Need advice re: setting up a Luna Cycle 36V charger for use with Stromer ST-1

[Steve Plattner]

Hi, I recently bought a LunaCycle 36V charger to use in place of my Stromer ST-1 charger. Why? With Stromer batteries being so expensive, I want to maximize the life of each of the 4 I have (I do long trips) and only charge the batteries up to 90% to prolong their lives.

I disassembled the XLR 4-pin plug on my Stromer charger. As you can see from the attached pix, the power cable leading to the XLR plug on the Stromer charger has two leads--positive and negative. They are soldered and the connections are embedded in what looks like hot melt glue. And, inside the clear glue, you can see a small resistor (pale blue with 4-5 color rings identifying it).

Has anyone else tried to do this? Any thoughts on the resistor? Do you know of any resources who could do this for me--soldering, adding the resistor?

Thanks, Steve

 

[harryS]

Can't tell from your pictures what is going on. Are you saying that three of the four pins are used. Two pins have power/ground. The third pin has a one leg of a resistor on it, and the other leg would go to red? What are the four colors on the resistor?

The above isn't really needed if you're sure that only two wires go to that plug, and they are red and black. Verify with a meter that red is +36 and black is ground. Then chop off Stromer plug and connect plus/minus from the Luna charger.

You should use connectors to join the sections. Probably the same connector as on the Luna charger, which is an XT60? Then you can always fall back on the Stromer charger too.

If there's a third wire on that Stromer cable you didn't see, well, you cannot do any of this.

 

[tomjasz]

I dug around and found my Luna charger, it has a XT 60 male end. The easiest solution it to take an XT 60 pigtail female, cut the Stromer connector cord making sure you have a long enough original section to add the pigtail. Now you have an adapter for the stormer without messing with the resistor.
I took a couple of pictures to maybe make it clearer. It's easier to solder and join a pigtail than to solder a new XT60, for most people.

Essentially you'll be making an adapter like the XT60 to Barrel that is need for some batteries, yours will have the salvaged Stromer end instead of the barrel.

You can sort the resistor later and make a new end if you choose. It's easy to ID the resistor if you can see the colors.
If I can help in any other way, just ask!



.

Barrel adapter, yours will have the Stromer end

 

[tomjasz]

Steve, can you sort which pin has the negative and which the positive? The pins should be numbered on the front. Is the resistor across the NEG and POS? Is it 5 stripe? This should be an easy adapter and a great item to share on the internet. Who wouldn't want to have a longer lasting battery!

 

[tomjasz]

I posted your question on another forum, endless_sphere.com and got essentially the same idea i had. Making an adapter using the cable as i pictured.

The resistor is probably a "charger ID" and probably connects between the two non-power pins. You'd have to use an ohmmeter or multimeter set to ohms to find out what it's resistance is and what it's connection points are.

Your best option is to order the female XLR plug from Grin along with the Satiator, and use this existing plug on the Stromer charger plus it's cable to make an adapter from the Satiator's XLR to the Stromer's bike plug.

There appear to only be two wires on teh Stromer cable, and most likely Red is + and BLack is -, but you can use your voltmeter to determine actual polarity, and then after unplugging the Stromer cahrger from the wall, cut the cable off of it (leaving whatever amount of wire you wish on the charger, as long as you leave at least a few inches on the connector).

On the Satiator, the XLR uses two of the pins for power, and one for a sensor. You won't use the third pin, just the two power pins. You can plug the Satiator's XLR into the unwired female XLR, and use your voltmeter to measure which pin is + and which is -, by using the "force start" function on the Satiiator (holding the lower button until it engages charge mode).

Then solder the + wire from the stromer's connector to the + pin of the female XLR, and the - wire from stromer's connector to the - pin of the female XLR.

Close up the housings of the connectors and now you have the Satiator adapter cable to a Stromer.



The same basic instructions apply to make an adapter for any charger you want to use on it, that already has the right output voltage/current, or can be set to that.

 

[Ravi Kempaiah]

I dug around and found my Luna charger, it has a XT 60 male end. The easiest solution it to take an XT 60 pigtail female, cut the Stromer connector cord making sure you have a long enough original section to add the pigtail. Now you have an adapter for the stormer without messing with the resistor.
I took a couple of pictures to maybe make it clearer. It's easier to solder and join a pigtail than to solder a new XT60, for most people.

Essentially you'll be making an adapter like the XT60 to Barrel that is need for some batteries, yours will have the salvaged Stromer end instead of the barrel.

You can sort the resistor later and make a new end if you choose. It's easy to ID the resistor if you can see the colors.
If I can help in any other way, just ask!



.View attachment 16355View attachment 16354Barrel adapter, yours will have the Stromer end

Awesome work, @Thomas Jaszewski !

