EVT 4000e - a few questions

[phase_boy]

Good morning.

I am leaning towards buying a used EVT 4000e, 2010 model. I have no idea if the asking price is reasonable ($1000) for a lithium-powered 2010 model with ~8100 KMs on the odometer. The overall condition is said to be very good. I don't know the condition of the brake pads or tires.

I am hoping someone here will be able to clear up a few things about this scooter.

1. Were there multiple motor options on the 2010 models? The owner "thinks" that the motor is brushless, but isn't certain. In all of my research online, I see references to both brushed and brushless motors on the 2010 models.

1a. Any idea on the nominal output of this motor? Is it the classic 1500 Watt, or one of the slightly more powerful, newer ones?

2. Can the 2010 EVT 4000e carry two people (together we weigh less than 300 lbs) with any sort of composure? I am 6'1", so I know it'll be a bit cramped, but I'm more concerned with pick-up, medium inclines, and cornering.

3. What are the wheel and tire sizes for the 2010 model year, if different from previous models?

.
Thanks so much,

Sylvan

[phase_boy]

Alright then, no answers to those questions.

Quick specs: 2010 EVT 4000e, 40Ah lithium batteries, brushless motor, 130 amp controller, 8135 KMs on the odometer.

So, I went ahead and bought the thing. Rode it 25 KMs home in 2º C weather without incident (although I was freezing by the end of it).
After charging it up partially for a couple of hours, I couldn't wait to take my girlfriend for a ride. However, within two minutes, disaster struck:

I decided to test the scooter's hill-climbing ability with a quick jaunt up a short, steep hill. Ten meters up the hill, all of the lights went out and the scooter stopped accelerating. I was in Power mode with the throttle at almost full, going about 25 KM/h. I'd estimate the batteries were around 75% charged. Two of us riding with a combined weight of about 130 kg.

I pulled over and braked to stop us from rolling backwards down the hill. I waited a few seconds with the key in the Off position. Then I turned it to On. Nothing. Tried again a minute later, still nothing. Walked the scooter home (~10 minutes), then tried the key again. Still nothing.

Plugged in the charger (the charger has two lights, a yellow/green light and a red light). The red light comes on right away, then goes off a few seconds later. Then the yellow light for one second, before changing to green. The batteries definitely need a charge, but the charger doesn't seem to be providing power.

I am completely new to this scooter, so I don't know where to check for fuses. After about 45 minutes of checking it outside in the dark, I managed to locate two fuses. First, a blue 15 amp fuse behind the front access panel--fine. Then a yellow 7.5 amp fuse under the right-hand side panel, near the controller--also fine.

*** Does anyone know what is going on? Did I destroy something with that little hill-climbing test? I find it hard to believe that I did. Is there a heavier duty fuse somewhere that might have blown? A thermal breaker of some sort? The O.H. (overheat) light never came on.

Anyone here with experience or knowledge of the wiring? A wiring diagram, perhaps?


Thanks very much,

Sylvan

[amberwolf]

I don't know of a diagram here on ES; you might google around to see if there's one posted on the web someplace.

The charging problem sounds like there is something on the scooter preventing the charger from detecting the batteries. . Could be a breaker or fuse, or could be something in electronics, perhaps it's BMS needs to be reset or is faulty.

Do you measure battery voltage at the charger input?

[phase_boy]

An update:

I pulled the two battery boxes from the scooter. One box is slightly taller than the other.

The taller of the two boxes has the following information affixed to the side:
AM048040-B
Capacity: 40 Ah
Nominal Voltage: 49.4 V
Working Voltage: 54.6 V ~ 39.0 V
Weight: 11.25 kg
Amita Technologies Inc.
High Power Li-Polymer Battery

I checked its voltage via the Anderson plug: 28.5 V. Does this suggest that the battery has a good charge in it, and that it is connected in series with the other box to produce ~ 57V?

