CroBorg Super Commuter

The Sunday Ride consumed 12.1 amp-hours at about 68 volts which is 825 watt hours. Length was about 22 miles so about 37 watt hours per mile. This ride has lots of hills and we varied the pace from 20 to almost 40 mph. Consumption on the HS3540 was, if I recall correctly, just a bit more than the Cromotor. They were less than 10% apart in energy consumed. At the halfway point the Cromotor was further below the consumption of the Xlyte, but toward the end of the run I made a speed run that pushed the efficiency down a bit and reduced the difference. I don't think we have enough data to be sure, but it looks like the Cromotor may be slightly more efficient than the Xlyte. Maybe.

I'm basing this on the Hyperion charger's charge data. It was 12.1, 12.2, 12.1 amp hours in each of the three banks. I'm still calibrating the CA so it was less accurate and on this day it was reading a bit high.

One nice thing about the RC chargers is the charge data they give. When I use a bulk charger I don't get all the nice data. Wish the bulk chargers had more info. We could add that instrumentation to them, of course.

I would venture to say they are likely closer than 10% on our ride- I was on average riding slightly faster than Alan- (during the first part of the ride I was ahead and riding a bit faster- the consumption gap widened- during the later part of the ride I was following at similar speed and the consumption gap narrowed)... as well my battery voltage was 5-10% lower than Alan's--- I wouldn't take any particular conclusions from this comparison.

And as for what motor is more efficient overall, or in any given setup- that depends on so many factors of the individual setup. The HS motor is not a particularly inefficient motor... any motor "eats energy" when you ride fast or out of it's most efficient operating region... I'm kind of unhappy with the high consumption of my bike but I know it's due to its heavy weight and high speed rather than the motor in particular.

I charge using a stand-alone CA on my "pile of power-supplies" charger. Simple as that. Haven't used the Hyperion in months... The hassle of charging sub-packs in stages is something you won't miss if you switch. Use Methods HVC for safety, put the charger on a count-down timer switch if you don't want to unplug it at the end of charge- Done. Start it charging once, come back and it's full. No buttons, beeping, menus, crappy JST connectors... Ok, I've obviously got an axe to grind.

I would have to agree with Henry, the differences here are too close to definitively call in terms of motor efficiency. The Kokams seem to have lower operating voltages than the Turnigy, though I thought it was a couple of volts (at 18S) which is about 3%. I was carrying more weight and perhaps more air resistance, and I chose to climb the last big hill a bit slower. I didn't pedal as much as Henry, though a lot of the pedaling was faux anyway. Lots of little differences, so hard to say how they all stack up. For certain they are not widely different in the efficiency department. The Kv's also differ by only 8%. The max torque capability is perhaps the largest difference, and if other things are equal (they may not be) the 35mm width of the HS compares to the 50mm width of the Cromotor for a 43% increase in torque and power potential. I don't think either of our setups are pushing the envelope there, I'm running 40 amps with a 12 FET, not sure what Henry is running.

My goal with this build at the moment is to have the capability to be able to either bulk charge or balance charge. I won't start bulk charging until I have more cycles on the pack.

I have two bulk chargers, one of them doesn't seem to be doing any charging when I test it, the other has worked well on the mountain bike.

To engage the protection of the installed Methods boards for bulk charging I need to do more wiring and put a few more components on my board and test it.

Nice Weather Day

Today would have been a great day to commute to work on the Borg. But it wasn't compatible with my errands so I will see if tomorrow works better.

The seatpost rack should arrive today. That will make commuting easier as I need to carry a few things. I won't carry heavy stuff on a seatpost rack, but I don't have to most days. I have chargers staged at work already.

Bulk Chargers

The bulk chargers I have are BMSBattery alloy case, the 400W and 240W models. One seems to work fine (the 400W), the other doesn't seem to 'charge' though it is putting out voltage. Have to look at that further some time, but may want to get another bulk charger now. What other bulk chargers do folks recommend? I need to charge at 75V, I'm not reconfiguring the pack for charging. I don't need anything too super fast, just something boring and reliable.

