SOC-Meter Assembly/Test PROBLEMS

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garygid

Well-known member
Joined
Apr 21, 2010
Messages
12,469
Location
Laguna Hills, Orange Co, CA
1. Carefully inventory your parts before you start building.

BIG Parts:
1. Box (with lid, and 4 screws inside)
2. OBD cable (6' or possibly 9')
3. Tube of RTV Sealer ("glue")
4. Roll of Electricians Tape
5. Box with AVR-CAN board & Display (check color)
6. Bag of small Parts
7. Instructions: Wiring Diagram, Hole Template, and possibly more

Small Parts:
1. Switch, toggle, On-Off-On, single pole (Power Switch)
2. Switch, toggle, On-Off-On, double pole (CAN-Selector)
3. Two Push-buttons: Red and Black cap (user input)
4. Zener Diode, 5.1v, 1 watt
5. Shrink Tube, thin, about 1"
6. 9-pin "D" connector, female, solder-style pins
7. Housing for crimp-pins, one 4x2, one 6x1
8. Six wires with crimp pins, about 3" (Green, Red, Orange, Gray, and two Black)
9. Four wires, about 3" (Red, Black, White, Gray)

------------------
 
Test Procedure:
(If a trial fails, STOP and fix it.)

1. Turn the LEAF completely OFF
2. Set both toggle switches in "center" position (Power OFF, No CAN)
3. Trial: Plug OBD cable into LEAF, being prepared to unplug QUICKLY. Watching the Display, nothing should happen.
4. Trial: Observing Display, turn SOC's Power Switch ON for one second and back off. You should have seen "0000" on the display.
5. Trial (Set Display Baud Rate):
Holding down the two Push-Buttons (PBs), turn the SOC ON again, releasing the PBs after 4 seconds. Watch for the Firmware Version (like "F1.07") to display. Possibly "strange characters" will appear this one time on the display as the Display's baud rate gets set. The display should end with "----" showing.
6. Trial: Power OFF, and ten ON again. There should be no "strange characters" this time, the "F1.07" should show for a second, and the Display should show "----".
7. Trial (PB test): Press the Black PB and the Right "-" should "jump up". Press the Red PB and the Left "-" should "jump" up. Turn SOC Power switch OFF (center position).
8. Trial (Auto-Power): Turn the SOC Power switch's toggle down (Auto-Power Mode). Nothing should happen.
9. Trial: Foot OFF LEAF's brake, and "fob" nearby, press LEAF's Power button once to enter ACC1 mode. The Nav screen should light up, but the SOC Meter should do nothing.
10. Trial: Press the LEAF's Power button a second time to enter ACC2 mode. The SOC Meter should come ON automatically, ending with "----" displayed. This means that the SOC Meter is waiting to detect an active CAN bus.
11. Trial (select a CAN buss):
Switch the SOC Meter's CAN-Select toggle switch "up", to connect the Car-CAN buss to the Meter's input. The "----" should disappear quickly, within a second, and " 0.0" should be displayed because the Car-CAN buss does not have any SOC-messages to detect and display.
12. Trial: Switch the CAN-Select "down" to select the EV-CAN buss. You should continue to see 0.0 until the first SOC-message is detected (up to about 6 or 10 seconds), then a percentage should appear (something like " 80.7", depending upon your LEAF's State Of Charge).
13. Trial: Tap the Black PB and the display should change format to show the "raw" SOC-message data (like " 282" at 100.3 percent or " 0" at 0.0 percent).
14. Trial: Tap the Black PB again to "flip" back to the percentage format. At this point, the Red PB does nothing.
15. Trial: Turn the LEAF OFF, and the SOC Meter should go Off.
 
Normal Operation:
(Do the Test Procedure first.)