******

The shorter of the two boxes has this written on the side:
AM048040-A
Capacity: 40 Ah
Nominal Voltage: 49.4 V
Working Voltage: 54.6 V ~ 39.0 V
Weight: 9.75 kg
Amita Technologies Inc.
High Power Li-Polymer Battery

I checked the voltage via the Anderson plug: 0.00 V. Nothing. Does this suggest instead that this battery is dead? And that the above battery is at a dangerously low state of charge?

There are about 12 or 14 small screws holding each box together. Do I dare open them up for further analysis?


Thanks again!

Sylvan

[phase_boy]

Alright, I went ahead and opened up the battery box that was giving a reading of 0.00 V.

Inside there are 12 units, presumably 3.7 V each (?). They are wired in a mixed parallel and series system, so that each battery box produces one half of the nominal 49.4 V system. That is, there are six cell pairs making a nominal 24.7 V.

At the end positive terminal is a fuse of some sort. It is bolted on either side and wrapped in heat shrink tubing. Voltmeter readings from after the fuse show 0.00 V, and 24.4 V from the actual battery terminal.

So, I believe I have found my problem. Now my new problem is finding one of these special fuses for sale somewhere.


Sylvan

[amberwolf]

Post a pic with it's markings, and we might be able to help.

[commanda]

Sylvan,

I responded to your PM, and now I find your thread. Better late than never.
And those batteries don't get a mention on the makers website.

http://www.amitatech.com/product-Li-Polymer.htm

Glad to see you've tracked down the problem. Might suggest you need to go to the next size up fuse.

Amanda

[phase_boy]

@ Amanda, yeah, I found their website yesterday but couldn't find any relevant information.

The 40 Ah pack I have is split into two boxes. One box has 12 cells, the other has 14 cells. The 14 cell box has no fuse (and is giving a good reading), while the 12 cell box has an "ANE-80" 80 amp fuse (sometimes listed as an ANL type fuse, 32VDC / 250 VAC 80 A, often used in power-hungry car stereo applications).

I found a local surplus shop with the fuses at about six Canadian dollars, which is better than online sources. The scooter shop that sold this scooter to the previous owner offered to mail me a replacement (though they are in the same city as I am, Montreal) for "around $40." Thanks, ECOMOTO.

The question of going to a fuse with a higher current rating is tempting, but why didn't the controller's limiting circuitry (surely it has this..?) kick in? Is it possible that the only current-limiting device on the scooter is this difficult-to-get-to, single 80 A fuse? Is this what EVT means by protection?

I'm toying with the idea of replacing the fuse with a breaker switch, if this is going to be a common enough occurrence. I shouldn't have to do this, though; not on a scooter that cost more than CAD $5400 (the original owner, that is). Maybe a breaker isn't fast enough to protect the batteries/controller.

I don't know. Do you have any further thoughts on this?

I appreciate the replies very much.


Ta.

Sylvan

[commanda]

Sylvan,

I have the earlier model (2005) with the brushed motor, and the controller is current limited at 120 amps.
I also have a Doc Wattson, so I have a very good idea of what goes on.

If your controller is stickered as 130 amp, then that is what it will limit at.

An 80 amp fuse will let go long before the controller current limits.

With 2 up, ascending any hill, you will hit the controllers current limit.

You need a bigger fuse.

Amanda

[phase_boy]

Amanda,

First off, I found the spec sheet for the lithium batteries (Amita model AM048040) in my EVT:
http://www.thierry-lequeu.fr/data/AM048040.pdf

With that in mind, does the 80 A fuse not make sense? I guess what I'm asking is this: is it safe to ride the scooter, for any length of time, pulling more than 80 amps? I worry about the batteries and the motor in a case like that. I wish I had a Doc Wattson, or similar, so that I had an idea what kind of current the motor pulls under different, local riding scenarios.

As you've had your scooter for years, and you have a very good idea of what goes on, would you share some of your data?

Tomorrow I'll have the opportunity to buy a 60, 80, 100, 125, 150, 180 or 200 amp fuse to replace the blown one. According to the battery spec sheet, the peak discharge is 200 amps and the continuous discharge is 70 amps. Seems like the 80 amp fuse is ideal: likely the reason it was chosen by the manufacturer. On the other hand, I do want to be able to ride the scooter with a passenger up some minor hills.

