Aussie 200 Watt Limit Thread

whatever said:
old rule : 200watt maximum ( equates to approx 130watt continuous)
new rule : 250watt continuous ( equates to approx 750watt max)
both rules still apply just to confuse things a bit more
old rule used maximum power ( 200watt), new rule uses continuous power ( 250watt)
The regulators did eventually work out the difference between continous and max ( peak power)
How does that work exactly? I mean technically, how does 250W continuous equal 750W peak?

Cheers
 
I'm not sure if it's hard and fast but I think it was the result of dyno testing to arrive at the 250w figure. This was one of the first questions I asked someone in the industry who was certifying euro compliant 250w PAS ebikes. And also what sort of battery current they were drawing to achieve 250w on the dyno (from memory they were pulling about 800w peak - from the battery)

What I imagine it means is the motor is tested such that it's putting out no more than 250w when cruising at 25km/hr. To me this is what continuous means - travelling for extended periods at top speed (well, when the speed is limit to 25km/hr it's pretty much top speed from the second you roll out your driveway until you hop off at your destination!) This allows for higher power when launching off the line or lugging it up a hill. The continuous thing also has to do with motor temperature so it wouldn't be reasonable to stick say a 5kw controller on a little geared motor and hope to have it survive if you dragged it up a steep hill. I don't see any reason you couldn't put a 20A controller on these speed limited PAS bikes though instead of the typical ~12A ones. As with any of these pedal assist bikes though, no matter how torquey they are being limited to 25km/hr is still the weak link in making these a viable form of alternative transport for serious bike riders.
 
It would appear to me that who ever is drafting these regulations, has very little understanding of electrical drive systems, cycling, or social planning for that matter !
As usual, Aussie authorities wasting time on trivial details whilst the real issues ( transport congestion and costs) get ignored !...( Ah , no, sorry, they are f'ing with that also ...Trams on George St !)
 
to determine maximum output power of a motor from a given continuous power rating depends on which definition is used,
there are various organisations etc that give definitons that relate continuous and maximum output power, depends on which one is used on what values you get.
I used a definiton I got from a german website just happened to give 250watt continous brushless motor data ( it was many years ago sorry I cant give link to the website, I have searched for it without luck), 750watt will be pretty close to max output power for a 250watt continous brushless motor, it shouldn't matter which definition used they should all give similar figures.
The new laws in oz, they dont give a max power output rating, only continuous, who knows what reasons they have for not giving maximum power rating. If would be quite helpful if they would publish it somewhere.
If someone were to be taken to court for an overpowered ebike, they would then need to work out their value for max power rating, or at least it would become public knowledge.
 
not sure if this govt paper has been linked before
http://roadsafety.transport.nsw.gov.au/downloads/motorised-bicycle-tests.pdf
Although its for petrol bikes, it does give some info on one electric bike the govt tested.
According to this paper on page 9 section 3.2.2
Electric motors are designed to produce a continuous power output, which
is the amount of power they generate while they operate over a prolonged period.
They are also capable of producing considerably more power for a very short period, known as “peak power”.
Peak power cannot be maintained for more than a few seconds. Peak power does not affect the
continuous power rating, and is allowed under EN 15194. This is a useful feature as it
allows a rider have extra power at certain times, such as when pulling away from traffic
lights or starting to climb a hill

That is not really a hard and fast defintion ( I've put in bold the grey area), I would think the govt hasn't actually determined an exact peak output power thatis allowable, but you can be sure if you went to court they would find one.
Although the author is suggesting there is no peak power limit, there will be one if a court case arises, they will find one.
The article is not completely accurate:
for example
Pedalecs are a newer type of power assisted pedal cycle. Although they are have more
power than older types of power assisted pedal cycles 250 watts compared to 200 watts

this is offset by enhanced safety features: the rider must pedal for the motor to activate
(with the exception that they may run up to 6km/h without pedalling to facilitate low
speed startup), and the motor must cut out once a speed of 25km/h is reached, or sooner if the
rider stops pedalling.
The author suggests pedelecs are a new type of ebike with 250watt cont power limit, and that old ebikes were
200watt, this is completely incorrect. There never were any 200watt ebikes in australia ( with one exception).
He/she makes the mistake of not saying that the new rule is continuous and the old rule peak power.
To be correct he/she should have written 250watt for new ebikes and 130watt for old ebikes ( 130watt continous is approx 200watt peak), that way both rules are written in the same units i.e. continous power.
99% of ebikes in australia have always been over 200watts peak ( 130watt continous), it was just that no one was testing or worried about ebikes, until they police got involved, then the govt had to look into it.
Its still not black and white, at the moment there is a grey area over peak power allowable. You could argue there is no peak power limit, but there will be if govt needs to argue in court.
 
