Monday, April 25, 2011

inaccurate display

Inaccurate display reading - display shows maximum of 3 bars when fully charged. Display shows
         0 hours on another machine

    1.  Illustration below shows 2 bars of charge level, 2 bars is approximately when the deck is shut off by
         the system while mowing. The batteries are fully charged and I got 70 minutes of mowing time before
         the deck shut off. The display dropped to 1 bar after 20 minutes and stayed there throught the entire
         mowing time.
        We could not find any connection that seemed not to make contact.

         We also had a display showing 0 hours when there actually were 6, it also displayed codes
         04A57 and 16A06. This unit would not start and run.
         We physically checked all connections and could not find any that seemed to not make contact.

       2.  We installed a new display with the same result. Changing the display is not necessary.

      3.  After changing the master controller (SEE NOTE IN NUMBER 4) we were able to re calibrate the
           accelerator by entering model number
           12242 which allowed us to access the controller with the Smartec programer. We then had a KO
            peddle code that we were able to bypass by pushing enter several times.The next screens to
           show were the calibration screens as shown in the Smartec manual.Changing the master controller
           was also not necessary.

      4.  By following the manual instructions the accelerators were successfully reprogrammed. The unit now
           operates as it should.    NOTE  To preserve the hours shown on the display the key should be cycled
           to on then to off rather quickly. To preserve the hours in the controller turn the key on and leave the
           key in the on position for 2 minutes. This needs to happen the first time the key is turned on with the
           new controller installed.

      5. We have not learned that to reset the display and the master controller to read battery voltage
          correctly, enter the "settings" menu and change the battery voltage setting either up or down and return
          the setting to the original number. Exit the program and the display should read correctly.

Friday, April 8, 2011

Battery Maintance and Testing

The following illustrations show proper battery maintenance procedures

This section has been modified December 2011. The modified information is in a separate section as follows: 

1. Never allow the water level to drop below the plates. To avoid this situation check the water level every 3
    to 5 cycles. When a pattern appears the water can be checked less and less often. Be sure to use the filler
   jug provided with distilled water. Low battery water seems to affect the charger function such as not
   allowing the green light to to indicate the charge cycle is complete and as a result the charger will continue
   the charge cycle indefinitely.

2. The charger should switch off at 20 hours but we have had chargers that in given situations will not turn the
    green light on to indicate the end of a charge cycle and they then will continue charging. In other situations
    these same chargers will charge and turn off as they should. If the charger is interrupted in any way while
    being connected to the Zeon, for instance a power surge or switching the charger off and then on, the
    charger will begin a new complete charge cycle and will probably overcharge the battery pack. To insure
    that the battery  pack does not get overcharged, remove the charger cable from the Zeon charging
     receptical after 20 hours of charge time. 
    If the Zeon is used withing 30 days do not recharge as long as the display shows 10 bars. If the Zeon is
    to be stored longer than 30 days the winter storage harness can be attached. If the storage harness is used
    the battery pack can then be charged every 45 days for the 20 hour period including disconnecting the
    charger after 20 hours.

3. The battery test procedures listed below are valid and can be used. We have found that batteries may
    have a short run time even if the voltage and specific gravity test good. It may be necessary to do a load
    test to verify the battery pack is producing a short run time. This can be done with a deep cycle load tester
    DO NOT use a cold cranking amp battery tester. The deep cycle test is done over a period of several
    hours depending on the battery rating and the capability of the tester. The load test can also be done with
    a volt meter attached to the battery pack while mowing. If the test is uninterrupted and the mower is ran at
    its capacity, the run time for the battery pack should be _???_ minutes. If the deck turns off at 42
    volts or less of battery voltage the controllers are operating as they should. If the voltage is above 42
    the batteries may not be the issue.

4. I don't have a good test procedure for the charger, I have not yet had one that failed to charge. Just be
    sure to unplug the charger from the machine at or about 20 hours and check the water level.

This is the original section with the charger and battery maintenance procedures.

1. Charge battery pack per the instructions in the owners manual. The hours of charge time varies, the pack
    will only be properly charged when the green light is lit as shown. The red light indicates that the charger
    has a 110V supply. The amber light indicates the charger is still charging and as long as the amber light is
    lit the battery pack may have issues but the charger sees the pack as insufficiently charged.

