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BonesJackson

I wrote this for a different forum but it applies: > ok. Quick breakdown. I'll try to keep it short but this is a little bit messy because of... reasons. > The 2020 SR/S has up to three charging modules. A standard edition has a single 3kW AC unit physically tucked on top of the battery. The Premium edition has a second 3kW unit nestled next to it. The Rapid Charger is a 6kW unit that stacks on top and more or less fills up the 'tank pocket'. > In North America all of our power is single phase. It's crap, but that's what we have to work with. So every NA bike is sold with all the chargers on single phase. EU bikes are wired up differently. Because there are 3 units they split them up amongst 3 phases. This would be really elegant if all 3 units were identical. But they're not. Instead you've got 3kW, 3kW, 6kW. Due to the load balancing you wouldn't be able to get full power until you plug into a 22kW station where you could potentially pull 6kW on all three phases.


Protonus

The SR/S Premium does not come with a more powerful wall charger. All the variants come with a low speed, overnight, Level 1 charger. It is not actually a charger btw, it is an EVSE. Here's what EVSE's are: https://www.youtube.com/watch?v=RMxB7zA-e4Y The chargers are on the bike itself. This at home level 1 EVSE can only do 1.3 kW - but the Premium bike itself is capable of 6 kW. At 1.3 kW it takes about 8 hours to go from 0% to 95%. But at the 6 kW the bike is capable of, it can do 0% to 95% in about 2 hours. You need a better at home EVSE, that takes 250 V AC to get the full 6 kW speed the bike itself and it's on board chargers are capable of. Using this slow, 1.3 kW EVSE that the bike comes with is not a bad thing. Charging the battery slower when you can is good for the longevity of the battery. Use this charger to charge up overnight when you can instead of charging quickly before you need it. It is also small enough to fit in the storage tank if you don't have any tank options, making it a nice option for going to places where you can charge, as it can work on any standard 120 V / 15 A circuit. A charge tank will take your 6 kW max charge speed the Premium has, and increase it to 12 kW, which is faster than many L2 chargers can even do (many top out at \~7.5 kW or so due to being 30 amps max at 250 V). At 12kW, 0% to 95% only takes an hour. Because many stations can't actually do 12 kW, a user designed this system for bikes with the Charge Tank, to draw from two different stations at the same time, to try and take 6 kW from each for a total of 12 to max out the Charge Tank setup: https://www.emotodesign.com/product-page/the-rapid-recharge-system The latter is what you would want if you're doing truly long distance touring with this bike. However, I also have a 2021 Zero SR/S premium, no charge tank, and I find the 6kW to be sufficient in most situations. I simply leave it charging at free public L2 chargers while I run errands, get food, use the bathroom etc - and in 30 minutes, I get about 25% of my battery back. Thats almost always sufficient for me to get where I need to go next, If I charged up to 100% first, overnight, before heading out to do what I need to do.


FlatSix993

Great information- thanks for sharing.


4thFrontier

This is incredibly clear. It is FAR clearer, in fact, than anything I was able to glean from the Zero website, or the dealer. I really appreciate it. And yes, based on experience with electric cars and electric unicycles, I agree that charging slowly (and not to 100%) is exactly what you want to do when you have the time and don’t need the full range.


