Sabvoton SVMC072150 controller review, variable regen *PICS*

The Sabvoton/Cromotor/17" Moped 23" wheel is definitely quieter than the 26" 9C on my mountain bike. If I hit the throttle hard there is some grumble with commutation, but otherwise I hear the front tire against the pavement noise till about 20, then wind. The wind noise depends on the helmet, this one I have is quieter than a bicycle helmet.
 
To put some things in perspective, I can't hear any noise over the sound of my freewheel when I'm riding without pedaling. It's by far the loudest part of my entire ebike.
 
zombiess said:
Go 18-20s if possible. The high voltage version looks like it only does 250a phase vs 350a. This is a huge difference in acceleration. With phase current controllers I'm not noticing much difference between 75-125v other than top speed.
Just got an email from Kathy.
Model SSC096150 can take 150A battery and output up to 300A to the phases. Overvolts to 120V. That sounds perfect for 24S LiPo.
 
Spec changed from what I last heard, but I'd still stay under 100v battery unless I was using a 16" moped setup and wanted +70mph. That extra 50a of phase current is not a small sacrifice. If you want silly top speed or if there is no way to reconfigure your pack, then go with 24s.

I'm probably going to get one of the 96v controllers soon myself to test since I'm placing another controller order.
 
teslanv said:
zombiess said:
Go 18-20s if possible. The high voltage version looks like it only does 250a phase vs 350a. This is a huge difference in acceleration. With phase current controllers I'm not noticing much difference between 75-125v other than top speed.
Just got an email from Kathy.
Model SSC096150 can take 150A battery and output up to 300A to the phases. Overvolts to 120V. That sounds perfect for 24S LiPo.
up to 28s :)
 
teslanv said:
Just got an email from Kathy.
Model SSC096150 can take 150A battery and output up to 300A to the phases. Overvolts to 120V. That sounds perfect for 24S LiPo.

I saw the working specs as 120A battery, 96V and 250A phase at one point. The settings in my 72V controller allow me to set the voltage to 98Vish 150A battery (I wonder if it will let me go higher on this one) and 450A phase, but I am not going any higher than 350A phase, that's asking too much from 4 parallel TO-220 MOSFETs.

I use to be a big advocate of high voltage for high speed, but that was before we had affordable sine wave based controllers. I ran 30S (125V) LiPo for a long time but I no longer see the need for it with ebikes. The main reason people went with 24S was because it let them get to 35-45mph in a 26" setup. The main reason I went to higher voltage in the past was I wanted the motor to be able to take higher currents.

I'm going to simplify this a little. The following is talking about battery current.
At 50V, the motor might only be able to take 80A of battery current from the pack, but if you up the voltage to 75V, now it can take 150A of battery current. Move up again to 100V and now it can pull 200A from the battery pack, so of course at 125A it can take even more current if allowed. How much current it can pull from the battery is determined by the phase current limit and the motor saturation. You can easily generate 300A of phase current from a 25V pack. It will have good initial acceleration but then fall off quickly.

With that said, I don't know where the limits are on something like a Cromotor. I've tried a 50, 75 and 100V pack on a 200phase amp (200A battery) controller I built. At 200A phase the only difference I noticed on my Cromotor setup in a 16" moped tire was top speed. I need to test it at 50-75-100V and +300A phase current and I have not had the chance to do so yet.

I'll try to test out 100V and probably 125V once I get a controller capable of higher phase amps (aka finish building my 18 FET TO-247 controller that's been sitting on my bench for too long). I've been spending the last few months of free time studying theory and learning DSP programming for some controller/inverter projects I'm working on with someone else who is counting on me to do my part.

One argument I would make for 24S on a controller like this is if one is using a slow wind motor or using a small tire diameter <22". I'd toss this controller on my suicide bike at 125V and do an 80mph video if they sketchy bike didn't fall apart (feels so so at 60mph, definitely not "safe" or "confidence inspiring). Thing is once I did the video I'd probably never go that fast again.

I strongly believe it's more effective to drop to 85V max for most "ebike" use, 24S isn't needed like it use to be.

I'm old now :( Still a hot rodder at heart, but I've got been there done that syndrome. My daily driver is 3100lbs, 750HP and it doesn't feel fast any more. Even my 3640lb 900HP car stopped feeling fast. When I let people test out my ebikes most of them are freaked out by the power and I have them turned down to 7-10kw, not the 15-18kw I sometimes use (for fun and testing).

