GEM eL XD Truck - Upgrades - Lithium, R4F Motor, On-Board Solar Charging, 72v to 110v Inverter, Lights

For those of you interested in the progress of my various electrical upgrades…

Switches

  • The solar switch interrupts the connection from the solar panel to the MPPT boost charge controler. The solar charger is powered from the panel, not the battery. (12ga)
  • The inverter switch is just a relay extension wire I spliced in from the inverter which is buried in the box under the seat. (18ga)
  • Heater is, again, just a relay switch and existing wiring was right there.
  • The rest control the LED zones.


I also swapped the 12v cigarette lighter plug because I am a non-smoker. :wink: It has quick charge USB ports and a handy volt meter so I can monitor the 12v supply.
https://www.amazon.com/gp/product/B07F84VVB4/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

120v Outlets
In cab with USB:


https://www.amazon.com/gp/product/B07DD5YKFZ/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1

Inside MaxBox, front of truck bed:

External recessed In-use box on rear of truck: I put it on the back just in case I might forget something was plugged in and drive off. In that event the plug would just be plucked out.


https://www.amazon.com/gp/product/B004K1G0PE/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

This required relocation of the license plate holder… extra little upgrade. :sunglasses:

Trailer Hitch
I cleaned and re-painted the trailer hitch with Rust-Oleum enamel and spliced in flat 4 trailer wiring. I found a nice forged aluminum hitch piece and a nylon capped ball made by Anderson with my favorite stainless hitch pin I always recommend. I really don’t like rust.



https://www.amazon.com/gp/product/B000GGI6MM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B001GC67AS/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B000COX0MY/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

Solar Panel Installed on the roof rack


I added a piece of aluminum angle front & back because the panel was just a little short of making the full span. Lots of extra work for less than two inches but it has the added benefit of adding rigidity. I kept all hardware aluminum or stainless, of course.

Solar junction… you can see other wiring for lights, etc behind it.

The rest of the Addressable LED pixel lighting
Finished the LED lighting except I have not yet installed the frosted covers for the LED channel.

There is one controller in the back of the box which places it as close as possible to where most of the pixels originate. The controller has a direct power feed and the whole 5v DC converter supply can be switched off and on with a switch I added under the e-brake (afterthought). It is a 40a supply at 5v so you might say, @Gemrix isn’t that too much for that little switch? I thought that too but then I remembered that I am actually switching the input side which is less than 3A peak @ 70-80 volts factoring in the efficiency of the converter.


These strips can be a bit sensitive to voltage drop because they run at only 5v. Every single pixel has it’s own IC chip. This is why I over-sized the 5v PSU and wiring.

PS: Wago lever nuts as seen in that box are way more fun to work with vs old-school wire nuts. You can mix wire guage and type securely. I added a weep hole in the box just in case the cable glands through the roof would ever leak. I did shrink wrap the little bundle of wires to the LED strips.

CAB, 48 pixels (14ga power & data wire return because of the longer run)

BOX, 93 pixels (14ga power & direct splice for data)

TOP, 205 left + 205 right = 410 (12ga power, and 2x direct splice data)


20190608_140516|690x388
!

551 pixels total :astonished:

I still plan to post a video of the pixels in action when I get the chance.

Camera Mirror
You may have noticed the rear camera in the pictures of the LED strips. I installed a mirror that actually has a front & rear camera, recording of both, GPS for speedometer readout, clock. The GPS sensor is under the front dash. I used the same cable raceway as I did for the pixels in the back of the cab. Again it was a pain to fish the wires down through the tubular frame.


Totally off topic… check out that yard in the mirror. We have been having plenty of rain and it is sooo green. I had a small landscaping company from age 15-22. I also still have my hobby business that I started in Y2K DJing (weddings, proms, etc). I’m AKA “Rixound” and this may somewhat explain my need to integrate smart lighting into my GEM. The lighting obsession is actually even deeper though. I was once AKA “Kress Kringle” with one of those big animated light displays from 2009-2015.


Now I am a financial advisor by profession. I realize most financial advisors are not out self-installing solar or geothermal or animated light displays or setting up speakers and uplights in the convention center for fun on the weekend, or tricking out the GEM car. My wife might tell you that I am a little bit nuts, but in a good way.

Anyway back to the GEM
$109 with coupon
https://www.amazon.com/gp/product/B07PD2KJQH/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

By design this is supposed to strap on to the existing mirror. It’s a good thing I already thought that was kind of lame :stuck_out_tongue_closed_eyes: because the original mirror placed the front facing camera up in the blue tinted area. So I got a simple magnetic windshield mount, ripped it apart and added 3M adhesive instead of the magnet.

https://www.amazon.com/gp/product/B07BS4S89H/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

Control Panel
A La Tesla… If you have been following along you know that I had a BMS remote and part of a solar charge controller dangling around the front dash. I decided to make a box to make them neat and accessible.