I don't understand why the previous owner, in all of her 8112 kilometres, including riding double many times, in the same city in which I live, never had this problem (furthermore, my girlfriend and I together weigh less than the other couple). It confounds me.

I hope I am not sounding like a whiner; it's really not the case. I have been building and riding electric bikes and scooters for more than 10 years, and I've never been able to grapple with the competing ratings of batteries, controllers and motors. Throw volatile lithium into the mix, and I begin to lose my nerve!


Sylvan

[commanda]

I still stand by what I said. The controller will current limit at 130 amps. An 80 amp fuse will be blowing quite regularly.

And no, I don't understand how the previous owner got away with it. We are, of course, making an assumption here; that the 80 amp fuse has been there for the last 8112 Km's.

Knowing that the controller limits at 130 amps, I'd be fitting the 150 amp fuse. A fuse is meant to protect against fault conditions. Normal use will pop the 80 amp fuse. Only a fault condition will pop the 150 amp fuse. And it's still below the battery's max peak discharge of 200 amps.

And that continuous discharge rating of 70 amps. That's cruising along at full throttle on level ground. My scooter draws about 50 amps under these conditions.

Amanda

[phase_boy]

Hello Amanda.

I agree with what you're saying about the controller limits and fuse ratings. However, because the scooter has been in my hands for only a few days, I decided to be more conservative. Yesterday I went out and bought two fuses, a 100 amp and a 125 amp. Higher rated fuses are available, as I mentioned, so I can graduate up to those if this situation continues.

I installed the 100 amp fuse and took the scooter out for an extended spin. So far, so good. I tested full throttle under various conditions, went up some medium hills, and all was in order. Today we'll try riding two people on it again, and I'll do my best to avoid the really steep hills.

The Doc Wattson inline meter doesn't seem like it's really built to handle the possible currents in the EVT. Have you had problems with it at all? I saw another, similar meter with a slightly higher rating (than the Doc Wattson) that could also work. Or I could throw a heavier duty shunt in and wire it up to a little voltmeter on the dash; I'm very curious (as everyone here is, I guess) to know what kind of numbers this scooter is using.

Thanks so much for your guidance the last couple of days!


Sylvan

[commanda]

Sylvan,

The Doc Wattson needs an external shunt. There are instructions on their website, somewhere.
I think I have a photo of mine mounted in the dash cluster, also somewhere.
I'll see if I can find this info for you later.

Amanda

edit (2 minutes later)

read this.

viewtopic.php?f=14&t=4861&hilit=wattson

[ProDigit]

Just saying, from reading other webpages, the XB-700Li has the same issues, with the previous batteries.
It seems the 700Li has a low battery shut down. It requires you to unplug and replug the battery.
When in low voltage, you should accelerate slowly.

Second, batteries, especially Li batteries perform significantly less under cold conditions.
Charging them in cold conditions could burst the internals, as they expand greatly under heat, and in cold state shrink. The internals are heating up while the externals are cold could blast the battery, just as much as not using a battery, leaving it in full sunshine behind a glass window in a room, will also degrade the battery. THey are made to be used ~20C.

If you ask me from the first posts, charging them right after arriving home in the cold was a mistake.

second, the bike most likely triggered a low voltage shutdown, as the voltage significantly drops in cold weather.
It does give a higher voltage again when using the battery under normal temperatures.

[jorijnsmit]

Thank you for posting the spec sheet for the AM048040.

I am rebuilding these two batteries into a single one. Since I don't have the original charger anymore, I am asking for help to figure out the functioning of two wires.

First there is the yellow wire which goes to pin 5 of the charger; 'charger signal wire'. Do I understand correctly the BMS uses this to signal the charger to turn itself off?

Second there is a blue wire going out, labeled 'controller signal wire'. Any ideas on what this does exactly?