BTW, you don't want to see a KFF with a 125V pack. A 200A fuse going off on a 125V pack is about as loud as a 9mm hand gun and literally explodes. At +100v you don't even want to touch the leads, it can easily be lethal. We often toss around the idea of running a 100V pack like it's nothing. It can be done, but you must be safety conscious and know what you are doing. There are a lot of noobs just starting off and they are trying to dive into 100V setups with no electrical experience. I'll sell a product if there is a demand for it, but I want people to understand the safety and risks they are taking.

When I started selling high power parts it was to mostly technical experienced people pushing the limits. Now I'm selling to guys fairly new to this hobby so I feel some responsibility to try and educate as well. Caveat Emptor.
 
zombiess said:
BTW, you don't want to see a KFF with a 125V pack. A 200A fuse going off on a 125V pack is about as loud as a 9mm hand gun and literally explodes. At +100v you don't even want to touch the leads, it can easily be lethal. We often toss around the idea of running a 100V pack like it's nothing. It can be done, but you must be safety conscious and know what you are doing. There are a lot of noobs just starting off and they are trying to dive into 100V setups with no electrical experience. I'll sell a product if there is a demand for it, but I want people to understand the safety and risks they are taking.
This is more of a problem that if you use a fuse, where it is generally chosen to match the maximum current, taken by the controller, you don't want to risk stressing the fuse and eventually blowing it, or causing an overcurrent, when riding.
If a circuit breaker is used it could be at a much lower current value, determined by the breaker current overload curve.
So instead of 200A fuse, it could be say 50A breaker, this means the protection is better in the case of a short circuit and there is little or no KFF, when dealing with ebikes sized battery packs.
I shorted out a 125V/ 8Ah pack with a 40A breaker, in line, there was the small gun shot, but because the trip happens in around 2mS, there was the teeniest damage to the shorted wire ends,

zombiess said:
When I started selling high power parts it was to mostly technical experienced people pushing the limits. Now I'm selling to guys fairly new to this hobby so I feel some responsibility to try and educate as well. Caveat Emptor.
Get where your coming from, the short circuit current from most ebike packs would be good for welding, though the effects of high currents doing damage would be more prevalent than a kick from 100V dc, if you have cuts on your hands or wet you could get a good tingle or even a kick, but electrocution would not be the risk as opposed to getting flash burnt, some guys use like A123 cells with mOhm resistance and then parallel them up for 48V/2P for range and that could deliver the same current into a dead short as 96V 1P.
 
What type of circuit breaker? Does it have to be a marine style DC breaker, or could I grab an AC panel breaker from Home Depot for $10?
 
teslanv said:
What type of circuit breaker? Does it have to be a marine style DC breaker, or could I grab an AC panel breaker from Home Depot for $10?
You would want to keep it dry, as all your bike electrics should be, eg in your battery box, it is also excellent as your battery isolator, so being readily accessible would be good to isolate the pack ( remember your pre charge though).
Because a c. breakers aren't designed for d.c. use they have to be voltage derated, you might find in their data sheet a d.c. value anywhere up to around 48- 70V d.c. generally, check the data sheet.
Warning, if underrated, you could smoke them and they might not let go of the arc, giving you a spectacular melt down if it's a cheap thermoplastic.
The other way is to buy a solar d.c. breaker of eBay for cheap, these are nominally range from 125 - 200V dc and polarized (+/-)
Examples https://www.asi-ez.com/member/~NDB2Z-63C50-1.asp? http://all4solar.com.au/SHOP/index.php?main_page=product_info&cPath=7&products_id=146&zenid=7ri62ininhg4f4qcsqls19j3d6
Can be as low as sub $10 if you shop around.
Curves are usually B/C.2014-11-12-08-30-14--2080177176.jpeg
So depending on your current draw and your data sheet curve, you could pull 2x for around 1 minute, 3x for 5-10 secs.
Eg 50A breaker, that would be around 63A for over an hour (they don't trip at rating) 100A for around1 min or 200A for several secs.
So a nominal 80V@63A, over 5kW continuously.
 
Alan B said:
I picked up a pair of the 63A solar breakers, was thinking about running two in parallel for 120A or thereabouts, any problems with doing that? Running 18S 72V nom.