the problem is the power output of the motor is supposed to decline the faster you go ( under current regs which just copy the eu regs, when you reach 25km/hr there is supposed to be no assist by the motor!!!. The article I linked above is not a bad read, to get an idea of what the govt researches view of the regulations are.
Its a load of bollocks in my view. If I were making up the rules, I would just say 48v 20amp max power of the controller ( approx 800watts), dont worry about pedelec rules etc, just make it simple to understand and simple to enforce ( if they feel a need to enforce it).
800watts is enough power for most people.
If anyone wants to go over that voltage/power limit then have a special licence,
for small fee, some inspection of the ebike to make sure its safe for higher speed/power. Then anyone wanting to go fast or long distance on ebike could be legal.
The big problem is if anyone is taken to court , then the exact current regulations become very important.
Also very important for retailers to cover themselves against lawsuits.
Lets have an all australian solution to suit us, rather than simply copying eu regs.
 
The old rule ( 200w ) was for petrol bikes - Electrics came much later and you're right that most can't make it within the 200w limit ( I have one, but it took me a while to figure out how to set a maximum power exactly. I start at 125w and boost beyond that with power control ).

The problem is that the government started buying pedelecs and they were all illegal, so the laws had to change. Meanwhile there was a group of people who didn't like petrol, so they did a hatchet job on petrol bikes, and now the laws are so messed up that technically, no assisted bicycle is perfectly legal in australia under either standard - and you're also correct that it's going to have to be tested by the courts. I pity the first victim who gets to be the guinea pig for that event.

Anyway, in some states like WA, QLD, they passed additional laws limiting the maximum power of pedelecs to 250w ( Not the maximum continuous ) - this makes no reference to the standard, so technically pedelecs are illegal in both states through poor lawmaking. EN15194 does define maximum power as peak power, so that's not exactly helpful to those trying to comply.

200w bikes still are legal, but are difficult to make compliant... I've set mine to about 150/170w at the moment, but once I finish my dyno, I'll set it to 195w. It uses voltage boosters to offset the back-emf from the motor and can boost operation to about 40 kph given the right wind or gradient conditions - all within the rules.

As for Pedelecs? They seem OK in NSW since they've issued guidance that it's maximum continuous there, not peak power, so NSW is somewhat OK, but the bicycles are possibly illegal under other guidance about how long the power assist can last - This was due to a court case in which they tried to ban electric scooters. This is a problem because EN15194 doesn't set any time limits around this, so some bikes won't comply.

Under the EN standard, 750w peak sounds pretty accurate and is about what I'd expect, but if the power isn't zero at 25kph, then the bicycle is a motorcycle. Most start to lose power around 19 kph and continue until 25 kph as the drop-off in current must be linear from peak to zero. However, it's this characteristic that makes these bikes dangerous as they can take off suddenly while pedaling slowly and can continue to provide full power (800w as was mentioned) for up to 5m - which can lead to collisions with pedestrians.

Anyway, I'm more pro-petrol :) So I made up a petrol based system that conforms to EN15194 and recently got it approved for operation under WA law for 250w, so technically it is possible to meet the standards - it's just that many pedelecs will not.

Regards
David
 
I passed a guy last night on a carbon Cervelo with all the racing fruit and tight pants. I was going pretty hard around 35 kph pedal and electric motor 250w. In the end the guy was so fit I let him pass after about 10 km and he pulled away. This was on bike paths. According to the ebike rules we were both exceeding the limit quite a bit.

There is talk about a speed limit on the bike paths, which are shared with pedestrians. A speed limit rather than a power limit would seem to me a more practical approach covering both ebikes and high performance cyclists. After all there is no power limit for cars only speed limits.