I started with a hobby box
https://www.mouser.com/ProductDetail/hammond/1599kbk/?qs=4dK74SdgGtw2sskdoLi2Ew%3D%3D&countrycode=US&currencycode=USD

Then I measured and marked it up trying to center the screens in a vertical line. I got out the rotary tool and went to town.


note the spare box upper right just in case I screwed up, and I did.

Just 4 “short” hours later and voila!


Speaking of screens; the round thing at the top is a wireless charging phone mount that works with this sticky nano stuff, you know, science. The LED’s are Bluetooth controlled via an app as well as the many other things a smartphone has to offer the well-focused driver. :police_car:

Now to make it look pretty and finished… My first thought was to mask it off and spray with Plasti-Dip rubber. Instead, I ended up putting the box face down on a scanner at this phase. Then I edited and augmented the resulting image in MS paint & Photoshop. Finally I printed it out and laminated it. This ended up taking some trial and error. Credit to Wifey for letting me borrow her special craft cutter and Martha Stewarts own razor circle cutter thingy.
https://www.amazon.com/Martha-Stewart-Crafts-Simple-Circle/dp/B002BTUHBU

If you look really close you can see that I still need to refine the screen cutouts a few mm one way or the other. If you are looking at a distance… it still looks pretty homemade. I may look into matte finished lamination pouches or getting this printed on vinyl, maybe. It’s more than adequate for proof of concept, nonetheless.



!

Solar Charging
This actually works!


In this mostly sunny example, it is putting out over 1 amp. It is comforting to see it accurately measuring the pack voltage (note how it almost matches the BMS).
I an still messing with the settings but I currently have it set to cut off at 82v with the panel voltage plugged into to improve the targeting of the MPPT (Maximum Power Point Tracking). I have to go re-watch some videos because there is a way to configure the battery pack capacity to get a more accurate charge progress indicator.

The manual leaves a bit to be desired and I found plenty of videos on Youtube. Just search MPT-7210a and settle in for a British documentary on the subject.


The loud fan as seen in the videos is not a problem. I cut out the vent circle as suggested by some dude on YT. However on the unit I received, the fan has not run at all yet. Either they updated the design to be thermostatically controlled or I forgot to hook it back up or it is a bad fan. It is not heating up at all though and will not be pushing it to near capacity, but I will investigate.

Cleaned Up
My GEM is not cosmetically perfect. I got it in basically non-working condition. I took off some crappy stickers and the rest of the word El*ctric missing letters. The 7.0 badge no longer applies. I may order replacement door decals because one was damaged and I removed the other to match. I re-seated the rear window and added a couple of retainer screws (seems like a flawed design for the rear window the way it bowed up in the middle). I need to reinstall the front heavy duty bumper which I cleaned and repainted in aluminum silver. I have new tires & some unique throwback “full moon” stainless hubcaps to install.
Maybe a few well placed reflective strips or a trip to the dent doctor would help but she cleans up okay. She’s definitely one-of-a-kind and she’s my little GEM.

That reminds me… I’ve had insurance for a month and sent in my paperwork the same day and I’m still waiting on that “RIX-GEM” plate from PENDOT. No temp tags for NEV’s in PA and did not even have a law pertaining to NEV’s until 2014

1 Like

I love your GEM. Man have you been busy. It just makes me want to work on mine some more. Your motor will be fine.I’ll get a new magnet or just swap mine over. Keep up the good work. Loving it.

Very impressive, not just the great mods and your vehicle but to know there is a financial advisor who actually knows how to make something.

Congratulations.

The motor arrived from D&D! It is model ES-132-68 and was manufactured 10 days ago.

Here are the three motors lined up for comparison.

Ride-4-Fun motor is 9 1/2" long
Stock GE motor is 11 9/16" long
New D&D motor is 11 1/2" long

Measurement of the body of the motor body excluding speed sensor & wire.

Installation ended up fine with only one minor adjustment needed. The mounting bolts had the motor lined up either rolled forward slightly or rolled back slightly with the lugs not facing straight up. One of the “F” wires was about 1/4" too short to reach. Fortunately, I was able to swap the two “F” wires and it worked out fine. One was about 1/2" longer. I took off the labels to avoid confusion and they are clearly labeled on the gray controller box. I did have to apply new silicone around the “F” wire connections to the controller as it had before.

The black plastic air scoop fits fine and with the motor rolled back, the wires are somewhat better protected.

It is pouring rain tonight so I will wait to test drive it tomorrow. I will test first as is, then add the Magic Magnet as before.