 

[tomjasz]

Old dog, new tricks...Just having fun learning. Thanks.

 

[Steve Plattner]

Old dog, new tricks...Just having fun learning. Thanks.

Wow, I appreciate it very much Thomas. Just saw your postings. I just posted an update 5 minutes ago. Took a different approach as I wanted to keep my Stromer charger and its XLR plug as a backup if needed in the future--decided against chopping it off and connecting the other end to the XT60 plug. They guy doing the work is someone I went to high school with--he repairs flat screen tv's and all sorts of stereo equipment and seemed very confident that he could make my Luna Cycle charger "Stromer compatible". I'll know for sure in 2-3 days. Will photograph and post the results soon.

 

[tomjasz]

Wow, I appreciate it very much Thomas. Just saw your postings. I just posted an update 5 minutes ago. Took a different approach as I wanted to keep my Stromer charger and its XLR plug as a backup if needed in the future--decided against chopping it off and connecting the other end to the XT60 plug. They guy doing the work is someone I went to high school with--he repairs flat screen tv's and all sorts of stereo equipment and seemed very confident that he could make my Luna Cycle charger "Stromer compatible". I'll know for sure in 2-3 days. Will photograph and post the results soon.

Please do have him take pictures and share the details? This is very valuable information and can help others. If I had the bike I'd want a Satiator adapter. You information will help develop and adapter and it will be open source. Not developed as a product for sale. The more we share and give back to the community its the stronger it grows. It may even inspire Stromer to do a better job with their chargers! The part number for the Resistor and the pinout for the plug you;d be invaluable!

BY THE WAY, I'm doing something similar with an adapter for a friction drive. I ordered the parts from China and am making 20 adapters. I am providing them to users for a donation to a Bike 4 Kids, 501(c)3 charity.

 

[Steve Plattner]

Thomas, will do it for sure. Give me about a week and I will post the details.

 

[Steve Plattner]

Wanted to update you on my quest to use a 36V Luna Cycle charger in place of the stock Stromer charger that came with my ST-1.

I took my Stromer and my Luna Cycle charger to a local guy who does electronic repairs. I asked him to open the housing on the Stromer plug, make note of the wiring and resistor, and basically copy it over to the Luna Cycle charger and the XLR 4-pin plug I provided him. He called me before starting to ask if I was aware that the Luna Cycle 36V charger really had an output of 42V--I told him I was aware and thought that was ok.

Before I go on, I opened up the new XLR plug to check out the wiring. First, if you look at image 272, you will see that the four pins are numbered--counterclockwise--pin 1 is at about 10 o'clock, 2 is about 7 o'clock, 3 is about 4 o'clock, and 4 is about 2 o'clock--I will refer to the pins going forward. Pin 1 connects to the brown wire (hot). Pin 2 connects to the blue. Pin 3 has the resistor attached (the resistor as you can see is a pale blue color and the color bands are: green/brown/yellow/red--it goes from Pin 1 to Pin 3)--see image 275 (left to right--Pin 4/3/2/1). Nothing is attached to Pin 4.

When I connected the Luna to my bike, the bike LCD read-out showed the battery at 42% of capacity according to the LCD readout on the bike (see image 262), and the LCD on the charger read 38.1 volts (see image 263).

Excited put the Luna Cycle charger to the test, I set the switch for an 80% charge, plugged charger to the bike, then plugged the charger into the wall socket.

Not sure what is going on--but it you look at the third photo (image 264) you'll see that the red indicator lamp is lit (indicating the power is on), but so is the green lamp--which according to the instructions should mean that the battery is fully charged--even though the bike LCD reports the battery is at 42% of capacity. Doesn't make sense. I left it plugged in for 30 minutes--none of the readings changed at all.

I asked the repair guy to test the output from the Luna Cycle charger to be sure it matched what the Stromer charger put out, and I assume he did. I will try to take some readings myself.

Sorry for the long explanation and many photos, but thought the more detail, the better. Would love to hear your thoughts.....

Steve

 

[harryS]

Two thoughts. 1) Luna charger not working. 2) Wrong size resistor. I suppose your guy checked it to be sure. The color bands of Green-Brown-Orange on the resistor says 51K ohms and Red means 2%.You still have the original Stromer charger, unmodified, and that works?

The green LED on my Luna charger, also 80%-90%-100% but no voltage display, turns red when charging. What happens if you plug it on first and then connect to the battery?

Sometimes nothing happens when I connect a charger to my batteries, in which case I power up the charger before connecting.

 

[tomjasz]

Ive just been told that Stromer chargers and batteries use ise Can bus communication. Preventing other chargers from working.

"A Controller Area Network (CAN bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other in applications without a host computer."

 

[harryS]

Hmmm. Well, if my router can send data down an AC power line, it ought to be easy to do it on DC 36 volts.