On the road 40kph is slow and really not an issue. Cyclists in a group can easily sustain 40kph so why not ebikes?
Most half fit guys on a light bike can exceed the 25kph limit set for ebikes quite easily.

I feel we should be urging the law makers to make the rider responsible for his actions, ebike, petrol assist or high performance cyclist, rather than trying to restrict machines.
 
Just a notice to all: the legislation was introduced to ban petrol bikes completely in the ACT. It was only submitted today, not sure when it will get through but I'm sure it will.

Regarding the paths, yes, it should be a blanket speed limit. An electric bike is only dangerous because of the speed. The old "frame and brakes might fail as they are not designed to handle the speed" argument. They don't take into account that the bikes are identical or stronger than they see on the red bull rampage and such. Pretty sure a stealth/raptor would hold up just fine compared to a moto.
 
bandaro said:
Just a notice to all: the legislation was introduced to ban petrol bikes completely in the ACT. It was only submitted today, not sure when it will get through but I'm sure it will.

Regarding the paths, yes, it should be a blanket speed limit. An electric bike is only dangerous because of the speed. The old "frame and brakes might fail as they are not designed to handle the speed" argument. They don't take into account that the bikes are identical or stronger than they see on the red bull rampage and such. Pretty sure a stealth/raptor would hold up just fine compared to a moto.

Do you have any further details/links to this?

Thanks
David
 
Not really, basically just says the thing was brought up, and says it will align with other states so probably go ahead.

http://www.abc.net.au/news/2015-05-14/drinking-alcohol-while-driving-to-become-illegal-in-canberra/6468142
 
bandaro said:
Not really, basically just says the thing was brought up, and says it will align with other states so probably go ahead.

http://www.abc.net.au/news/2015-05-14/drinking-alcohol-while-driving-to-become-illegal-in-canberra/6468142

Thanks for posting that - it's of significant concern to e-bike riders too - remember that the basis he is trying to ban petrol bikes on is that 200w petrol bicycles can travel at "dangerous speeds" that bicycles aren't designed to handle...

Not a good thing for any of us, since 200w electrics actually go quite a bit faster than 200w petrol bikes.

David.
 
Yep it's f@$#d! I'd like to see a second category of ebike allowing higher power, could be subject to holding a license road use only etc but not requiring registration. 250w with Hobart hills and a load is a joke. May as well not bother.
In other news I just saw a tesla p85d in Hobart- couldn't believe my eyes... it wouldn't get out of my way- ha I was driving an ambulance under lights at the time. :mrgreen: probly the only time I'll overtake one!
 
i have some experience with those tassie hills around hobart.....on an ebike........I know where you are coming from,
they are exceptionally steep in places, I think quite a challenge to the best of ebikes.
250 watts continuous( 750watt peak) is not much help on those hills, I was using a gearless motor when I lived there and had to walk up many hills, a cyclone motor via the gears would pull up those hills, but pretty hard on the chain/gears etc.
 
this webpage:
http://www.micromo.com/technical-library/dc-motor-tutorials/motor-calculations
near the bottom has an example of using temperature limitations of a brushless motor to determine peak power ( in this case its peak amps), I'll just cut and paste their example so its saved. How to relate peak and continuos power is always problemmatic, so heres a way to do it.

Thermal Calculations

A current I flowing through a resistance R results in a power loss as heat of I2R. In the case of a DC motor, the product of the square of the total motor current and the armature resistance is the power loss as heat in the armature windings. For example, if the total motor current was .203 A and the armature resistance 14.5 Ohms the power lost as heat in the windings is:

power loss = 0.2032 x 14.5 = 0.59 Watts

The heat resulting from I2R losses in the coil is dissipated by conduction through motor components and airflow in the air gap. The ease with which this heat can be dissipated is a function of the motor type and construction. Motor manufacturers typically provide an indication of the motor’s ability to dissipate heat by providing thermal resistance values. Thermal resistance is a measure of the resistance to the passage of heat through a given thermal path. A large cross section aluminum plate would have a very low thermal resistance, for example, while the values for air or a vacuum would be considerably higher. In the case of DC motors, there is a thermal path from the motor windings to the motor case and a second between the motor case and the motor environment (ambient air, etc.). Some motor manufacturers specify a thermal resistance for each of the two thermal paths while others specify only the sum of the two as the total thermal resistance of the motor. Thermal resistance values are specified in temperature increase per unit power loss. The total I2R losses in the coil (the heat source) are multiplied by thermal resistances to determine the steady state armature temperature. The steady state temperature increase of the motor (T) is given by:

Tinc = I2R x (Rth1 + Rth2)

Where:

Tinc = temperature increase
I = current through motor windings
R = resistance of motor windings
Rh1 = thermal resistance from windings to case
Rh2 = thermal resistance case to ambient

For example, a 1624E009S motor running with a current of 0.203 Amps in the motor windings, with an armature resistance of 14.5 Ohms, a winding-to-case thermal resistance of 8 °C/Watt, and a case-to-ambient thermal resistance of 39 °C/Watt. The temperature increase of the windings is given by:

T = .2032 x 14.5 x (8 + 39) = 28°C

If it is assumed that the ambient air temperature is 22°C, then the final temperature of the motor windings is 50°C (22° + 28°).

It is important to be certain that the final temperature of the windings does not exceed their rated value. In the example given above, the maximum permissible winding temperature is 100°C. Since the calculated winding temperature is only 50°C, thermal damage to the motor windings will not be a problem in this application. One could use similar calculations to answer a different kind of question. For example, an application may require that a motor run at its maximum torque without being damaged by heating. To continue with the example given above, suppose it is desired to run motor 1624E009S at the maximum possible torque with an ambient air temperature of 22°C. The designer wants to know how much torque the motor can safely provide without overheating.

The data sheet for motor 1624E009S specifies a maximum winding temperature of 100°C. Since the ambient temperature is 22°C, a rotor temperature increase of 78°C is tolerable. The total thermal resistance for the motor is 47°C/Watt. By taking the reciprocal of the thermal resistance and multiplying this value by the acceptable temperature increase, the maximum power dissipation in the motor can be calculated:

P = 78° x 1 Watt/47° = 1.66 Watts

Setting I2R equal to the maximum power dissipation and solving for I yields the maximum continuous current allowable in the motor windings:

I2 = 2.19 Watts / 14.15 ohms
I2R = 2.19 Watts
I = .338 Amps

The motor has a torque constant of 1.86 oz-in/A and a no-load current of 60 mA. Therefore, the maximum current available to produce useful torque is .530 Amps (.590 - .060), and the maximum usable torque available (M) is given by:

M = .327 A x 1.309 oz-in/A = 0.428 oz-in

The maximum allowable current through the motor windings could be increased by decreasing the thermal resistance of the motor. The rotor-to-case thermal resistance is primarily fixed by the motor design. The case-to-ambient thermal resistance can be decreased significantly by the addition of heat sinks. Motor thermal resistances for small DC motors are usually specified with the motor suspended in free air. Therefore, there is usually some heat sinking which results from simply mounting the motor into a framework or chassis. Some manufacturers of larger DC motors specify thermal resistance with the motor mounted into a metal plate of known dimensions and material.

The preceding discussion does not take into account the change in resistance of the copper windings as a result of heating. While this change in resistance is important for larger machines, it is usually not significant for small motors and is often ignored for the sake of calculation.
 
whatever said:
this webpage:
http://www.micromo.com/technical-library/dc-motor-tutorials/motor-calculations
near the bottom has an example of using temperature limitations of a brushless motor to determine peak power ( in this case its peak amps), I'll just cut and paste their example so its saved. How to relate peak and continuos power is always problemmatic, so heres a way to do it.

Thermal Calculations

<snip>

That's not quite relevant to the Aussie 250W limit. First, I should point out that no one in Australia can realistically achieve legal compliance with the 250W limit, unless the bike is from Europe. While not impossible, it's impractical to achieve the testing requirements under EN15194 as is necessary under Australia law... Yes, our lawmakers are idiots and the whole electric bicycle thing was determined by people who really didn't care about or understand electric bicycles.