This thread mentions the same motor but with no indication of actually installing one. Other than “the guy in Florida” I may be kind of the Guinea pig here.

Based on comments from @Old_Houseboater it looks like it may be a good thing I opted for a D&D performance motor because of the higher potential RPMs at around 30 MPH. Remember, my eL XD has the 14.76:1 gears and bigger stock tires.

One question: Are higher RPMs only an issue under load on flats or uphill vs. coasting downhill @ 35 mph for example?

I also found some discussion about the motor here:
http://www.buggiesgonewild.com/electric-ezgo/95868-sepex-series-rookie-question.html
They talk about 8hp and 16.5 (at 48v) peak and typically higher torque in a longer motor. How does voltage affect HP? The motor label says it can operate at 36, 48, 72 volts but does not show HP.

Elsewhere on this site they discuss heat of this motor @ 48v.
http://www.buggiesgonewild.com/electric-ezgo/102983-high-torque-motor-getting-hot-will-bigger-controller-2.html
A couple of positive takeaways from this as it applies to my setup…

Just a technical expansion on the highlighted comments.
The Ohm’s Law formula for power that is usually seen is I x E = W. (Amps times Volts equals Watts)
However the Ohm’s Law formula that tells the tale best is: I² x R = W. (Amps Squared times Ohms equals Watts ---- or Amps times Amps times Ohm equals Watts)

*Basically, by increasing the pack voltage from 36V to 48V (a 33.3% increase) you reduce the amps by 33.3%, but reduce the heat by 66.7% (times the efficiency of the motor at the same RPM and under the same mechanical load) *

In other words the relationship between Amps and Volts is linear while the relationship between Amps and heat is exponential.

  • Good because my ~80v should run much cooler. I’ll get a heat gun just because it would be good data to have.

*What gear ratio is your differential? *
If you have stock gears (12.44:1) going to 14.96:1 will almost offset the heat problems caused by the 23" tires.

  • I have 14.76 with similar tire size, so good also.

Not sure, but I don’t think the bms-24t uses the temp. sensor input for other than display and alarm.
The inputs could then be used for other functions. Such as controller and motor temperature.

I like that idea! Thanks.

First impression of the motor: oh shoot, why am I going forward? Apparently, the rotation of this motor is opposite of stock. Fortunately, I remembered the label on the toasted R4F motor that said to swap the “F” wires for CW vs CCW rotation. So it turns out that motor was good for something after all. Ironic because I had swapped the wires during install for length. So it is F1 to F2 and F2 to F1.

First impressions take two (only the motor swap at this point, no MM): It did not seem much different from the stock GE motor. It is slightly quieter and very smooth acceleration and deceleration. It has, perhaps, more apparent pick up and acceleration 0-15 MPH then a more gentle roll-off of that acceleration curve as approaching 25 MPH. Unfortunately it actually seemed weaker near the top end vs. stock. It does not get overly hot. After a 6 mile loop at full speed, it measured 130 degrees on the body of the motor.

Then I installed the Magic Magnet. Top speed on flats was about 29 MPH. The stock motor did closer to 32 MPH on the same stretch. Of course the speed sensor magnet did split during this test with the old motor. Now I am wondering if that was just a coincidence or if it was really spinning too fast because of my 14.76:1 gears. The RPM rating of the stock motor is the one thing that still has me looking at the D&D motors which will reportedly tolerate higher RPMs.

I’m not sure what I am missing here but it is not an upgrade as is. Does this motor need more available current (higher amperage)? @Inwo advised in another thread that higher amperage can lead to more complications. On paper it should be easily beating the stock 7.0 motor. Looking for theories or opinions, please. I will have to wait until Monday to talk to Vic to see what solutions he can offer.

Looking at d&d site they don’t share much data on their motors.
Did they promise more than 25mph?
How tall are your tires?
Can you find safe rpm limit? 5,000 rpm maintained is what I’ve heard for stock motors. I doubt d&d wants you over 6,000.
You can force it higher with more voltage or less field current, but gear change may make more sense.

Thunderstruck has a performance curve for 72v d&d motor.
Only goes up to <5,000 rpm. Nothing I can find hints at higher speed.

image

Tnx to @Old_Houseboater

  • Yes the data on the motors is hard to come by. I bought the motor on the recommendation of Vic at D&D during about a 10 minute phone call. There is a bit more information in this Amazon listing:
    https://www.amazon.com/gp/product/B06XNSKWS6/ref=ox_sc_act_title_1?smid=A1RMJN1BDI6QEK&psc=1
    Aparently the Green option of the Blue motor is High torque, lower speed, to prioritize range. The Red option of the Blue motor is high torque and speed at the expense of range. That’s not confusing at all. :stuck_out_tongue_winking_eye: Until now I was not even aware of this variation and Vic may have simply misunderstood my goals. You and I know that my battery pack is plenty oversized. My #1 priority is pulling power: This is supposed to be the “hayride” & yard work machine. Ironically the torque motor I currently have does not climb hills as well as the stock motor. The only thing an “upgraded performance motor” needs to do is exceed the stock capabilities.