I see the 900 watt BMSBattery has a better price per watt than other sizes. Unfortunately their shipping charges are horrendous. They don't have any reasonable priced shipping options.

Not bad 10% difference on the efficient, Have you compared the HS and CroMotor temperature? and I remember ilia told me that HS35 is limited 2500 watt continuous and can do run 4000 watt without damage the stator.

Jeremy (Zombiess) said CroMotor capable 4000 watt continuous. I guess there is some difference between HS and Cro.

Anyways, About the charger, I had BMSbattery's kingpower charger for my Yuba cargo bike (Headway 16S pack) and 2 or 3 months later the charger blew up my face (discovered FETs explode!). Never again, I don't trust BMSbattery anymore. Hyena (Jay) told me suggested get meanwell switch power supply included Kingfish recommended HRP-600 power supply and they are most reliable compare to BMSbattery charger.

I remember you was there when Kingfish visited in SF, I am sure you saw his HRP-600 powersupply and the HRP-600 is freaking AWESOME due it has auto shutdown (power off) when the battery reached 95% - I cant remember exactly Kingfish told me. I would avoid meanwell S350 or higher because they do not have auto shut feature like HRP has. Just not the reason bad charger but purpose for my safety since I am deaf guy cant hear the beep or sounds when it goes HICCUP restart again and again eventually lead overcharge. I afraid! :lol:

sorry long talkative 8)

I've heard good things about the HRP supplies, but they don't seem to make them in 75V versions.

I don't think series-ing up power supplies is a particularly good design.

Any other choices?

Yeah, HRP can re-adjust voltage limit and 2 series supplies will do the job 75v. I assume you wanted just portable easy carry travel anywhere with you?

GCinDC bought some bunch of laptop chargers 24v? (not sure what exact volt) and series'em up 84V purpose for his office use power outlet without hassle using iCharger at work. You might want ask Greg (GCinDC).

otherwise all I can think of is BMSbattery charger but hate their reputation lousy quality control components.

chroot said:

Not bad 10% difference on the efficient, Have you compared the HS and CroMotor temperature? and I remember ilia told me that HS35 is limited 2500 watt continuous and can do run 4000 watt without damage the stator.

Jeremy (Zombiess) said CroMotor capable 4000 watt continuous. I guess there is some difference between HS and Cro.

Click to expand...

Woah hold-on here. These motors are not "10% different". As I wrote above there are too many confounding factors affecting the data from the ride Alan and I took the other day to make any conclusions about the motors. If quantitatively tested I believe we would find they are not likely more than a few percent different in peak efficiency.

Continuous/peak power ratings are also pretty useless on their own without more data. Factors such as hill climbing and wheel size are much more important to power rating than anything else. You could easily burn up the cromotor putting 1kw in if you're trying to climb an extremely long, steep hill in a 29" wheel.

I'm not trying to defend the HS motor, I don't think it's anything special, but then the cromotor is not some revolution either- it's just well made and BIG. 42% more stator and corresponding less end-turn loss. You can certainly get torque and power out of it well exceeding the capability of the H motor. I like the cromotor and think it's a pretty good deal for a good motor!

Mean well PSs are good stuff. If you want power density I like the RSP- compact but with loud fans. More compact than HRP (HRP is also loud). My personal favorite are the HLG IP67 LED power supplies- adjustable CC setpoint, silent, fanless, very efficient. They're sort of expensive per watt, and heavy and bulky (potted) but the silence is very nice. My 18s charging rig is 3*HLG320-24A. About 1kw. Only trouble with mean-well in general is that most product lines max out at 48v so for 18s you must have either 3*24v supplies or 1*48, 1*24. Maybe you can find a Delta-Q on ebay, they're big, powerful, well made, reliable... and not easily adjustable.

-H

@acuteaero - Don't worry, I can be wrong and I just based what the sellers stated in other thread. I wouldn't want run 29" wheel with the cromotor as Zombiess warned better off between 20-26" wheel for the longevity last. I understand your point.

acuteaero said:

...