2. Check the electrolyte level periodically per the owners manual.
3. If electrolyte is not covering the plate, as illustrated below, or if electrolyte is below the fill level provided by
   the automatic fill level nozzle, water the cell using distilled water as shown in the 2nd illustration.

4.  Shown below is the recommended cell watering container that will automatically fill to the proper level

5.  It is recommended that the battery pack be fully charged before the battery pack is watered.
6.  Remove the negative post cable as illustrated.

7.  Remove the positive and negative battery cable connections and clean all corrosion from the cables and
     posts. Illustrations below show a corroded cable and cleaning method. If the corrosion is tight you may
     find it necessary to scrape the corrosion off.

8.  Tighten all battery connections as illustrated below.

The following illustrations show proper battery testing procedures

  1. If there is an issue of battery's not providing proper voltage or run time, the first step is to charge and clean and tighten the battery pack and connectors as shown above
  2. Test battery pack voltage as shown in the first illustration below (ON THE BATTERY POSTS) after 6 hours of rest to allow surface charge to dissipate.  Testing on the posts will eliminate battery connection except the large red wires between batteries.

    3.  A fully charged battery pack will read at least 50.9 volts. The illustration above shows 50.1 volts    which  is a partial charge.
    4.  Clean any and all corrosion from the battery cables and terminals if you have not already done so.
    5.  The red battery connecting cables can remain in place if they are clean.
         Notice the difference in test voltage on the number 1 battery when testing on the post compared to
         testing a potentially dirty cable.

   6.  Testing number 2 battery

    7. Testing number 3 battery. Notice the voltage increase.

    8.  Testing number 4 battery. Notice the voltage decrease

  9.  Test all battery ground connections by probing the positive post and the negative common post at the 
       bottom of the unit located between the two electric ZT drive trans axle units as illustrated by the following
       2 pictures.  If the batteries show full charge voltage (12.88), if all cable ends and battery surfaces are
       clean, and if the battery electrolyte level is proper, you may want to test the unit performance.

 Electrolyte specific gravity test  This test will determine if a single cell is below normal.
  10.  If the battery pack is low or if the unit was tested after the battery voltage test, recharge the battery
           pack until the charge lights show as below. This may take as long as 20 hours. Allow the battery to
           set idle for 6 hours to allow the surface charge to dissipate before starting the test below.


  11.  Pull enough electrolyte into the hydrometer to float the internal gauge.

    12.  Read and record the specific gravity registered on the gauge for each battery cell.

    13.  Compare your readings to the chart below. There are instructions included with the chart, please
           review the instructions to be sure you have done all the steps.

Before doing any testing, please follow all the necessary safety precautions. Below are a few safety precautions that will keep personnel safe:

•             Always wear protective clothing, gloves, and goggles when handling batteries.
•             Do not smoke near batteries.
•             Keep sparks, flames and metal objects away from batteries.
•             Use a wrench with a rubber handle when making battery connections.
•             The electrolyte is a solution of acid and water, so skin contact should be avoided.
•             Never add acid to a battery.

Test Procedures:
Below are the tests that should be performed to determine the health of the battery.

Visual Inspection
•             Inspect the battery’s case and check for cracks. If a crack is found no testing is
               needed since the battery was frozen.
•             Check for the overall cleanliness of the battery cover as it can be a good indication of
               battery neglect.
•             Inspect the battery terminals for corrosion. If corrosion is found on the terminals, they 
               should be wire-brushed prior to doing any charging or load testing.

Initial Data
•             Measure and record the specific gravities of all the cells when the battery first arrives. Pay 
              special attention to the electrolyte levels and note any cells that have low electrolyte
•             Measure and record the open-circuit-voltages (OCV) of all the batteries

Initial Recharge
•             Add distilled water to cells that are very low (near the group) or to cells that have exposed
•             Ensure that all the connections are clean and tight
•             If an automatic charger is used, allow the charger to terminate the charge on its own.

Data After Initial Recharge
•             Measure and record the specific gravities of all cells 4 to 6 hours after the recharge has
               been completed.
•             Measure and record the open-circuit-voltages (OCV) of all the batteries.
•             An increase in both specific gravities should be observed. The table below can be used to
              determine the state-of-charge (SOC) of the batteries.