  • They will not even discuss higher than 25 MPH or really any electrical variations, I think because of warranty.

  • My tires are stock (for eL XD) 23.2" and I have the 14.76:1 gears. The chart you are referencing is actually the reason I became concerned about RPMs with my gearbox (after my magnet blew in the stock motor at 32 MPH - possibly coincidence)

  • The higher RPM rating of D&D is mentioned in discussion on the forum, for example:

Ride-4-Fun touts higher RPMs an higher temperature tolerances too:

  • “6,000 RPM Sustained Operation Rated, with up 7,000 RPM operation (25% higher than other performance motors, and 50% higher than stock motors).”
  • “Patented design delivers more power, generates more torque, increases brush life, and reduces heat which results in higher speeds, quicker acceleration, and increased reliability/motor life.”

I would be content anywhere over 30 MPH on flats.

Finally, I did not find the ES-132-68 Motor that I have referenced on this site initially but now I found that @grantwest actually has had some experience with it discussing a “New Torque Motor” Check the picture, it has the same model #.

I would be EXTREMELY interested in any further insight you have, Grant.

Really, I hope this discussion will help others who may be trying to find the best combination to unlock the potential of their GEMs too.
(otherwise I would not be so damn wordy and nerdy :nerd_face:)

Looks like I should really not exceed 32.5 MPH for any length of time.

Thanks @Old_Houseboater from me too!

Thanks for sharing, I’m going through a similar exercise where I’m converting my 2013 E6s to lithium and need a new motor. I have the original 12.44:1 gearbox in the car now but I also have a 10.35:1 gearbox to use. I plan to buy new wheels and tires so I have all these variables to consider. Its nice to have all this flexibility but also a bit hard to figure out the best combination for my goals. @LithiumGods was nice enough to loan me a 7 HP Advanced motor so I can get some baselines to reference and build on.

In my search for a new motor I also contacted D&D and have exchanged a handful of emails with Eric over the past month. He has been recommending the same ES-132-68 torque motor you have now.
The other “speed” motor is the ES-132-69. @grantwest has the same ES-132-68 motor as you in a cart he built for someone and @Jb0389 has the other one (ES-132-69). Those are the only two folks I could find with firsthand experience with these motors.

I’m not yet sold that the torque motor is the best fit for me but D&D seems pretty confident in that it is. While trying to understand the differences between these two motors Eric said the ES-132-69 motor has higher rpm and current draw and lower torque output. It’s most often used in 48 volt LSV type vehicles. He said since I will be operating at 96 volts he wouldn’t suggest the ES-132-69 motor. The ES-132-68 would be the better motor for overall performance and run time for my application. He suggested adjusting the field current to find the right torque and range balance and also said the peak rpm for both motors is 6,500.

Thanks @RS_E6 for the additional information. My current inclination is that with my 14.76:1 gears the “speed” of the motor should be the priority because the gears should take care of the torque to some degree. I am thinking of it like pedaling a bicycle very fast in a low gear to climb a hill. I originally talked with Vic and he was in kind of a hurry. I asked if he needed to know gear ratio and he said no.

Again, I am also fine with sacrificing some range because I have a 160ah pack with a highest SOC under stock tolerances @ 82v.

It may be wise to adjust the dip switches on the Magic Magnet to enforce the 32 MPH if possible. How do the settings work on the MM @Inwo?

Also, does high RPMs have the same potential for damage under essentially no load going down a hill?

Thanks guys.

One more inquiry, how would one adjust field current?

Turn all switches to off for minimum speed increase of a couple mph.
Switches are additive in binary fashion. 1 adds a little more.
then 2, then 1+2, etc.

@Jb0389 said that D&D told him he had to get the ES-132-69 speed motor due to his 14.7:1 gearbox. They told him the ES-132-68 torque motor would not even go 25mph with his low gears. My guess is they were focused on your need to tow and just immediately went to the torque motor.

My understanding is you can adjust the field current through programming the controller. I got the data cable and software from @Inwo and have peeked at it but I’m still getting my batteries sorted so I haven’t started modifying the controller yet. I’d be really interested to hear how the torque motor behaves under different field current settings.

Careful with field current and watch for motor heating. Field current is needed to keep motor happy.

At one time I researched a hardware fix that would switch motor into speed mode by reducing field current. Wasn’t much interest at the time.

Yes, Rodney calls it grenading. I have not seen it myself.