Mean well PSs are good stuff. If you want power density I like the RSP- compact but with loud fans. More compact than HRP (HRP is also loud). My personal favorite are the HLG IP67 LED power supplies- adjustable CC setpoint, silent, fanless, very efficient. They're sort of expensive per watt, and heavy and bulky (potted) but the silence is very nice. My 18s charging rig is 3*HLG320-24A. About 1kw. ...

-H

Click to expand...

Thanks for mentioning these supplies. I think you may be onto something there.

Since I brought out the three 6S series sections of my pack in individual PowerPoles I could easily use three of the 24 volt supplies to bulk charge with, and not have to series the supplies, and not have the risk of charging an 18S string. I can put the PowerPoles into a 2x3 block and have a single connector to plug in. The supplies would be in series by virtue of the pack connections, but they would be independent themselves.

I may want to add some voltage/current monitoring, but that is easy enough.

Sure, that will work- but I don't think it's as good a solution as running the PSs in series outside the pack-

-You will have to carefully calibrate each supply to run the same voltage, if they drift unevenly over time or temperature you will end up with a different CV voltage on your three packs
-You can't just use one CA to monitor charge progress- I really like having the CA on during charge- instant readout of voltage, current (have we hit CV yet?) and Ah.
-You can't just use one HVC "breaker" if you want to run using methods' cell voltage HVC/LVC system, regardless with your head board or his.

What is your particular concern about running the PSs in series? I would maybe consider being concerned about stressing the DC isolation if we were running 100+ or 200+ volts, and if the power supplies were badly designed (they're not... I remember reading about some people's experience burning Soneil chargers when using them at top and bottom ends of a 150v+ EV pack...) but in practice the Mean Well supplies, as well as server supplies etc appear to take running in series like a champ. I have never had a single hiccup with either my HLGs or my RSPs.

First Commute



Inspiration Point, Wildcat Canyon

Yes, the covers are really that white.

The stars finally lined up and we made the first commute to work run with the new Cromotor powered Greyborg Warp.

Specs at this point:

18S4P 20AH 75.6V hot off the charger, 12 FET, set for about 35A and delivering about 40A and just over 3KW peak (very mild for this motor).

It made the run just fine, and consumed about 9 amp hours to traverse 13 miles and 1200 feet of climbing. The calibration of the CA is still off (even though I corrected it), these consumption figures are based on the charger's integrated current reading. Maintained mostly 15-25 mph, pedaled some but not enough to save much energy, just enough to get the blood pumping and warm up on a beautiful summer morning.

Checked the motor at the top at Inspiration Point and it was just barely detectably warmer than ambient. Pretty much no heating. After the ride an hour later it was just warm, sitting on the charger in the office as the heat slowly percolated out.

The Topeak QR beam rack MTX and trunk bag are pretty slick. Seem to stay put, and low enough to get a leg over if you remember it is there, the top of the trunk is just higher than the seat.

I like the way the big moped tires and suspension eat up the bad pavement. I can focus on watching the traffic and not have to worry so much about the road. You still have to keep watch on the surface, but little stuff just doesn't matter much.

The only exciting moments were the two times I scraped a pedal. I could use a longer shock or shorter crank arms, or just remember to avoid those situations - pedaling in a turn in one case, leaving the inside pedal down in another turn.

Commute Return Trip

The homeward commute was uneventful. Energy consumption was way down, the CA (which has been reading high) said 6.6AH. We'll see what the charger says. In any case we have enough energy in the 20 amp hour pack to make the round trip at these usage rates without recharging at work (or without recharging at home).





San Pablo Reservoir

Balance Charging



The pack is divided into three banks, each can be charged separately. Here the Turnigy 8150 is charging one bank at 7 amps.

Each of the three cable pairs leads to one bank. It took just over 2 hours to put 11.5 amp hours into each bank, so the charge time at work today was about 6.5 hours.

More Charging..

The first bank took 6641 mAH to charge from the Hyperion at 20 amps, which took 40 minutes. The Hyperion 1420i is pretty fast when you power it from a 24V 700W supply.

