Roper ZAP PK Xero Existence Log for June 2007

L. David Roper

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PakTrakr current sensor, Woodward rear springs, side markers, home-made motor shield, O USE Helmet acronym,
YMCA charging station

1 June 2007

I drove the furthest today on a single charge: 31.2 miles. I could have driven at least 5 more miles. The low-battery light was coming on every now and then, but not steadily. This was in some rather steep hills of Blacksburg and Christiansburg VA. The voltage after stopping for a while was 71.5 volts.

2 June 2007

Reinstalled a new PakTrakr (the old one always registered 100% SOC) and installed the current sensor for it:

Note the current sensor on its short bus bar at the right in front of the orange cap and behind the red wire. The PakTrakr is to the left of the current sensor near the frame. The two wires go under the frame and through a hole I drilled in the cab with a grommet in it to protect the wires. Without going into details I learned that my PakTrakr display needs to be exchanged for one with later firmware, since I have a 400-amps current sensor and apparently my display is calibrated for a 300 amps current sensor. When the current sensor is installed the display shows battery current and calculates power in kilowatts. I decided to put the remote outside and below the frame, so that I can view that it is working ok (flashing light) without lifting the bed:

The tray over the front of the batteries has to be removed when one wants to get to five of the battery poles. I put wing nuts on the two bolts to make it easier. If one only needs to get into one side, the bolt for that side can be removed and the tray swung backward:

3 June 2007

Drove to church in a light rain. The brake and motor-hot warning lights partially showed, apparently due to the wet weather. The PakTrakr is now showing SOC; however, it appears to be erratic. Ken Hall of PakTrakr is looking into the situation.

4 June 2007

Drove to the Montgomery County Hospital for blood tests through back road with steep hills. Tested PakTrakr SOC display (V, SOC%):

(78.5, 100), (72.2, 95), (69.8, 82), (75.6, 78), stopped 30 minutes, (77.0, 100), (75.3, 82), stopped 30 minutes, (76.0, 100), (70.4, 73), (65.4, 69), end of run of about 13 miles, 30 minutes later (75.4, 86), about an hour later (75.6, 91 and 86 a few seconds later). PakTrakr needs to be reprogrammed for the Discover batteries; Ken has agreed to send me another remote programmed for the Discover EV12A-A batteries.

5 June 2007

Yahoo/Xebra-EV post indicates a possible grease-leak problem at a CV joint near a wheel. I looked and I have the same problem at the right wheel:

There was more grease on the brake lever at the right, which I removed. I do not detect any damage to the boot, but I will inspect it closely when I take the wheel off to change the springs to the Woodward springs. The left side looks clean. I will keep a watch on this. I will have South Main Auto look at this and at a squeak in the front Gottlieb spring that they installed.

The Woodward adjustable springs for the rear came in. One of the six set screws was missing or got lost when I emptied the containers holding them. I had trouble getting the plastic sleeves off the end of the shocks by banging on them as shown in the video that came with the springs, so I got them off by cutting them with a knife and pulling them off with pliers. I got one on and the other one ready for tomorrow when I will try to get a set screw at the local hardware store. Had to take the spare tire out of its holder in order to be able to lean the left shock/spring backward to change the spring.

6 June 2007

Got the set screw. Finished getting the Woodward springs on the rear. Norm's video was very helpful in doing the job.

This is the first time I have ever done something like this (at age 71.5). It gives me confidence to do more work on Sun Roper.

Had to take fender off of front wheel to grease the zerk above it. It is difficult to get the bolts back in the two holes; so I used silcone rubber sealant to help hold them. It took much grease.

The steering wheel became easier to turn after I greased the zerk.

Drove to a Blacksburg Community Band concert at Warm Hearth. I got to test out how to judge the PK feel at skidding going around a curve on my way. I took a right-hand curve too fast and the rear wheels started skidding to the left, but the front wheel did not skid. I did not feel a lean or the left rear wheel leaving the ground. I was able to stop the skid with the vehicle about six inches into the left lane. I felt mostly in control, but now know the feel when the speed is too fast for a curve.

Got another PakTrakr remote and display programmed for the Discover EV12A-A batteries. They appear to be working ok.

I am now only charging over night, since I am able to travel anywhere I want to go in the Blacksburg and Christiansburg area without opportunity charging.

7 June 2007

Installed red side LED marker lights powered from the tail lights.

