Charging ebike in the boonies

[Jon R]

Those frying pans cycle the element on and off to maintain the set temperature. So it likely was trying to draw 1225 watts regardless of your low temp setting. I don’t think the frying pan test tells you the inverter is bad.

 

[Vic Harder]

Interesting. When I used my Induction cooktop, it does not cycle on and off. The induction stove at home does though. Wonder if all frying pans are on full tilt until they get up to temp?

I agree with Jon R, not a conclusive test. Got a space heater? I have one that has settings for 750W and 1400W that would work. Bit far to deliver it to your place though

 

[Jon R]

The frying pans that have a connector on the cord at the pan end with a temp dial, two outer electrical pins, and a central larger temperature probe work the way I described. You csn hear the power cycling on and off to maintain temperature.

 

[buckland]

Jon I think you are right as I hear mine do that and a red light on dial comes on and off in process....
I removed the inverter from truck and one of the two BB batteries and will open up the inverter ... I do notice the neg and pos terminals have a considerable 'wiggly-ness' .... maybe one/both are loose.... will report after opening it up.

 

[buckland]

I do have an old quartz heater ...that's up next

 

[buckland]

All fixed and nice and pretty. 2 BB 100 AH batteries and the 1000 W inverter ( opened it up and the negative terminal was loose) . Back in action... Drained my wife's small e-Bike battery and then charged it up in the camper set up ( it is a 1/3 the size of my ebike other battery that I will also be charging on the road). It took 2 1/2 hours. The battery was essentially empty. So The first shot is (from my shunt app) of well charged house battery bank at around 13.3 V (200 w). photo 2 is the battery spec and #3 is what it took to charge the ebike battery through the 1000 W Renogy Inverter from my 200 W (2) Battle Born battery bank...
Just a note ... my wife's bike is a Propella and it will do 15 very hilly miles up to 35 flat. ( she has a second battery we carry on the back rack just in case). My battery will be charge tested latter but its is a big one and the purpose of this is to be sure the extra BB battery will be reliable to recharge both ebike batteries after a days ride..... I got the feeling it will.

 

[PaulT]

36v by 7 Ah ==> about 12 by 21 Ah
21Ah of 200 Ah ==> about 10%
It looks like your session took about 7-8% of the battery.

I recall on another forum thread indicating greater than 100Ah for fully charged BB battery.
Seems reasonable for non calibrated instruments and ballpark specs

Looks like you are going to have a bunch of fun available.

Paul

 

[buckland]

Thanks Paul. My eBike battery is a monster ... can go 75 miles on it. 50 hilly terrain.... not that I have any plans for such things.. but as a dingy on the camper I am assured I can get fuel for the truck or get to a place to ask for assistance with it. I love a plan B.

 

[buckland]

Fiddle sticks. I though I was made in the shade. I discovered the negative bolt was loose. After that it seemed to charge the battery. HOWEVER .... I was charging a battery which was only half empty. I tried today with the battery nearly completely drained and the inverter would start out ok for 4 seconds than the overload alarm buzzed for 4 seconds. It started again ...same.... 3 more cycles and then the alarm came on and stayed on. As a reminder I have the 1000w Renogy Inverter. The e-Bike charger is a fast charger 58.8V 3 Amp (see photo) .

I do not currently have the inverter grounded to the camper bus bar..... could that be why it is kicking off?
Sigh.

 

[Vic Harder]

Rob, what gauge wire do you have feeding that inverter? How long are those wires? I'm thinking the Renogy is turning off because it is detecting too low of an input voltage under load.

And are you sure it is an overload alarm, or is it a low voltage alarm? see page 16 of the manual

500W-1000W-2000W-Pure-Sine-Wave-Battery-Inverter-manual.pdf (renogy.com)

 

[buckland]

Hello Doctor electric! Hope you are well Vic... Thanks for your help. I have very thick wire (1/2" cables ). They are 18" long. All connections tight. ( The inverter in not separately grounded to bus bar.... ?)

The charger starts ...on for 4 seconds then the alarm goes off and the red warning light comes on (the charger stops) this repeats four times and then the inverter quits. (alarm stays on until turned off). I

I believe it was Foy who stated the "Initial Power Surge" (also on pg 16) can go this. If this is so I suspect no Inverter would work? Wish there was a way to buffer that surge.

Weird though with the e-bike battery at half charge does not kick this warning alarm.
This problem is like a toothache...

Addendum: I just put my wife's 1/2 de-charged e-bike battery on the charger plugged into the inverter and all is working fine. It has to be the surge?

 

[Vic Harder]

LOL, Doctor Electric. I like it!

So, the way you described the behavior of the Renogy, it sounds like the low voltage alarm, not the overload. Check p 16 of the manual and the lights on the Renogy to confirm.

A different inverter will have different surge/overload specs and behaviors. I tested my Renogy 1000W when I had it, and it would deliver 1500W for 10 seconds before it shut down. You are only asking for 60V*3A = 180W from it. No way that should cause an issue.

I didn’t ground the frame of mine separately either, and it worked fine.

Inrush current can be a issue, but I can’t see it exceeding 100A…. No way. Can you monitor the camper battery voltage while you turn on the inverter?

Another test, bolster up the camper battery during the test. If you charge via the alternator (can’t remember if. you do or not) then start the truck, and/or plug in your shore power charger as well. That should boost the battery voltage enough not to sag when you power up the inverter. Monitor the camper battery voltage when you do this test too.

Let us know what you find out!

