JTL
10 W
I don't currently have any kind of watt meter. Do most ebikers have one? I don't want or need a CA but I was thinking about an ebay cheapo or a less cheapo Watts Up. Any suggestions?
Ykick said:On my simple bikes, after I’ve learned their power usage it really isn’t gonna change much. Therefore, I temporarily insert RC type type power meters, ride for a while and observe what the system does. Perform any tweaks needed and eventually just remove the meter and put it back on my charger station.
Be aware inserted power meters will require connector ecosystem. That’s something to consider along with your choice of power meter. Good solid power connections and wire make it all possible.
dogman dan said:The cheap blue watt meters cost about 12 bucks these days, and are quite adequate if you don't want to mount it on the bars. It sounds like a pain to stop to look at it, but really it's not.
A bar mounted watt meter like the CA, is still the only way to go for learning to ride the bike for max distance. Not really max efficiency, but max combination of speed, your pedaling, the terrain and weather, etc, to go farther. The ca does a continuous watthours per mile display, that is priceless when you need maximum range, without going to maximum pedaling effort.
You can of course stop, look, and make the mental calculations as you go, with a cheap blue meter.
JTL said:Do you monitor the info while you are riding? I think I read that some of the cheap meters have a problem with accurate data if the meter is not real close to the battery. It would be nice to be able to monitor the charger. Thanks
JTL said:I don't currently have any kind of watt meter. Do most ebikers have one? I don't want or need a CA but I was thinking about an ebay cheapo or a less cheapo Watts Up. Any suggestions?
Ykick said:JTL said:Do you monitor the info while you are riding? I think I read that some of the cheap meters have a problem with accurate data if the meter is not real close to the battery. It would be nice to be able to monitor the charger. Thanks
Long power wire is the problem for remote mounting, not what you pay for the meter. Use large enough gauge wire and good connectors 3-4ft wire isn't gonna make significant difference.
However, once you go through all of that trouble you'll probably find the RC power meters are too small to read under most riding conditions. Even the slightest vibration makes them very difficult to see under way.
You might be missing what they're designed to do? RC power meters are often installed temporarily into planes or RC vehicles then sent out to fly or do what they do. When they return, you make note of min/max and amount values for that particular mission.
That's how I use RC power meters on my simple ebikes. Insert in a logical place, usually near the battery, go ride and retrieve pertinent info when stopped.
Is that ideal? Maybe not? That's why we've got the CA (cycle analyst) for an actual dashboard that provides the power data and more. Using a compatible controller and DP (direct plugin) CA you won't even need to bother with power wiring and connectors. But, it does come at a price well above that of RC power meters.
dogman dan said:FWIW,, I did open up and tweak my cheap wattmeter, so it read voltage correctly. The watts seemed ok compared with known to be calibrated CA. I don't recall if that can be adjusted inside those cheap meters or not. I only had the one, and it died in a few months. ( I fed it 72v by mistake once) Now I have 4 CA's, so usually I have one on every bike up and running.
To get your fuel gauge, you first charge full, then discharge by riding till it's 100% empty. when the bms stops it, If you have one. Watch at the end, when the battery cuts off, you lose your data on the cheap meter.
Now you know your real world AH or WH. For the way you ride, on your bike. Your 10 ah pack may put out 9.2 ah, or whatever. Now you know what half a tank is, etc. Half of 9.2 is 4.6ah. Or call it 8 ah, and know if you turn for home with 4 ah used, you make it with a big reserve.
The meter will display AH used, it will display watts currently flowing, it will display WH used. It can read the battery flow going out, or you can put it on a charger and read what's going in. Just a matter of plug compatibility to do that. Make adapters for the charger plug is the best way to go, unless it's just a naked pack.( no bms).
Once you know what your performance is,, like Ykick says, you don't need it on the bike anymore. I hardly need my CA to know I'll make the usual 10 mile round trip to the grocery for example. But I sure love a CA when I'm planning a ride of 40-80 miles. 99% of what I use my CA for is knowing I did actually charge the battery. Hey,, lookee there, 54.6v. Before I had any watt meter, I got screwed a few times by poor plugs on chargers. Ride off thinking I had 15 ah, only to find out 10 miles from home I'm empty. Whoops. That's 10 miles all uphill, from home. :lol:
KINNINVIEKID said:I found that the cheap blue meters never lasted very long but the GT power meters have done a couple of years so far.
They were on my bike for 18 months till I bought a CA and since then are connected to my bulk charger.
http://www.ebay.co.uk/itm/G-T-POWER...124881?hash=item4654f61811:g:5LIAAOSwTA9X2Q0h
motomech said:The Wattmeter needs to placed in series between the batt. and the controller, not paralleled.
I have had about every kind of instrumentation from a CA on down and these days I just use a Voltmeter, it's all I need w/ LiPoly, as it's discharge rate is very linear..
W/ a new controller, I'll temporarily install a Wattmeter to ck. the performance of the controller.
The thing about meters, if they are LED, they need a way to turn them off, either at the batt. or at the meter or it will deplete the batt.. LCD meters that have back lighting, need to have a way to turn off the light.
Luna Cycles is a good source for meters, I really like their flat Voltmeter.
Here are two of them(I have two packs)in a clear pouch on a sm. over-the-frame bag. Push a button and they lite for a minute or so. The LCD display doesn't draw enough to be factor;
motomech said:Sorry, maybe I should have said in-line;
Red from batt. into meter red, red from meter, to controller red
blk. from batt. into meter blk., blk. from meter to controller blk.
No, the pre-charge resistor is in the female side marked with the green markings. It will function properly with the non-S male XT90.JTL said:If I put a meter inline between the battery and the controller I could simply unplug it and reconnect my wires direct without the meter when I don't need it. I have an extra xt90 set but they are not the "s" style. My battery to controller connection will have the "s" style according to em3ev and they insist on keeping it that way. My guess is that if I use a non-s male into an "s" female I will negate the pre-charge feature. Is that a fair guess?
Jon NCal said:No, the pre-charge resistor is in the female side marked with the green markings. It will function properly with the non-S male XT90.JTL said:If I put a meter inline between the battery and the controller I could simply unplug it and reconnect my wires direct without the meter when I don't need it. I have an extra xt90 set but they are not the "s" style. My battery to controller connection will have the "s" style according to em3ev and they insist on keeping it that way. My guess is that if I use a non-s male into an "s" female I will negate the pre-charge feature. Is that a fair guess?