Anyway, assuming you ignore that ( because it's not like the authorities care anyway ) under EN15194, you can achieve any peak current on a system, declare the maximum as 250w, and all you need to do is make sure that there's absolutely zero propulsion power at 25 kph, and that's about it. So, as an example, if you want to have 20kW at 22kph and 0kW at 25kph, with a linear drop in power from 22kph to 25 kph, that pretty much complies.

Using this method, as well as plastering self-made EPAC stickers on everything, you could complete all the tests so that, generally, if they tested it would appear to comply with the law, and will give you plenty of peak power for climbing hills in Tassie at just under 25 kph.

I just use the 200w standard, but then I don't like pedalling so I use a throttle. But if anyone does want to make a 250w Pedelec, then there's many ways to verify "maximum power" under the standard that are pretty easy at least to comply with, and if you video'ed yourself doing that, you'd probably have a reasonable case in court just in case you did manage to upset mr Plod and he took issue with your bike.

As for most of the electric bikes I see in Australia? The majority visibly don't comply, but no one seems to care.

David.
 
cj7hawk said:
As for most of the electric bikes I see in Australia? The majority visibly don't comply, but no one seems to care.

David.

I think that really speaks volumes about the laws. People don't care about non-compliant electric bikes, because while most would well exceed the 200/250w limitation, few are so outrageously overpowered, that people would notice by the naked eye. The speed I can achieve with my electric bike is slower than what I can sprint on my road bike for a minute or so at least.
 
There's no such thing as "overpowered". :twisted:

1. I can't believe you guys haven't gotten that law changed yet. Why let pedalists, who are generally quite prejudiced against ebikes, make your rules? To get lawmakers on my side I would approach from the standpoint of that it's opposition to the greater good to discourage the use of a 0 emissions vehicle that is also the most efficient form of personal transportation developed by man.

2. If compliance becomes enforced, then set your bike up for 250W output from near zero rpm. At just a few kph 250W out is actually quite a lot of torque.
 
John in CR said:
There's no such thing as "overpowered". :twisted:

I'm happy to say there's no such thing as overpowered, if you can agree there are people who are undercontrolled.

I used to race 10 second cars - both drag and rally. Thats without nitrous. Every man and his fulleh sick yuleh brother used to want to race me on the street. It was pretty easy to see who were serious racers and who did the hack jobs. Once I chose not to race on a wet road after it had stopped raining. The other guy lost control from launch and slammed into the median strip which was high enough to stop his lowered car (probably from chopped springs rather than lowered properly). Checked he was okay and then just laughed and drove off.
 
Sunder said:
John in CR said:
There's no such thing as "overpowered". :twisted:

I'm happy to say there's no such thing as overpowered, if you can agree there are people who are undercontrolled.

I used to race 10 second cars - both drag and rally. Thats without nitrous. Every man and his fulleh sick yuleh brother used to want to race me on the street. It was pretty easy to see who were serious racers and who did the hack jobs. Once I chose not to race on a wet road after it had stopped raining. The other guy lost control from launch and slammed into the median strip which was high enough to stop his lowered car (probably from chopped springs rather than lowered properly). Checked he was okay and then just laughed and drove off.

Problem is, those kind of people lose their license after a while, then get on 2kW bicycles, and ride them through heavy pedestrian traffic at about 50 kph. The issue this creates for us is that most people see that as what we want extra power for, so politicians aren't likely to be on side. They're happy to ignore electric bicycles that go under 30, because no one really cares if they are legal or not, and would even ignore the fast ones if they could, but will never legalize them for that reason.

When the laws changed, they discussed the US 750W limit, and the Euro 250W limit. In the end, they didn't go for a limit at all - they just said EN15195 bikes are OK. In law. It was an absolutely stupid idea - but if you keep in mind they just wanted to make the bikes posties and other government workers use legal, it's all they needed to do. So we got stuck with all this legal stupidity. It was about protecting their mates who imported the bikes that didn't comply with Aussie laws - nothing more, nothing less. It certainly wasn't about helping cyclists ( or power cyclists ) - though I'm fortunate to live in a state where they do care about stuff like that.

