Q100 at 50-60v

[bluovalguy]

Finally have put some miles on my bike since the weather has been nice. It's a Diamondback Edgewood 700c hybrid. Went with the rear drive 36v slow wind Q100 kit from elifebike. I hid a 3 speed switch on the bottom side of the controller box, and a switch on the side for cruise control. Set up a $14 watt meter which can be velcro'd to the seat post with the same anderson connectors between the battery/controller. I believe this controller is the KU65 equivalent, stock was 12a which was pretty weak. Soldering the shunt to 18a helped, but with a 40v Greenworks battery it was too slow... wouldn't go much over 18mph. Now am running with Ryobi power tool batteries in series, for 55v nominal/ 62v fully charged. With these 4 batteries it's basically a 15s 8ah 18650 pack (more details on the batteries linked below.) Tested briefly still at 18a and it ran great, but dialed it back to 14-15a for less strain on the motor.

Greenworks- http://endless-sphere.com/forums/viewtopic.php?f=14&t=55790
Ryobi- http://endless-sphere.com/forums/viewtopic.php?f=14&t=56505


This thing is a blast with the extra voltage. With the 3 speed switch on high it cruises at 25-27mph. It got up to 30 the other day with moderate pedaling and a tail wind. It feels like it's still providing assistance into the low-mid 30's going down hills. With the switch on mid it goes about 20-22 which is perfect most of the time... pulling 5-10 amps for a range of about 20 miles. Low speed is similar to running on the 40v batteries only, 17-19mph with a bit more range. It has enough torque to maintain about 15mph up moderate hills, but I have to pedal hard to keep 10mph up the really steep hills.

Has anyone else run this high of voltage reliably over time? I understand with this controller it should really be kept below 60v (63v caps), but I haven't had any problems with it yet. Also the motor seems pretty happy, it barely gets warm unless it's really bogged down for awhile. It doesn't seem to groan any worse up hills with the higher voltage, just faster. I will make sure to post back if anything blows up. I do have a spare controller/motor.

Just wanted to share my experience, since I was skeptical about the performance of the small geared motors. I didn't want a huge geared motor or direct drive for the stealth and weight issues, and this ended up working out well.

 

[motomech]

You might want to check the calibration of your speedo. Your top speed numbers are at least 10% higher than than the rest of us get with a single Cute.
The weak link with the Q100 system is the Hall circuit, so keep your Amps at 14A and you will be ok. Check for controller heat and ck. the hall bullet connecters every now and then. Mine started to melt at 12S and 22 Amp.

 

[fellow]

Wow, Q100 and 15s lipo is brave! I've tested my Q100H 201rpm@36V_nominal at 13s LiPo (48V/14A), its at ambient temperature no matter what (its oil cooled). It feels pitty to keep it that cool, almost waste of resources! It pulls nicely up to 30km/h (26" wheel). How was the temperature at 15s and 18A?

I understand with this controller it should really be kept below 60v (63v caps)

You need 100V capable mosfets and probably capacitors too for reliable 48V systems, according to Fairchild Power Seminar 2006:

The voltage rating of the MOSFET must be larger than the bus voltage Vdc. Allow safety margin for:
• Bus voltage variations
• Input voltage spikes
• Ringing in synchronous buck
• Motor drive spikes
• Flyback transformer spikes
• Change in VDS at low temperature
• Change in VDSwith negative VGS drive

Typical MOSFET voltage ratings:
24V motor drive 60V
48V system 80-100V
80V system 150-200V

 

[bluovalguy]

You might want to check the calibration of your speedo. Your top speed numbers are at least 10% higher than than the rest of us get with a single Cute.
The weak link with the Q100 system is the Hall circuit, so keep your Amps at 14A and you will be ok. Check for controller heat and ck. the hall bullet connecters every now and then. Mine started to melt at 12S and 22 Amp.

