I'd like to check the Wattage on an electric hub motor. The maker claims it's 1000w, I'm not convinced. Do I need to by-pass the controller to place the multimeter into the circuit? I'm not getting a reading as it is, but don't want to risk damage to anything.
Measuring Amps on a Multimeter
- Thread starter HughMorris
- Start date
It may be capable of a 1000W but not actually reach that amount, mine is 250W "rated" and is quiet happy at 600-700w for brief periods, maybe link the kit in your next post. The main way to check watts is via an LCD screen on the handlebar most have this function, what model LCD if any are you using? What amps is the controller and the battery voltage?
If the motor is rated at 1000W, this is the 'maximum continuous rating' and is nothing to do with what the motor actually draws. It is merely the maximum continuous wattage that the motor can take without overheating.
The controller maximum current will tell you more about the nominal wattage delivered to the motor. ie If the controller rating is 20A and the battery is 36v then the nominal max wattage is 720W - so long as the battery is capable of delivering 20A.
If you are disappointed with the performance of your motor it's because it is probably a direct drive motor rather than a geared hub. They are power hungry, inefficient and crap on hills.
A 250W geared hub will take the same 720W but use it far more efficiently, so less of your precious battery capacity going into generating heat.
The controller maximum current will tell you more about the nominal wattage delivered to the motor. ie If the controller rating is 20A and the battery is 36v then the nominal max wattage is 720W - so long as the battery is capable of delivering 20A.
If you are disappointed with the performance of your motor it's because it is probably a direct drive motor rather than a geared hub. They are power hungry, inefficient and crap on hills.
A 250W geared hub will take the same 720W but use it far more efficiently, so less of your precious battery capacity going into generating heat.
Thanks for your responses guys. I was comparing performance to my 750w geared mid-drive ebike, and now understand my disappointment.
The kit is attached to a TrikkeT12, trike. I thought it would be fun to fit a Dualmoto electric scooter hub to it. No LCD, just throttle. Chinese writing on controller so don't know the amp rating but they claim 1000w. Battery is 48v. Goes well enough on the flat but dies on hills as you say. Great forum this.
The kit is attached to a TrikkeT12, trike. I thought it would be fun to fit a Dualmoto electric scooter hub to it. No LCD, just throttle. Chinese writing on controller so don't know the amp rating but they claim 1000w. Battery is 48v. Goes well enough on the flat but dies on hills as you say. Great forum this.
Sadly you are very far from the first to be caught out by these direct drive hubs, and won't be the last. Good you've got your other bike anyway.
I was lucky (careful?) enough to read this forum for a few months before first committing to anything (a Woosh XF07 hub) otherwise I would almost certainly have fallen for one. (As it is, I don't actually have first hand experience of how bad they are, just the word of all the posts here.)
Scooters have smaller wheels, so the motor is effectively geared down.
Efficiency is one of the main characteristics that affects hill-climbing. A motor has a maximum rpm that depends on how it's wound and what voltage you give it. At 75% of the motor's max rpm, it'll have an efficiency of about 75%. At 50% of max rpm, that drops to about 60% to 65%. Below that, the efficiency accelerates downwards to something like 30% at 25% of max rpm.
Let's say that you have a 25 amp controller and a 48v battery, so you can get a max power from the battery of 1200w. Let's also say that your motor can spin to 40 mph. At 10 mph, it would produce 30% x 1200w = 400w.
If you put a cheap wattmeter between the battery and the controller, you can see how much power is going into the controller all the time, which is very interesting, but you need to know tyour speed and tge motor's efficiency curve to determine how much output power you're getting.
If you have a look at www.ebikes.ca/simulator, you can enter detaols about your system and see how it should behave in different circumstances.
It'll work exactly the sane as a scooter then if you use the same voltage and current, with adjustment for mass.
Is there another way to power this trike then? How about a go-kart motor, chain driven on to a rear axle.
OK. Well I'd be starting from scratch. The trike is a standard American Trikke T12 model. As you probably know these were designed to be used with a 'carving' side to side motion. I'd like to fit a motor to power the trike to avoid this, either to front wheel or rear wheels on an axle ,or both! Just a thought. Any ideas? If not I'll sell it .
How about showing the forum pics of what you have, otherwise we will not waste time looking up something you are too lazy to post.
You really are up yourself Nealh. You kicked this off, calling me lazy. I'll sort it out myself. Who needs you, dick.
The first three "Trike" images that Google gives me (excluding toys and pushchairs) are:
The second one obviously isn't like yours, but how about either of the other two?
Honestly, people on here are keen to help, but you have to give us more to go on than "TRIKE!!!".
Any one who comes on here asking for help and then can't be bothered to upload a pic of a specific bike they have is as I said just being lazy and doesn't deserve further help, esp if going to insult or abuse forum users willing to offer up free and helpful advice. If you are upset by being called lazy then one needs to grow up, throwing insults is not very adult behaviour esp as others may also decide to ignore pleas of help.
Trikes and bikes all vary and have their difference's, not everyone can be taken with a pinch of salt to convert.
Trikes and bikes all vary and have their difference's, not everyone can be taken with a pinch of salt to convert.
Related Articles
-
Swytch announce new conversion kit with ‘pocket-sized’ battery- Started by: Pedelecs
-
New Swytch launches on Indiegogo, raises £100k in first hour- Started by: Pedelecs
-
Swytch to unveil 70% smaller, 50% lighter conversion kit- Started by: Pedelecs