Then I tied the wires with gree ties to bed supports:

The wires for the rear lights had been hanging down since I got the PK. Now they are up out of the way.

8 June 2007

I have the PakTrakr  installed and working in Sun Roper (Discover EV12A-A batteries ). I also have the 400-amps  current sensor  attached to it and encircling a short bus off of one of the batteries.

It has a two-line LCD display:

  • Top graphic display:
    • Pack SOC
    • Individual battery voltages
    • 30 day lowest pack voltage
    • 30 hour average pack voltage
    • 30 minute average pack voltage
  • Bottom digital display:
    • Pack voltage
    • Pack SOC
    • Individual battery voltages
    • Temperature at the location of the remote
    • Alerts (problems detected by remote) See below for abbreviations.
    • kilowatts in/out
    • amperes in/out of pack
  • Alerts abbreviations:
    • Chk Watr (low water likely)
    • Chrg Bat (pack imbalance)
    • Failing (battery is failing)
    • Damaged (battery is shorted or damaged)
The SOC is based on the battery voltage integrated over time. The display must be calibrated before shipping to fit the batteries being used. Send the battery specs when ordering. Since the voltage rises after a vehicle is stopped, the SOC will also rise after a vehicle is stopped. So this SOC display is not very accurate. I use it in conjunction with the odometer to get a measure of the SOC.

I usually keep the top graphic display set on SOC, since the accuracy is well enough represented by the bar graph.
I usually keep the bottom digital display set on kW.
I have noticed the following for the kW display:
  • When accelerating maximally from rest the kW display can get as high as 18 kW, but only fleetingly, 15 kW is more usual.
  • When accelerating at speeds higher than 30 mph the kW display is usually between 5 and 6 kW.
  • When coasting and at rest with the vehicle electric system on the kW display is 0.1 kW.
  • Of course, when the vehicle electric system is off the kW display is at 0 kW.
  • When charging the kW display is at -1.0 kW in the early stages.
So, I conclude that the power curve rises fast to a narrow peak of 18 kW at about 10-15 mph and then falls fairly rapidly to an asymptote of about 5 kW. If I could find a level road around here I would try to draw a graph of kW vs speed.

Next I hope to hook up the Automatic Logging Serial Interface  to record the PakTrakr data into a computer file.

The steering wheel started squeaking today. I will take it apart and try to stop the squeak tomorrow.

9 June 2007

Put an aluminum shield below the motor to keep items from being kicked into it by the rightwheel:


I used three velcros: two 2" x 1.5" beside the motor plate and one 3" x 1.5" below the motor plate.

I used the PakTrakr current sensor to plot rough curves of power vs speed and vs rpm:

To calculate rpm I used the gear ratio 4.5:1 given by and 19" for the wheel diameter.

I drove to several places in Christiansburg today and later drove to downtown Blacksburg. The Sun was shining brightly and the temperature was above 85 degrees. I saw that I was not going to be able to make the 3 miles home at a decent speed. The PakTrakr showed almost down to zero SOC. So I went to the VT YMCA Thrift Shop and got permission to charge for an hour. The 1.05 kW got me home by not going full speed. When I told the director of the VT YMCA, she said that she will call The Roanoke Times and tell them that the charging-station sign will be put up at the VT YMCA within the next two weeks. Later I tore up a large wooden picnic table and used Sun Roper to haul it to my dumpster. Today was my farthest driving day: 40.7 miles. I bought a wheeled pump jack for future work on Sun Roper.

Again I forgot to put on the emergency brake, this time in our relatively flat driveway. As I was getting out of the PK it started rolling backward. So I have devised an acronym to say every time I get in and out of the PK: OUSEH or Oh, USE Helmet, meaning:
O = Odometer, reset it at the beginning or end of each day.

U = Unplug power cord from vehicle or plug it in

S = Seat belt, fasten it

E = Emergency brake, set it at every stop and release it before driving (now I cannot drive with it set)

H = Helmet, put it on or take it off

I bought a one-ton wheeled pump jack and two adjustable vehicle stands for working on Sun Roper. Later, for Fathers' Day, my daughter, Tamra, gave me a 2.5 ton pump jack, so I will donate the one-ton jack to the HfHNRV ReStore for resale.

I ordered a "Winning Blue" paint touch-up kit from a Mazda dealer to use for Sun Roper.