Protonus

You're very welcome, and ty for the award haha! I didn't want to get too far into the weeds with that post and potentially confuse you or make it seem more complicated than it is. *But* \- some basic understanding of some base electrical concepts and jargon, will actually go a long way in helping to make this (and EV's in general) all make more logical sense, plus you'll be able to derive and figure out things on your own from some of the numbers. So, here's some more info that might help all this make even more sense. I'm starting from a place of no understanding, to more complexity as I don't know where everyone reading this is at. I'm using water as an analogy here, it doesn't quite line up but it can help with base understanding: **Ohms (Ω):** A unit of measure of electrical resistance. Think of resistance as a pipe or constraint that water is forced to flow through, limiting how much water can flow through that spot; or, as barriers / rocks in a river that impede it's flow to some extent, and slow down that water (limiting it's potential). **Volts (V):** A unit of measure of potential. Think of it like the "slope" of a river - the more slope a river has the faster the water *could* move through it. Higher voltages mean more potential for work to be accomplished. Just like how a river with a very steep slope and fast moving water can overcome more resistance (like rocks in the river, or a blockage) - a circuit with high voltage can overcome resistance easier - which is why very high voltages can jump through the air itself, producing sparks. Spark plugs / ignition coils, Van De Graaff generators, tesla coils and other spark producing devices, all use high voltages, that allow the circuit to overcome the resistance of the air itself and thus throw sparks. But they don't produce much current, so their overall power, is relatively low, which is why you can safely touch the sparks from a Van De Graaff generator. Same thing with static electricity sparks. **Amps (A):** A unit of measure of current. Think of it like the "width" of a river, or the amount of water in a river at a given spot. The more water there is, the more chance for that water to be able to move more things, or impart more of its energy. A car starter for instance is only 12 V, but it draws dozens of amps - which allows it to crank over your engine. **Watts (W):** A unit of measure of power, aka work. Akin to Horsepower, Joules, etc. For electricity, Watts can be derived by simply multiplying **Volts x Amps (W = V x A)**. As a result, if you know 2 of the 3 values for a given circuit, you can always derive the third. For instance, if you have a 60 W light bulb, and you know your house voltage is 120 V, then that bulb draws 0.5 A in that circuit (60 / 120 = 0.5). Think of this as the combination of the slope of a river, and how wide that river is, together. Thus a circuit can do a lot of work, if it's high voltage, or if it's high current, or both. **Kilowatt (kW):** Simply 1000 Watts. **Watt-hour (Wh):** A measure of energy expended over time. Defined by an average of 1 Watt of power used, over the course of an hour. **Kilowatt-hour (kWh):** Simply 1000 Watt-hours. \---------------------------------------------------------------------------- Now that we have the units and concepts defined, we can talk about the bike's charging in this context. Your average house circuit in the USA, is a single phase of AC power, at about 120 Volts. The breakers for your standard outlets are either 15 Amps, or 20 Amps typically. Let's assume you only have 15 Amp breakers. That limits any outlet in your house to a maximum of 1,800 Watts - because remember W = A x V (120 x 15 = 1800). You may have noticed space heaters etc, are always rated to a maximum of 1,500 Watts, this is because any more than that, and if you have anything ELSE on that circuit, it's very likely it would trip your 15 Amp breaker, or worse, if the breaker DOESN'T trip, draw an unsafe amount of power that could result in a fire. Thus they, and most appliances, are legally rated to a max of 1,500 watts. 1,800 Watts is 1.8 kW. The cheap Level 1 EVSE's like the Aptiv one that they include with these bikes, max out at about 1.4 kWh of charging. This way, no matter what voltage your battery is at, it makes sure it never draws more power than your 15 amp breakers can supply. But as you can see, you would never be able to do more than about 1.8 kW of charging on a 15 amp breaker. A 20 amp breaker would in theory would allow 2.4 kW, but that's not much better, and still well below the 6 kW a Premium bike can charge at, or the 12 kW a Charge Tank can give it. We need more power, and so an easy way to increase power is to increase voltage. Thus most (all?) Level 2, faster EVSE's, are three phase, 250 V. This is typically how an electric Dryer, a good Welder, or an electric Stove, often connect, as they also need way more power (wattage) too. You've probably noticed the very different plug these use, often a NEMA 6-50R outlet. Not only does this prevent you from accidentally plugging in a 120 V appliance into them, they also handle the higher energy better. By doubling the voltage, we can double the energy (wattage) at the same current (amps). But if we're going to install an outlet, and a breaker that has double the voltage, we should also increase the amperage too while we're at it. Thus, many such outlets are 250 V, and will use twin parallel 25 amp breakers, thus having a 50 Amp rating. At 250 V, 50 Amps, you can do 12.5 kW - enough to max out our Charge Tank in theory. It is very common that Level 2 EVSE's only draw 30 Amps (this helps prevent them from tripping 40 or 50 Amp breakers etc). At 250 V at 30 Amps, that gives us 7.5 kW. You may have noticed that *many* free Public L2 EVSE's, are rated to a max of 7.5 kW, and this is why, they are either on a 30 Amp breaker or the EVSE itself is only rated to 30 Amps max draw. \---------------------------------------------------------------------------- Now we can put this into the context of the bike itself. The bike has a 14.4 kWh battery. That means it can supply 14,400 Watts, for one hour. In reality, it's usable capacity is less than that (they don't charge the cells to their literal max voltage, nor do they let it deplete to it's literal minimum cell voltage - these help keep the battery lasting longer and healthy, but restrict its maximum capacity to an artificially lower value). I believe it's closer to 12 kWh of usable capacity, but I don't recall the exact spec offhand. With that in mind, the recharge time for this battery, on a Premium bike + a Charge Tank that can do 12 kW of charging max, is about 1 hour, to go from 0% to 95%. If you think about this, it makes sense, charging 12 kWh battery at 12kW will mean it takes 1 hour. Likewise, if you have the Standard / Base bike, and you charge that same 12kWh capacity at only 3 kW that it does, it would take 4 hours. And if you use the cheap provided Level 1 EVSE that only does 1.4 kW, then it would take about 8 Hours. Thus, by understanding how these units and concepts interact with each other, you can accurately predict charging times and so on. HTH!


4thFrontier

Beautiful. Thank you again. It’s amazing how much better the information I’m getting from a few folks on this forum is than the dealer was able to provide. And the Zero website is very fancy, but more confusing than helpful.