Sorry Jeremy, the mods may want to shift breakers questions to another thread.

There a problem, with current share due to small differences in breaker resistance and tolerance, even if you have a double pole (mechanically connected breaker) the difference will mean one breaker is taking more current, though it would still work, but you possibly have to current derate the 2x value, I've got a few double poles, I'll give it a try and let you know.
Remember though your 63A is rated to trip at around 1.33xI or a 80A for 1 hr or more, 6.4kW @ 80V, or 126A for a minute or more is that enough?
Another option, which would not help current share any, but could be easier for wiring, for paralleled setups is to run say a 2P through as 1+1P.
 
I'm running the Sabvoton from zombiess, so this is somewhat relevant to the current topic, unless zombiess disagrees.

One breaker will probably handle enough current, I may want to try the full 150/300A but the high currents would not last long, so one would probably not trip.

I wonder if the breaker trips at full current if the back EMF will be properly controlled, or if damage might result to anything.

I'm aware that the current won't split perfectly, though with my dual #12 pack wiring there would be a small resistive divider in the wiring that would tend to even out the current. Even if not perfectly 2x the single breaker rating it would be much more than a single breaker. But I'd rather use just one if that is going to work well.

There is a 200A fuse there now, quite a mess if that blows. Plus the convenience of turning power off would be nice, I plan to put a precharge momentary pushbutton around the breaker so it doesn't have to charge the caps. That switch use of the breaker would not be thrown often, just for winter storage or working on the electrical system.

Anyway it would be nice if a single Solar 63A breaker would be a good match for this setup, or a pair of them for the folks pushing the limit. They are rated for good DC voltage and not expensive. They are also a lot smaller than contactors or battery disconnects.

Thanks for your comments.
 
guys AC breakers don't work well for DC.
 
Alan B said:
I wonder if the breaker trips at full current if the back EMF will be properly controlled, or if damage might result to anything.
In brushed motors, at least, disconnection of battery from controller can be disastrous, because the collapsing fields of the motor can backlash very high voltage spikes inot the controller. There is a page on the 4QD controller pages about some incidents involving that sort of thing caused by loose connections to the battery, and some of the damage was pretty catastrophic, starting with FETs. I can't find the link right now.

I don't know for sure, but I expect the same thing could happen with brushless, because if there's nothign to absorb the current back in (battery) tehn any generated voltage spikes above the FETs or caps capability to absorb them doesn't have anywhere else to go, and if high enough to exceed ratings, could do damage.



That said, I can't recall of the top of my head any threads where a blown fuse or popped breaker under load resulted in a dead controller, so unless the conditiosn are right, it is probably ok.

If you wanna be sure, you could always install some voltage spike protection that is very fast-reacting, and starts below the max FET/cap voltage--It would go on the controller side of the breaker.
 
Alan B said:
I'm aware that the current won't split perfectly, though with my dual #12 pack wiring there would be a small resistive divider in the wiring that would tend to even out the current. Even if not perfectly 2x the single breaker rating it would be much more than a single breaker. But I'd rather use just one if that is going to work well.
Yeh, probably find 1x 63A will do your job for about 10kW, for a minute or two, ( leave a bit of a window, for hot conditions) but double pole, which are even more common to get and still cheap, you've covered your ass, even with crappy power sharing, it'll still easy do your 150A battery.

One thing i would suggest, though it not be recommended with a pack anyway, is subject to too hard a mechanical shock, as you might get an inadvertent trip, though the bike I presently have has no rear suspension and the breaker lives in battery box, which is surrounded by 10mm foam inside and no trips at all.

Alan B said:
I plan to put a precharge momentary pushbutton around the breaker so it doesn't have to charge the caps. That switch use of the breaker would not be thrown often, just for winter storage or working on the electrical system.
Yeh that's good, my setup has an auxiliary 1/2 din switch linked to the breaker, which won't let the breaker latch, without it and that is connected to the precharge circuit, so I can isolate the battery after every ride and not worry about switch on precharge, which makes it all the more safer and the battery charger connections are before the breaker too.