1. The normal operating position of the two toggle switches is "down", to select Auto-Power mode and the EV-CAN buss.
2. The SOC-Meter's Always-ON power mode (Power switch “up”) can be useful DURING Charging. But, remember to switch back OFF or to Auto-ON so that the LEAF's 12v battery will not become depleted.
3. Normally, using Auto-ON, there should be no need to disconnect the OBD cable unless you take the LEAF in for Service. Then, it might be best to remove the SOC-Meter from the car.
4. CAREFULLY route the OBD cable so that it is IMPOSSIBLE for the cable to interfere with your feet or the Go-Faster and Go-Slower pedals.

Problems
If there are any problems, please check this thread, and post here to ask questions.
 
Misc Problems and Solutions:

1. Missing Part in Kit:
Double-Check, and if not found, please PM me.

2. Hole Template (1b) has wrong size hole for the Display:
Download version "1c" which has a 1/2" x 25/16" hole,
and contains dimensions for some hole centers.
 
So I went down the street to see if my neighbors CNC could be pressed in to service. He informed me that he would be very hesitant to use it on a plastic case since there is a good risk of it fracturing the case...
Oh well.

garygid said:
2. Hole Template (1b) has wrong size hole for the Display:
Download version "1c" which has a 1/2" x 25/16" hole,
and contains dimensions for some hole centers.
 
No problem, and thanks for checking.

I cut the "rectangular" (with 1/8" radius corners) hole (for the LED Display) in some Boxes today. Some will pay a bit extra to have their Kit's box with this hole in it.

It went quite well, once I got set up ... except for one box that now has a 1/4" wide slot headed out into never-never land. :D
 
One change I can suggest for your instructions is to inform the builder what the location of the wiring colors on the switches will indicate, so the builder can install them the right way up to correspond with the various instructions telling him to move the switches into "up" and "down" positions.

So in the case of the power switch Green would be up = "on" and Red would be down = "auto power". For the Can Select (aka DPDT) switch the side with the Green/Black & White/Black wiring would be down = "EV CAN".
 
When the toggle handle is down (as Auto-On for Power), the switch's center
Contact is connected to the UPPER contact (away from the toggle end). So, the drawing is correct.

Do you believe otherwise?
 
garygid said:
When the toggle handle is down (as Auto-On for Power), the switch's center
Contact is connected to the UPPER contact (away from the toggle end). So, the drawing is correct.

Do you believe otherwise?

Oh. OK. No I get it. I guess I just needed to have that pointed out to me. I didn't realize the drawing showed the orientation.

You've seen my other issue with the SOC data I'm getting?

I have another couple of data points:

66.5% 187 raw
66.1% 186 raw
65.8% 185 raw

Once round the block in my complex appears to cost me 1 increment of the raw number! At this rate I should be down to turtle after another 185 goes! :lol:
 
garygid said:
Yes, it seems correct for 1/3 down in Old-Bars.

And, Good Work.

Thanks. I thought it might be old bars/new bars.

I drove around the block another couple of times:

66.5% 187 raw
66.1% 186 raw
65.8% 185 raw
65.4% 184 raw
65.1% 183 raw
64.7% 182 raw

I could do this all night!
 
mwalsh said:
I could do this all night!
Let us know how it goes in the morning ;-)

One thing that would be great to figure out is the usage on the freeway at different speeds. Also up & down certain hills (we will get the real regen efficiency). Still waiting for my LCD display ...
 
This raw "SOC" value is clearly NOT actually THE remaining-energy number, but only related to it.

The SOC-Meter's displayed "percentage" value is just the raw value as a percentage of 281 ((raw * 100) / 281), without any fancy mapping.

Since MANY drivers have noted reduced "mileage" during the first bar, it is clear that this "SOC" number drops faster at the high end.

There are two main probable causes:

1. There is little/no/reduced Regen when the battery is near full, so the EV wastes energy braking.

2. This "pseudo-SOC" value might be derived from an estimate of the Battery Pack's "resting" voltage, which has a faster drop at 100% than at 50%.

We do not know how this "SOC" number is generated within the LEAF, but we do know that it goes up when we charge, can go up when we Regen enough, and usually goes down when we drive normally.

It might seem like charging to 90% or 95% (or about 11 Bars) might be an efficient choice.
 
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