 

[tomjasz]

Hmmm. Well, if my router can send data down an AC power line, it ought to be easy to do it on DC 36 volts.

I'd have thought there would be a hack by now, but the fellas i think would hack the system would not be likely Stromer buyers. That said, some think the Satiator charger might work using the "force charge" function. That fellows remark was copied and pasted by me above, but i don't see how. I didn't get an answer from the maker. I'm sure they're not anxious to get a reputation for their product being used to hack a charge.

 

[tomjasz]

Well, i learned why i won't ever own a high end highly engineered eBike. They are not made to be repaired. Replace a wheel, replace an entire battery system, or replace the bike. Motors that have controllers in them, batteries with controller functions, and chargers with battery functions. It was fun reading for a few days... this thread on hacking and repairing ended the facination for me.

https://endless-sphere.com/forums/viewtopic.php?f=6&t=63809

 

[J.R.]

Well, i learned why i won't ever own a high end highly engineered eBike. They are not made to be repaired. Replace a wheel, replace an entire battery system, or replace the bike. Motors that have controllers in them, batteries with controller functions, and chargers with battery functions. It was fun reading for a few days... this thread on hacking and repairing ended the facination for me.

https://endless-sphere.com/forums/viewtopic.php?f=6&t=63809

There are downsides to everything, even with the most experienced DIY'er.

https://endless-sphere.com/forums/viewtopic.php?f=1&t=87975

I hate not being able to tinker, the device I'm on at the moment can't be cracked. You get what you need/want and figure a way to live with it. Hopefully with diligence, all works out.

 

[tomjasz]

Yeah, I know Dan. He made a fateful error in judgement. He knew better and broke his own rules. It's easy to do. I've changed a lot of procedures thanks to his sharing and honesty. But I don't see the correlation to eBike maintenance on the level of this discussion. Nearly everything I own can be sorted and repaired or replaced for ten of dollars rather than hundreds or thousands that some ride may require. I'm really not putting them down, or don't intend to. When I was fully employed and able I wouldn't have hesitated to buy a Stromer or such, and would have not fretted over a battery replacement or even a spare charger and new wheel/motor. But life changes, at least for me, and income did as well. Now like many of my eBike friends, we depend on our own skills to keep riding.

 

[J.R.]

Yeah, I know Dan. He made a fateful error in judgement. He knew better and broke his own rules. It's easy to do. I've changed a lot of procedures thanks to his sharing and honesty. But I don't see the correlation to eBike maintenance on the level of this discussion. Nearly everything I own can be sorted and repaired or replaced for ten of dollars rather than hundreds or thousands that some ride may require. I'm really not putting them down, or don't intend to. When I was fully employed and able I wouldn't have hesitated to buy a Stromer or such, and would have not fretted over a battery replacement or even a spare charger and new wheel/motor. But life changes, at least for me, and income did as well. Now like many of my eBike friends, we depend on our own skills to keep riding.

My reply wasn't to the greater conversation, but rather to your reply and comment about never wanting to own a high end, highly engineered ebike. Technically, what you're willing to own really has nothing to do with ebike maintenance either. No matter, we are many and varied. I do think there are far more ebike owners happy about their bikes, than there are posts on forums of frustrated and disappointed owners. Whether a $7k Stromer or a $1k DIY kit, there's room for them all

Sorry if I hijacked the thread.

 

[tomjasz]

My reply wasn't to the greater conversation, but rather to your reply and comment about never wanting to own a high end, highly engineered ebike. Technically, what you're willing to own really has nothing to do with ebike maintenance either. No matter, we are many and varied. I do think there are far more ebike owners happy about their bikes, than there are posts on forums of frustrated and disappointed owners. Whether a $7k Stromer or a $1k DIY kit, there's room for them all

Sorry if I hijacked the thread.

Hijack away...
I didn't write I never wanted or would never own a high end bike. Rather it's a financial choice for many, and is for me, in retirement. In my working days when my income was nearly 8 time what it is in retirement, I wouldn't have hesitated. BUT, I do think the $7K eBikes do themselves as much a disservice as the $1200 resellers. Neither are particularly good for the sustainability of the market. I'd be more excited if those highly engineered bikes brought new innovations and improvements to market, rather than just more proprietary and difficult to maintain machines destined for the scrap heap. I posted a link to some Stromers that were actually amazing machines, but were stripped to use just the frames. A shame by my thinking. But then I complain when my appliances last 5 years and they lasted 20 in my youth. What I' willing to own has EVERYTHING to do with maintenance. But you are right, we are many and varied. You and I are light years from agreeing, but I respect and honor all choices. Well most... (I have a stick in my craw for 40MPH Walmart bikes...)
As usual, I digress...