For a moment I thought the CA calibration was all of a sudden "on", but then I remembered that I forgot to reset the CA until I was a mile away, and that mile is pretty steep, so about 1 amp hour was missing from the reading. So the CA reading is more like 7.6 amp hours, and the charger only put back 6.6. So the CA is still reading high. So I need to adjust the shunt value.

So that is 68V * 6.6 AH for 350 watt hours divided by 13 miles is about 35 watt hours per mile.

Commute #2

Made another commute run today. Dug out the old D90 DSLR to carry on the ebike. Grabbed a few photos. Here's one along the lake, a nice spot to stop and take in the beautiful morning.



The first bank just finished charging. 9.1 amp hours in 102 minutes. Yesterday the battery was not fully charged when I set out, so it took more and longer. Today it is just from the ride in.

Banks took 9.1, 9.0, 8.9 ah charging.

The ride was more spirited, with a few high speed runs at 30+. I climbed a 12% grade at 25 mph with some hard pedaling.

One athletic biker was pedaling on a moderate uphill at about 20 mph where most folks are doing half that. Amazing rider. He didn't seem to want to chat though as I glided past at 25.

Hey Alan, nice bike! I have the exact same motor as yours on a different frame, What kind of freewheel is that? I have purchased 2 single speed freewheels and they wont fit One will not screw on all the way (so that its flush), and the other one has the right thickness but the diameter is too samll :?

It is a Dicta 16 tooth freewheel. Fits just about perfectly, no spacer. This is one of the previous batch of motors from late last year, so might be slightly different.

Very nice finished product! I love the heavier tires for the same reason, it just eats up road bumps and debris.


It almost looks like you could mount your soft bag in front of the seat on the top tube. Would you mind setting the bag on the top and taking a pic?

The Ride Home

Had a great ride home today. Beautiful weather, not as hot as yesterday, and I didn't have a too-warm jacket this time to slow me down. I played tag with some fast road bike pilots who chased me for miles along the lake. Actually I'm not sure they were chasing me at all, but they caught up to me on the downgrade by the dam and I had to accelerate downhill to stay ahead. They were running almost 40 down this grade and I was barely able to stay ahead of them there, I thought they were going to draft me, but the Borg left them behind. I let them pass a bit later, then I followed them a bit before turning off. It seems that at 70 volts and 3kw the Borg is enough to be competitive with high performance road bike riders downhill up to 40. Of course on the uphill or flat it demolishes them. It was fun. Big ebike grin.

The first battery bank has recharged and required 7.8 amp hours. This is about 40 watt hours per mile on the 13 mile run home with 600 vertical feet of climbing. Compare to about 70 wh/mi on the uphill run (1200 feet of climbing in 13 miles).

Most of the run I averaged about 20, with a few spurts to higher speed. Climbing the 10-12% road at the start it made 20 mph with some pedaling. I look forward to the 24 FET controller, it was noticeably stronger and can be dialed up more. Actually 20 mph on a 10+% gradient is fine, I just don't want to be at full throttle when I'm doing it.

Front Bag

Is this what you meant, John?

I like the first pick. Mount it like it was a gas tank it will shift the COG for better riding I think.

That particular bag is too wide for the rear location.

But it gives me an idea. For range extension make a forward saddle bag that holds batteries alongside. Three 6S 8AH packs on each side would give 18S 16AH bringing the total up to 2.4 KWH for a nice range extension. Leave the trunk rack for light stuff.

Actually it would be better to utilize the space between the front wheel and the frame. Lots of room there for extended range packs.

Trunk

One thing to keep in mind regarding the trunk and weight distribution. There are 24 pounds of batteries under the covers. 2/3 of them are under the upper cover forward, and 1/3 in the lower area toward the front of the space. So there is a lot of high and forward weight. Handling feels pretty good. Much more stable than the recumbent, for example, or the mountain bike.



The Trunk is for light stuff. Clothes, cellphone, camera. Probably about 5 pounds.

Today's inbound numbers:

69.0
9.1
48

Thats volts, amp hours and watt hours per mile.