 

[buckland]

Your knowledge base is thoroughly appreciated. I understand what you are saying (that in itself is amazing !.. I struggle with this stuff). The one warning light/alarm for all of the issues makes it impossible to discern which it is. I have a Victron shunt which of course the inverter is attached to on the negative so should be able to see the draw. I started with my two house (B batteries at 14.V full charge with 200 Amps available. Nothing else on in camper. (Photo below is just before plugging in the ebike charger).
I will go out on the bike today to draw down the charge as I had in frustration plugged it in at the house so it is full.
Then I will try starting the truck for that test (I have a DC DC charger Victron). Thanks for taking the time on this.

 

[buckland]

Went out and did 15 miles of hills without pedaling (Just call me tubby!) to drain it down to about half.
I first tried as I did yesterday to see if having a mostly charged battery would somehow alter the results. No it did not.
I then started the truck. The solar panel was running as did the DC DC Bulk to Absorption.
(I have this sneaky feeling I have something not wired correctly but it all looks perfect as do all tightness on connections)
For what it is worth I took screen shots of the app while I tried to charge the e-bike battery. It cycled through on/offs four times, each 4 seconds then no more just alarm.

Added note: My wife's 42V 2 amp charger works perfectly well on the inverter.

 

[Vic Harder]

You have me stumped. I can’t really make out too many details from your photo, but given that your wife’s charger works fine….

How about another load, like a hair dryer? I’m really curious to know if it is in rush (not likely, as inrush won’t last 4 seconds). Or if it is total Amp draw.

 

[buckland]

I value your learned opinion. I too am stumped but I am thinking the 3 amp quick charger is the culprit not the inverter. I might buy the 2 amp one and hope that is the problem solved... If not I'll try to sell it.
Again thanks

 

[buckland]

I wanted to get back and say all is well. I sent for the standard 2 Amp charger (Instead of what I have been using which came with the battery... a quick charge 3 Amp Charger). And ...Bingo... plugged it into my 3/4 empty ebike battery and the inverter worked fine.
So something in that other charger allowed a surge as Foy had mentioned and there was no way around that on my level of understanding. Slower charge but I'll take it!

 

[Vic Harder]

bizarre. I'd be curious about what would happen if you had both bikes/chargers plugged in at once.

 

[buckland]

I will try that after the next ride. It was Rando who said the charger may have a real big capacitor which draws a lot of current (?) I call it a surge?... anyway I am thrilled I'll have both bikes able to be charged. I went from 98% to 78% charging the ebike battery. It is a BIG battery (70-80 mile range). So that is 40% of one of the 100 Ah BB for mine, and my wife's was 20%. So I feel comfortable that I won't be using any of the house juice... ample supply Just the low amp fridge and the heater and charge the iPhones etc. Having both the solar and DC DC charger I should be A-ok. I'll get back when I have tried the next step of both at same time.

 

[Lighthawk]

Hello fellow wiring enthusiasts!

I'm looking for some advice on charging my new e-bike in the boonies too. I found a 25% discount on a new Specialized Turbo Levo and made the plunge this week, just in time for winter camping season.

What I'm thinking is to use an inverter, powered by the truck while driving/idling to provide AC current to the charger.
Here's the specs: (Gurus please check my math, I'm a hacker and usually learn just enough to be dangerous)

TRUCK
RAM 2021 truck has dual alternators rated at 380 amps. 6.4L gas engine
Starter battery is 730 amp, 12v. There's a factory 115v / 150 watt outlet in the cab and truck bed.
I also have a set of auxiliary switches (factory option) with up to 40 amp (28A continuous) ratings, I've used them for fog lights, front camera and freshly installed ARB compressor under the hood. Pretty slick.

I had Zero Declination install a DC/DC Victron Orion 12/12 - 30 charger with #4 welding wire, with 80 amp circuit protector near the starter battery. Wiring terminates at the Victron shunt in the camper battery box. It's great to roll into camp with 100% SOC every time!

CAMPER
Camper battery is a 100 amp Renogy LiPo. Victron monitor reports 28-30 amps flowing to the battery while we're driving. We also have 130 watts of solar on the roof and a MPPT controller. We have a compressor fridge and usually after three days of camping are in the 80% SOC level.

I'm thinking I can mount a 1000 watt pure-sine inverter near the battery inside the camper, either directly off the battery (fused of course) or possibly from the Iota-30, which is on the opposite side of the camper.

But I could really use some advice on this. I see the benefit of having an accessible 120v outlet inside the camper, although we use all 12v/5v chargers for our electronics, AND running an "extension cord" to the front of the truck routed along the passenger side truck frame. I haven't sized what gauge wire that run should be. I wonder if a heavy gauge extension cord would work.

BIKE
700 wh / 42 v battery = 16.66 amp/hours
Charger 42v / 4 amp = 168 watts Charger is intended to plug into AC at home, so has a dual bladed plug on the input side. I probably wouldn't want to charge the bike under wet conditions. I hope I have the wattage correct here.

BIKE MOUNT
I installed a front receiver hitch and have a 1Up rack for two bikes that is rock solid. I want to run a 110v outlet to somewhere behind the front bumper so I can plug the charger in while we're traveling. Note: if temps are below 32F, I will remove the battery and bring it inside to stay warm.

I'm open to other ideas, and haven't bought the inverter yet. I thought about mounting the inverter under the hood, but by most reports that's a bad idea due to moisture, heat and dust.

Here's what I sketched up at lunch yesterday. I hope it's not too hard to read. "B" is the truck battery.
That's my bike on the front of the truck with the camper shown below.



Thanks!

Andy