Also, electric bikes at 250w full power are VERY range limited, because legally you can't stick a bigger battery on them - which makes them very short range - so Pedelec range is just 10km ( half-trip). Yeah, I know people on this forum will disagree with me, but it's pretty black and white. Euro-crap bikes only come with small batteries. 10Ah is considered "Massive" and is only ever an option with these sort of bikes - usually it 6-7Ah @ 24v or 36v. Not enough to get around in a hot country. And because the resellers do have to comply ( or at least appear to comply ) no one will be bringing in any extended batteries from euro-manufacturers and DIY kits are illegal, so only home-brew people will ever get around this.

I get around it with a small generator - 4kg of generator gives me all the power I need, up to 1kW continuous and the way I built it complies with both the 200W and 250W EN15194 rules, so I get extra range, and it's cleaner than WA based coal electricity, even with the massive inefficiencies I get from using a very small petrol motor. Not to mention the amount of power I waste on having high intensity lights wired permanently up to the circuit.

But the rear-wheel is still only 200W. I went 200W because most of the time, it's faster. All I need to do is keep increasing the voltage to the motor while adjusting the maximum power available, and as long as I have a tailwind or favorable gradient, I can use it - And because it's throttle, I can stop pedalling on hot days and avoid sweating altogether when I need to. Because you still sweat on a Pedelec which is why the no-sweat range will only ever be around 10km.

But I live in a flat area... I'd be a little more miffed if I had to deal with Tasmanian hills. I do have hills to deal with, but they are all behind me and only affect leisure riding.
 
John in CR said:
There's no such thing as "overpowered". :twisted:

1. I can't believe you guys haven't gotten that law changed yet. Why let pedalists, who are generally quite prejudiced against ebikes, make your rules? To get lawmakers on my side I would approach from the standpoint of that it's opposition to the greater good to discourage the use of a 0 emissions vehicle that is also the most efficient form of personal transportation developed by man.

We're the country with mandatory bicycle helmet laws (despite the fact that it has a net-negative effect on population health). I doubt they're going to legalise our ebike hot-rods and Stealths anytime soon.
 
Architectonic said:
John in CR said:
There's no such thing as "overpowered". :twisted:

1. I can't believe you guys haven't gotten that law changed yet. Why let pedalists, who are generally quite prejudiced against ebikes, make your rules? To get lawmakers on my side I would approach from the standpoint of that it's opposition to the greater good to discourage the use of a 0 emissions vehicle that is also the most efficient form of personal transportation developed by man.

We're the country with mandatory bicycle helmet laws (despite the fact that it has a net-negative effect on population health). I doubt they're going to legalise our ebike hot-rods and Stealths anytime soon.

Youve never been hit before.... Helmets save lives. I'd have brain damage and a large portion of my scalp across the road if I didnt have a helmet.
 
Raged said:
Architectonic said:
John in CR said:
There's no such thing as "overpowered". :twisted:

1. I can't believe you guys haven't gotten that law changed yet. Why let pedalists, who are generally quite prejudiced against ebikes, make your rules? To get lawmakers on my side I would approach from the standpoint of that it's opposition to the greater good to discourage the use of a 0 emissions vehicle that is also the most efficient form of personal transportation developed by man.

We're the country with mandatory bicycle helmet laws (despite the fact that it has a net-negative effect on population health). I doubt they're going to legalise our ebike hot-rods and Stealths anytime soon.

Youve never been hit before.... Helmets save lives. I'd have brain damage and a large portion of my scalp across the road if I didnt have a helmet.

I was T-boned by a car on a bicycle. A bike helmet saved my life and could be proven to have done so. But even so, I agree that MHL increases ( not decreases ) rider risk level and the helmets that are mandated are just dangerous.

I pick and choose my bicycle helmets very carefully, and technically, the ones I do choose are illegal, but I would not wear a legal helmet on a bicycle because they are dangerous. Mandatory helmet law helmets also lead to deaths where there would be no death if the helmet was not involved. They are a good example of best-intentions leading to a worse outcome due to the demonstrably poor knowledge of cycling by those who made the decision in the first place, based only on experience with impact-related injuries sustained while cycling. Even neurosurgeons are split on the topic of whether they do more good or harm.
 
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