10 June 2007

I drove to a Citizens First picnic up a steep gravel tracked road about a mile. I parked going up a hill on soft grass in such a way that I had to turn the front wheel about 15 degrees to get out. When I left the picnic I could not get the PK to go; the low torque at zero rpm would not do the job. I backed up and then slightly forward a few times until I could reduce the forward slope enough for the PK to move forward. A valuable lesson was learned: park on a level or down hill spot, especially on soft ground at an angle to the way to get out.

11 June 2007

  • We got a large picnic table and six chairs from Smith & Hawken today that came in a huge amount of heavy cardboard. I hauled a well rounded load held on by bungee cords to the cardboard recycle bin. I bought two vehicle jacks for future work on Sun Roper.
  • The Roanoke Times published a commentary I wrote about gasoline prices today.

12 June 2007

Took Sun Roper to South Main Auto (SMA) to have a new rubber boot put on the left CV joint that is leaking grease. I will get an extra boot for the future. I took my bicycle and rode 5.5 miles home while they were working on SR. They found another boot with a cut in it, the one next to the differential on the left. They were not sure how to take the axle out. Does one side come out first? They do not want to damage the axle, so are asking for instructions from ZAP about how best to replace the leaking boots. (One can ride bicycles all over Blacksburg without being in much car traffic.)

Our Virginia Legislature delegate James Shuler told me that he is working with DMV to make regulations about not requiring a motorcycle license to drive a three-wheeled vehicle that is enclosed and has seat belts and a steering wheel.

13 June 2007

I rode my bicycle 5.5 miles back to SMA to bring SR home until instructions are provided on how to remove the boots. The boot to the left does not have any grease on it, just a cut. I bought some black rubber sealant to put on the cut: 

The right back shock/spring is squeaking badly. Norm Woodward is sending me bolts with a grease zerk on them to put on all three shocks to combat the sqeaking problem. He is also sending me two spring upgrade kits to make the ride better and quieter. I ordered an impact wrench, so that I do not have to borrow one to work on the suspension.

15 June 2007

I put some Liquid Wrench on the lower shock mount and the squeak went away. I drove a friend to lunch and he commented on the much better ride with the new rear springs.

16 June 2007

I got the rubber bumpers and the zerked bolts from Norm Woodward to make his back springs quieter and have a better ride.

I drove in the evening to the weekly classic car display at K-Mart in Christiansburg to show off Sun Roper. Many people came by to talk about it. One guy stayed near it the whole hour I was there. One man who works at Virginia Tech Transportation Institute talked at length with me. He said that he would like to get a PK and wants me to bring Sun Roper to VTTI for the researchers there to exam it. He also wants me to bring my 2005 Prius with CANView on it for observation.

17 June 2007

I installed the Woodward rubber bumpers on the rear shocks and one of the bolts with a grease zerk on them at the bottom of the right rear shock. One has to move the chassis up and down with the pump jack to get the new bolt in. I could not get the old bolt off on the left side. I put some WD40 on it to try to loosen it up, so that I can try later.

18 June 2007

  • Hose House in Christiansburg told me that they would do the hose work if I could find hydraulic jacks and a 12-volts pump for raising the bed. I checked the hydraulic jacks in the Tractor Store and none were small enough. I think that an electric screw is what is needed.
  • New River Glass in Christiansburg took out the convex thin glass in the driver's mirror and replaced it with a flat glass mirror for $20. The glass shop told me that I could recharge there any time. Here is a picture of Sun Roper in the glass shop.

19 June 2007

Items for today:

  • I got a Cummings electric impact wrench today, so I took off the right rear wheel and wiped the grease off of the rubber boot; then I put the wheel back on and moved the vehicle enough to rub the grease off of the other side of the boot. I did not detect any cuts. Perhaps the grease got on there in manufacturing. I will watch it closely for more grease in the future.
  • My Virginia Legislature delegate, James Shuler, got the following message from the DMV:
    Three wheeled motorcycles (sidecar/tryke) are becoming very popular.  Our law states that any vehicle with three wheels or less in contact with the ground is considered a motorcycle.  These developments in vehicle structure and utility have presented some challenges.
    DMV staff is currently revising our test for these vehicles.  The vehicle you referred us to, in particular, is more a car than a motorcycle because it is completely enclosed with seat belts and a hard top.
    We are handling what we can administratively. In addition, DMV staff is evaluating whether a change in the State Code of Virginia is needed. So, in answer to your question, it may be a mix of both administrative and legislative changes.