 Table 1 – RE Series

SOC        Specific Gravity Open Circuit Voltage
                                Cell         2V           6V           12V        24V        36V        48V        72 V
100         1.265     2.110     2.110     6.33        12.66     25.32     37.98     50.64     75.96
90           1.246     2.091     2.091     6.27        12.55     25.09     37.64     50.18     75.24
80           1.227     2.072     2.072     6.22        12.43     24.86     37.32     49.73     74.64
70           1.207     2.052     2.052     6.16        12.31     24.62     36.94     49.25     73.92
60           1.187     2.032     2.032     6.10        12.19     24.38     36.58     48.77     73.20
50           1.165     2.010     2.010     6.03        12.06     24.12     36.18     48.24     72.36
40           1.142     1.987     1.987     5.96        11.92     23.84     35.77     47.68     71.52
30           1.119     1.964     1.964     5.89        11.78     23.57     35.35     47.14     70.68
20           1.096     1.941     1.941     5.82        11.65     23.29     34.94     46.58     69.84
10           1.072     1.917     1.917     5.75        11.50     23.00     34.51     46.01     69.00

Table 1
•             Should the batteries not reach the values in table 1 after the initial charge, than additional
              charging will be required depending on the level of discharge that the batteries were at
              when initially received.
•             If after the second recharge the battery’s specific gravities do not increase, than it is highly
              likely that battery is spent.

Tuesday, March 22, 2011

Sensor location and available reference voltage


1. Location of speed sensor harness plug, push the retaining clip to remove.

2. White/Red wire is 12 volts.

3. With Positive volt meter lead, probe the back side of the connector and NOT the wire insulation.
    Note: .035 mig weld wire was used to probe connector. 

      Note: Removal of speed sensor plug is not necessary for this test.

4. Reinstall speed sensor plug if you removed it.

5. It will be necessary to install a alligator clip lead from negative battery post to make the ground accessible with the weighted seat down to engage the seat switch (illustrated below, not shown in video). 

Weighted seat down in the operating position with negative leads attached (illustrated below)

6. Ground lead from voltage meter to negative battery terminal. Any and all BATTERY voltage tests should
    be grounded to the negative battery terminal as illustrated to ensure proper test results.

7. Key on

8. Voltage meter should read 12 DC battery volts minimum.

1.  The green lead is signal to controller voltage and will vary with the wheel motor speed.

2.  Voltage shown is approximate, if the voltage varies as the speed control lever is moved the sensor is
      probably operating correctly. Note that the voltages I was getting were not a smooth steady increase.

3.  When probing the green wire you are also checking the plug connections. If there is no
      voltage at  the green wire terminal, it may be a speed sensor failure or it may be a poor spade connection.  

4.  Notice the voltage shows in both the forward and reverse speed control lever positions.

5.  The white/green lead is also signal to controller voltage and all statements concerning the green lead will
     also apply here.

6.  The white/black lead is the sensor ground. Resistance should be zero between the lead and the negative
     battery terminal. The slight resistance shown here is from internal circuitry. Resistance is tested in ohms
     with electrical circuits off.

Testing a defective speed sensor
   1. A defective sensor will usually produce a 4A31 code. As of spring 2011 the most common cause of
       speed sensor failure has been metal sticking to the sensor from the failure of an internal thrust washer.
       If this is the case the entire electric wheel drive which includes the sensor needs to be replaced.

       A defective sensor will will also produce unpredictable variable voltages when the control arms are
        moved to the drive position. The neutral position may still show 12 reference volts . The illustration
        below shows a speed sensor that has metal particles attached from a thrust washer failure. Compare    
        these voltage results to the sensor test voltages above. The properly functioning system will show 12V
        as the controls are moved inward from the brake position and will immediately drop to 6 volts when
        the controls are moved forward or reverse. As the controls are pushed further into the driving positions
        the voltages will steadily increase or decrease as the controls are moved forward or backward.

 If you determine that the electric drive motor needs to be changed, refer to the illustrations 
      below for removal.
         1. Remove the speed sensor plug.

    2.  Remove electric drive mounting bolts.

    3.  Remove the rear electric drive guard.

    4.  Remove the large gauge electric cables noting their position, as well as the remaining two harness

    5.  Illustration below shows an electric drive operating properly as shown on the unit display and the
         volt meter. 


Safety brake failure
        Brake failed in the locked position (we saw on unit with this issue)
  1. Code 02A13 showing on display
  2. Verify that the controller or harness is not at fault by installing the electrical park brake release
  3. If the side in question will not roll easily and the opposite side does, replace the electrical traction drive unit.