uninstalling the 5 PowerCheqs.
Installed 5 switches on for the last 5 batteries for the BattEq.
Installed a windshield washer.
Uninstalled BattEq because of a manufacturer's recall.
Replaced the 7 Discover EV12A-A batteries with 26 HiPower LiFePO4 batteries.

Problems Fixed
Wiper moter died. Mark Higley sent me another one.
Brake reservoir cap would not fully close. Mark Higley sent me another one.
Moved window cranks so that they do not gouge driver's and passenger's knee when fully open and fully closed.
Replace 16" wiper blade with a 20" one. Now it covers my eye level.
Top of dash cover has pulled away from the windshield about 0.25". Managed to push most of it back using a rubber tube.
2nd cigarette lighter had been removed in order to install the green emergency button, which is not needed on my 72-volts-ignition PK. Mark Higley sent me a 2nd lighter to put there. I installed it through the vestigial power switch, so that the 2nd lighter can be turned on and off. I use it for a powerful directional fan to keep the driver cool at stops.
The fuse box has the windshield-wiper-fuse location incorrectly marked. It is the 2nd one from the left.
Two of the four boots on the axle had small slits in them. I used Black Rubber Sealer to seal the slits to try to stop the grease leak in one of them. That did not work, so I put tire patchs on slits in two CV boots. That also did not work. Mark Higley is getting me a new boot.
The F/N/R switch came loose. It is a good idea to tighten the knurled ring around it periodically.
Replaced driver's door liner.
Replaced bad charger fuse holder with a new one from Advance Auto.

Mileage Record for First Two Months (April & May 2007) of Driving

Date Day Driving Number Daily odometer miles traveled Daily actual miles traveled Daily kWh to charge Daily miles/kWh Daily cost @ $0.075/kWh Total odometer miles Total actual miles traveled Total cost to date Daily-cost/mile Daily equivalent mpg by energy Calculated Range @ 9.75 kWh charge
Totals   836 719 255   $19.10            
Average   18.6 16.0 5.66 2.82 $0.42       $0.028 99 27
2-Apr-07 1 5 4.3 2.13 2.02 $0.16 136 4 $0.16 $0.037 73 20
3-Apr-07 2 32.5 28.0 11.05 2.53 $0.83 141 32 $0.99 $0.030 91 25
4-Apr-07 3 8.4 7.2 2.91 2.48 $0.22 173 39 $1.21 $0.030 89 24
5-Apr-07 4 36.4 31.3 10.69 2.93 $0.80 182 71 $2.01 $0.026 105 29
6-Apr-07 5 27.1 23.3 9.38 2.48 $0.70 218 94 $2.71 $0.030 89 24
7-Apr-07 6 9.8 8.4 4.17 2.02 $0.31 245 103 $3.02 $0.037 73 20
9-Apr-07 7 30.1 25.9 8.58 3.02 $0.64 275 128 $3.67 $0.025 109 29
10-Apr-07 8 8.1 7.0 2.67 2.61 $0.20 283 135 $3.87 $0.029 94 25
13-Apr-07 9 27.9 24.0 9.39 2.56 $0.70 311 159 $4.57 $0.029 92 25
14-Apr-07 10 28.7 24.7 8.62 2.86 $0.65 340 184 $5.22 $0.026 103 28
15-Apr-07 11 15.7 13.5 5.21 2.59 $0.39 356 198 $5.61 $0.029 93 25
16-Apr-07 12 10.5 9.0 3.48 2.59 $0.26 366 207 $5.87 $0.029 93 25
17-Apr-07 13 8.3 7.1 3.2 2.23 $0.24 374 214 $6.11 $0.034 80 22
18-Apr-07 14 34.2 29.4 9.55 3.08 $0.72 409 243 $6.83 $0.024 111 30
19-Apr-07 15 22.7 19.5 6.66 2.93 $0.50 431 263 $7.33 $0.026 106 29
20-Apr-07 16 12.2 10.5 3.98 2.64 $0.30 443 273 $7.63 $0.028 95 26
21-Apr-07 17 24.3 20.9 7.08 2.95 $0.53 468 294 $8.16 $0.025 106 29
23-Apr-07 18 22.6 19.4 7.01 2.77 $0.53 490 313 $8.68 $0.027 100 27
24-Apr-07 19 24.5 21.1 7.02 3.00 $0.53 515 335 $9.21 $0.025 108 29
25-Apr-07 20 18.1 15.6 5.64 2.76 $0.42 533 350 $9.63 $0.027 99 27
26-Apr-07 21 31.7 27.3 8.66 3.15 $0.65 565 377 $10.28 $0.024 113 31
27-Apr-07 22 16.7 14.4 4.99 2.88 $0.37 581 392 $10.66 $0.026 104 28
28-Apr-07 23 28.3 24.3 8.67 2.81 $0.65 610 416 $11.31 $0.027 101 27
29-Apr-07 24 9.5 8.2 3.25 2.51 $0.24 619 424 $11.55 $0.030 90 25
30-Apr-07 25 21.1 18.1 6.25 2.90 $0.47 640 442 $12.02 $0.026 105 28
1-May-07 26 15.2 13.1 4.7 2.78 $0.35 655 455 $12.37 $0.027 100 27
2-May-07 27 32.8 28.2 8.87 3.18 $0.67 688 484 $13.04 $0.024 114 31
3-May-07 28 29.2 25.1 8.21 3.06 $0.62 717 509 $13.65 $0.025 110 30
4-May-07 29 9 7.7 2.89 2.68 $0.22 726 517 $13.87 $0.028 96 26
6-May-07 30 2.1 1.8 0.71 2.54 $0.05 729 518 $13.92 $0.029 92 25
7-May-07 31 17.2 14.8 5.67 2.61 $0.43 746 533 $14.35 $0.029 94 25
8-May-07 32 6.7 5.8 1.89 3.05 $0.14 752 539 $14.49 $0.025 110 30
9-May-07 33 10.1 8.7 3.31 2.62 $0.25 763 548 $14.74 $0.029 94 26
11-May-07 34 11.7 10.1 3.94 2.55 $0.30 774 558 $15.03 $0.029 92 25
12-May-07 35 16 13.8 4.81 2.86 $0.36 790 571 $15.39 $0.026 103 28
14-May-07 36 20.4 17.5 6.41 2.74 $0.48 811 589 $15.87 $0.027 99 27
15-May-07 37 10.8 9.3 3.29 2.82 $0.25 821 598 $16.12 $0.027 102 28
16-May-07 38 36.9 31.7 9.78 3.24 $0.73 858 630 $16.85 $0.023 117 32
17-May-07 39 6.4 5.5 2.22 2.48 $0.17 865 635 $17.02 $0.030 89 24
25-May-07 40 7 6.0 2.42 2.49 $0.18 872 641 $17.20 $0.030 90 24
26-May-07 41 13.7 11.8 3.82 3.08 $0.29 885 653 $17.49 $0.024 111 30
28-May-07 42 28.1 24.2 7.61 3.18 $0.57 914 677 $18.06 $0.024 114 31
29-May-07 43 9 7.7 2.81 2.75 $0.21 923 685 $18.27 $0.027 99 27
30-May-07 44 27.2 23.4 7.04 3.32 $0.53 950 709 $18.80 $0.023 120 32
31-May-07 45 11.6 10.0 3.99 2.50 $0.30 961 719 $19.10 $0.030 90 24
30-Jun-07 46 36.3 31.2 9.52 3.28 $0.71 998 750 $19.81 $0.023 118 32