20 June 2007

  • I drove to and around Christiansburg today, with about an hour of recharge there. Then I drove back to Blacksburg and had lunch at Our Daily Bread, where the owner, Karen, let me charge for another hour while I had lunch. Total for the day was 43 actual miles.
  • After cleaning the grease off of the CV boot yesterday, I was able to see a 1/4" slit at the outside edge of the boot right beside the metal clamp. I used black rubber sealant to try to seal it. I will look at it again tomorrow to see if it worked. The first picture below shows the grease bubbles that came out of the slit while I was driving. The second picture shows the attempted repair.

It did not work, so I am going to get a tube patch kit and try to patch the slit.

21 June 2007

  • I drove to the Green Infrastructure Fair today in Christiansburg where I had a booth on Cool Cities and hybrid and electric vehicles. While there a green engineer at Virginia Tech said that he wanted to get a PK. So I e-mailed him to give him information he requested.
  • The windshield glass is rather low quality. When I drive into the Sun, as I did this evening, the glass is very cloudy.

22 June 2007

Dale Schutt and Steve Oliver came by to help me rewire the forward and reverse contactors. We mistakenly did not exchange the M and L cables, so, when I got in the vehicle after the job, it went backward when it was supposed to go forward and vice versa. We did the M and L cables exchange and it then drove ok.

23 June 2007

  • I drove to the Blacksburg Farmer's Market where many people gathered around Sun Roper to ask questions.
  • I put half of a 1" circular tire patch on the slit on the right CV boot. See picture below.
  • I drove to the classic car display at K-Mart in Christiansburg. About 15 people talked with me at length about Sun Roper. Another two people stopped me at Lowes afterward.

The patch appears to be holding in the grease.

24 June 2007

I got the PakTrakr ES1R Automatic Logging Serial Interface to download data to my Tablet PC today. However, the power and current readout give nonzero values when it is attached to the PakTrakr, but not when it isn't. I am communicating with Ken Hall at PakTrakr about this problem.

26 June 2007

  • Mark Higley told me that the frame for the solar panel is on its way to me. I hope to get it on Sun Roper before the Blacksburg 4th of July parade.
  • I got 2 large round LED stop lights to attach at the top of the back solar-panel frame. I saw them on Erwin Gogolz's PK.
  • I put a round 1" tire patch on the slit in the left CV boot near the gear box. It doesn't look as neat as the patch on the CV boot near the right wheel. The boots near the gear box apparently have no grease in them; it appears that they are just to keep dirt out, so maybe the crude patch will work. The black rubber sealer I tried previously did not work.
  • I got two old linear actuators used for satellite dishes from Steve Oliver, but both are too long for a PK bbed lift. I am looking at the linear actuators of Nook Industries to see if one of them will work

27 June 2007

  • Took some picture of Sun Roper at night; see below. I have had some problems with the front and back LED lights staying in contact. I have used duct tape to hold some of them in place.
  • At the Blacksburg Farmer's Market a young lady asked me about the Xebra. She said that she has a friend who is interested but,
    after looking at, has decided to wait for the next better ZAP electric car. I asked her if she had ever heard about vaporware. After some discussion she took my e-mail and said that she would have her friend contact me.
  • I changed the gear oil at about 1400 odometer miles (0.86 factor for real miles). This time I used 100% Lucas Heavy Duty 80/90W oil. I bought a funnel from Advance Auto to make it easier and mess-free to fill the gear box with oil. It has a cap on the top and bottom and a blue valve in the middle; see picture below. The PK maintenance says to use 6-8 oz; I put 7.5 oz in the funnel, which was more than needed to cause oil to drain out of the overflow hole. Next time I will put 7 oz in it.



28 June 2007

The charging-station sign made by Mark Higley was installed at the Virginia Tech YMCA Thrift Shop and Community Center today:

The red arrows show the final sign location and the two plugs.

30 June 2007

For the first time I drove Sun Roper off of the Blacksburg/Christiansburg plateau down from Main Street (about 2100 feet elevation) 600 feet into Ellett Valley (about 1500 feet elevation) and back, about 6.5 miles, through winding roads with sharp turns. Of course, he coasted all the way down. His speed never got lower than 18 mph coming back up Deercroft Drive and Nellies Cave Road, except for the stop sign at the junction of the two roads.

Comparison of the first three months of driving Sun Roper.

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