Alan B said:
Anyway it would be nice if a single Solar 63A breaker would be a good match for this setup, or a pair of them for the folks pushing the limit. They are rated for good DC voltage and not expensive. They are also a lot smaller than contactors or battery disconnects.
Thanks for your comments.
No worries, its usually fairly simple to split a double pole too, if need be for space/spares/ 2 bikes,
Hope it goes well mate, good luck with it.
 
amberwolf said:
Alan B said:
I wonder if the breaker trips at full current if the back EMF will be properly controlled, or if damage might result to anything.
In brushed motors, at least, disconnection of battery from controller can be disastrous, because the collapsing fields of the motor can backlash very high voltage spikes inot the controller. There is a page on the 4QD controller pages about some incidents involving that sort of thing caused by loose connections to the battery, and some of the damage was pretty catastrophic, starting with FETs. I can't find the link right now.

I don't know for sure, but I expect the same thing could happen with brushless, because if there's nothign to absorb the current back in (battery) tehn any generated voltage spikes above the FETs or caps capability to absorb them doesn't have anywhere else to go, and if high enough to exceed ratings, could do damage.



That said, I can't recall of the top of my head any threads where a blown fuse or popped breaker under load resulted in a dead controller, so unless the conditiosn are right, it is probably ok.

If you wanna be sure, you could always install some voltage spike protection that is very fast-reacting, and starts below the max FET/cap voltage--It would go on the controller side of the breaker.

I fitted a 150A reverse diode across the breaker on my smaller scooter, this was to allow regen currents to feed back into the battery if it tripped , it seemed to help as the 18FET infinion I used usually blew under regen braking.
 
Tried the current share, with two breakers cabled in parallel, with a loop of wire either side, passing a very large, initial charging current, there was approx' 1A difference, at around 64A & 65A, so current share no issue, as long as terminals are good and tight.
The lowest short circuit handling current of the cheapest breakers are about a minimum of a standard 3kA, so individual tripping of one under a short circuit, should'nt normally be a prob', unless you want 10P :mrgreen:
 
Hey Jeremy, just a bump to see if you ordered a 96V for appraisal, as I'm definitely want two, fits better with my 200V+ charging scheme.
Cheers
 
Variable Regen Testing

I wired up a thumb throttle to test the variable regen. A standard ebrake lever is used to generate the contact closure to enable the ebrake, and the thumb throttle to generate a 1-4V signal for the controller. My setup is a Cromotor with 17" moped wheels in a Greyborg frame and this Sabvoton controller from zombiess.

Initially I set it the regen value to 50 and the slip regen to 30. This made the throttle off coasting regen a bit strong, but that was all I had before the thumb throttle variable regen control was added. I set slip regen down to 20 after setting up the thumb ebrake control, and that is a more comfortable coasting deceleration.

When I added the variable regen control set to 50 it didn't seem to do anything, it was so weak, even with the thumb throttle fully depressed. I turned it up to 100 and it felt useful but still weak. I corresponded with zombiess and he suggested 500, so I tried that. On my bike 500 was too much, causing difficult to modulate braking and rear wheel skidding. The motor turned somewhat backwards during hard braking, making the pedals push into my feet. It was impressive braking but I wanted more control. So I tried 300, 250, 200. At each step the skidding reduced and the control improved. At 200 it stopped skidding, so I tried 220, and it still did not skid on dry pavement, but it produced very hard braking while allowing good modulation through the range. So I left it at 220 and will be riding with that setting as weather permits, a big storm is headed this way tonite so I may not get much riding in for a week or so. I may decide to increase it so it will just produce skidding, right now it barely doesn't, at least on the old clean dry pavement of the local street.

I'm not too thrilled with the ergonomics of the thumb throttle brake setup, but the variable feature on the Sabvoton is excellent. I would like a brake lever that generates both the contact closure and the 0-5V signal. I'm working on something for that, but in the meantime the thumb throttle will be used.
 
Zombiess,

Have you tried one of these controllers on your 2 turn Cromotor? I'm wondering if these or sine wave controllers in general handle low inductance motors better than the old common controllers, since they have better control over phase currents.
 
Can someone confirm the dimensions for this controller ?

243x146x62mm - Are these correct ?

Pretty sure I am going to use this controller on my phasor , but one concern I have is if it's 146mm wide and my frame is 100mm wide
and with the fins off to the side need to see how I can mount it. Thanks
 
ohzee, the fins are no more than 10-12mm wide on each side, so there is NO WAY you can make it 100mm wide. period.
if you want me to measure any specific part of my 072080 controller, PM me.
 
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