Just went for a cruise and verified my speedo is accurate (to my phone gps anyways.) I think a factor that I was underestimating though is wind. You never notice it until its blasting you in the face. Will need to test again on a calm day, but best I can tell from going in both directions on the same stretch it should be able to do 26mph with zero wind on a full charge.

Also found that it's usually just over 14a under load, but occasionally peaks at ~15.5. Think I should dial it back some more?

Wow, Q100 and 15s lipo is brave! I've tested my Q100H 201rpm@36V_nominal at 13s LiPo (48V/14A), its at ambient temperature no matter what (its oil cooled). It feels pitty to keep it that cool, almost waste of resources! It pulls nicely up to 30km/h (26" wheel). How was the temperature at 15s and 18A?

I understand with this controller it should really be kept below 60v (63v caps)

You need 100V capable mosfets and probably capacitors too for reliable 48V systems, according to Fairchild Power Seminar 2006:

It never got hot at 18a, but I was very careful to pedal hard on all hills and never let it load down. I just checked the FET's on my spare controller and they are RU6888R, rated for 68v. Also noticed that only one of the caps is 63v, a medium sized one. The big one and several of the smaller ones are 50v... will see if it holds up.

Did you have to do anything special to seal up the motor when adding oil? Very cool set up with your batteries in the frame by the way!

 

[fellow]

Thank you, your bike is very clean looking too. It's always nice to see people daring to say NO to visible duct-tape . I just used this

to inject 100ml of ATF oil via one of the six disc screws. Sealed the 6 screws with automatic gearbox grade silicone, and allowed it to expand/beathe thru the wire hole and bearings. It drips at rare ocations thru the bearings, mostly when I lean the bike on the side(not all the time). I think it's charming with oil driping electric bike. No police officer would embarass himself accusing one oil dripper of being e-biker . When pulled over, I always explain to the officer that lubricating is the secret of my effortless pedalling .

 

[bluovalguy]

Thank you, your bike is very clean looking too. It's always nice to see people daring to say NO to visible duct-tape . I just used this

to inject 100ml of ATF oil via one of the six disc screws. Sealed the 6 screws with automatic gearbox grade silicone, and allowed it to expand/beathe thru the wire hole and bearings. It drips at rare ocations thru the bearings, mostly when I lean the bike on the side(not all the time). I think it's charming with oil driping electric bike. No police officer would embarass himself accusing one oil dripper of being e-biker . When pulled over, I always explain to the officer that lubricating is the secret of my effortless pedalling .

Haha! Nice!

 

[DAND214]

Question is. Are you running 4 packs or 6 packs? You say 4 Ryobi 18v and they are 4Ah each. They are 5s2p packs. So where does the 15s come in?
Sorry but I don't understand.


Dan

 

[bluovalguy]

I just checked the FET's on my spare controller and they are RU6888R, rated for 68v. Also noticed that only one of the caps is 63v, a medium sized one. The big one and several of the smaller ones are 50v... will see if it holds up.

Now I'm concerned about this. Looked at the big 50v cap closer and it's coming right off the main +/- inputs, so it's definitely seeing 62v at full charge. Then there's the 63v medium sized cap, 5 other smaller 50v caps, one 26v and 1 16v (these 2 are probably fine, only seeing reduced voltage.) How do these usually fail? Is it possible that it would produce a short across the main +/-?

 

[bluovalguy]

Question is. Are you running 4 packs or 6 packs? You say 4 Ryobi 18v and they are 4Ah each. They are 5s2p packs. So where does the 15s come in?
Sorry but I don't understand.


Dan

2 parallel Greenworks in series with 2 parallel Ryobis. Greenworks is 10s2p 4ah (37v nominal) and Ryobi is 5s2p 4ah (18v nominal.)

 

[DAND214]

Ok that solves the nystery.

I guess I go back to my Cute and dump the MACs, NOT!

Dan

 

[bluovalguy]

Finally got around to replacing all the 50v caps with 63v. The speeds I posted earlier are legit. On a full charge it averaged 25.0mph in 1 direction and 28.5 in the other.