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The asymptote is 2.83 miles/kWh. This could be thought of as batteries conditioning and driver conditioning combined.

The asymptote is 3.62 miles/kWh. This should be reasonably independent of driver conditioning. Of course, it does depend on how the driver drives; I tend to drive full throttle, but I do coast at 40-45 mph down hills and up to stop lights and signs as much as possible. Note that all three fits are very similar. It appears that the miles/kWh would improve if I drove more miles per day; that is, the motor would "like" to have more energetic batteries. Some of the days had opportunity charging.

Data and quadratic fits to data for miles/day <= 10, 10 < miles/day < 20 and miles/day >= 20.

Range versus driving day calculated at 9.75 kWh useful battery storage.


Monthly miles/kWh versus months driven.
The solar panel was in operation for the last week of month 4 (July 2007).

 

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Things I would like to have changed on the PK:

  • Left mirror flat instead of convex.
  • Center mirror with night lever attached to the windshield instead of to the roof light.
  • Windows roll all the way down below the sill.
  • Door of charging plug open upward to form a rain deflector, instead of frontward.
  • Bigger glove box that extends below the lip.
  • Storage pockets in the lower portions of the doors, on the front-wheel well and on the walls behind the two seats.
  • Glove box that extends downward below the box sill to keep items from falling out.
  • Window handles that point upward and to the front when windows are fully open and fully closed.
  • 20" or longer wiper blade.
  • 2" longer prop for the hood.
  • kW meter & kWh readout in dash.
  • Paint under the bed sides hinges and tailgate hinges.
  • Undercoat the bed and frame.
  • Electric system operates when foot brake is depressed, but not when emergency brake is on.
  • LED lights as much as possible.
  • LED side markers instead of reflectors.
  • Adjustable softer springs/shocks on all three wheels.
  • Electric lift option for the bed.
  • Wire the contactors to fix the contactors problem.
  • More rigorous quality control.
  • Battery equalizers as standard feature or an option.
  • Include a paint touch-up kit.
  • Make cab a foot wider so that the brake and accelerator pedals are in a more normal position.
  • Make cab a foot deeper so that there is more variability in seat position and seat-back angle.
  • Repair manual telling how to take the vehicle completely apart in proper sequence.

Books about cars, especially electric

  • The Electric Car: Development and Future of Battery, Hybrid and Fuel-Cell Cars by Michael H. Westbrook, 2005.
  • The Electric Vehicle and the Burden of History by David A. Kirsch, 2000.
  • Taking Charge: The Electric Automobile in America by Michael Brian Schiffer, 1999.
  • Electric and Hybrid Vehicles: Design Fundamentals by Iqbal Husain, 2003.
  • The Essential Hybrid Car Handbook: A Buyers Guide, Nick Yost, 2006.
  • Plug-in Hybrids by Sherry Boschert, 2006.
  • Forward Drive: The Race to Build “Clean” Cars for the Future by Jim Motavalli, 2001.
  • The Hype about Hydrogen by Joseph J. Romm, 2005.
  • Lives Per Gallon: The True Cost of Our Oil Addiction by Terry Tamminen, 2006.
  • Internal Combustion: How Corporations and Governments Addicted the World to Oil and Derailed the Alternatives by Edwin Black, 2006.
  • Traffic Safety and the Driver by Leonard Evans, 1991
  • High and Mighty: SUVs: The World's Most Dangerous Vehicles and How They Got That Way by Keith Bradsher, 2004.
  • Electric Dreams: One Unlikely Team of Kids and the Race to Build the Car of the Future by Caroline Kettlewell, 2004.
  • Carfree Cities by J. H. Crawford, 2002.

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