Lyen 12 & 18 FET Current Capability

Punx0r

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I see these have a current rating of 45A and 65A respectively. I'm guessing these are continuous battery current ratings?

Realistically, how much phase current will these take in regular use (peak and continuous) with beefed up traces and possibly the addition of the odd capacitor, if beneficial?

Are the controller cases splash resistant?

Thanks,
Ant
 
Punx0r said:
I see these have a current rating of 45A and 65A respectively. I'm guessing these are continuous battery current ratings?

Realistically, how much phase current will these take in regular use (peak and continuous) with beefed up traces and possibly the addition of the odd capacitor, if beneficial?

Are the controller cases splash resistant?

Thanks,
Ant

I cant comment for the 18fet ( but I dont think there will be any difference in current handling between the controllers ) I use 12fet with 3077's and use a phase current of around 160A for regular use but have also used 220A phase on my minimotos and they have survived and yes they are splash proof. When I setup the controller I use a 2sec rule i.e the motor needs to get upto at least half its max rpm within 2secs from a standing start and this is all down to gearing.
 
The 12 Fet outputs 45A max to the motor with the stock programming. It does not pull 45A constant on my motor, its just peak for a few seconds.

I have been going up hill full throttle and have seen 45-65 amps constant for about 5 to 10 seconds. But I have my controller set for 110 Amps peak. The motor will only allow what it can handle. The Crystalyte Motors may hold a higher constant current. MY setup in my Signature.
 
TMaster said:
The 12 Fet outputs 45A max to the motor with the stock programming. It does not pull 45A constant on my motor, its just peak for a few seconds.

I have been going up hill full throttle and have seen 45-65 amps constant for about 5 to 10 seconds. But I have my controller set for 110 Amps peak. The motor will only allow what it can handle. The Crystalyte Motors may hold a higher constant current. MY setup in my Signature.
This is because your phase current is set to low that is why you never see the set battery current.
A motor will take as much current as it can get right upto the curret limits both battery and phase which ever comes first.
 
My phase current is set for 110A, and that's what it peaks at. My rated current us set for 41A. Normal settings are 80/30. I was told you need to have a certain ratio between those two values. I don't want the Amps any higher than 110 going to the motor, thus 41 is correct for rated current. Now If I take out one of the two shunts I installed, (I have 4 total in the 12 FET) then I can set those values higher and that may make a difference holding a higher Amperage to the motor?
 
TMaster said:
My phase current is set for 110A, and that's what it peaks at. My rated current us set for 41A. Normal settings are 80/30. I was told you need to have a certain ratio between those two values. I don't want the Amps any higher than 110 going to the motor, thus 41 is correct for rated current. Now If I take out one of the two shunts I installed, (I have 4 total in the 12 FET) then I can set those values higher and that may make a difference holding a higher Amperage to the motor?
Sorry I thought the 110 was battery amps. The 2.5 ratio is a ball park figure and the actual ratio will depend on your motor and what feel you want for the acceleration. I am very supprised that you are seeing more current than your set battery current I expect that the over current protection setting is still quite high and this is why you are seeing more than the set current. I would be worried if I seen my set phase currents on the battery side as I have set phase current upto 220a on the 12fet controller .
 
I use a Watt/amp/volt meter that is in between the battery and controller and it does show pulling 110A peak from the battery. Nifty that my settings on the controller are phase 110A also. But maybe that's how its suppose to be?
 
Thanks guys. It sounds the 12FET will do the job if needed if finding space to mount the 18 FET turns out to be a hassle.
 
Punx0r said:
Thanks guys. It sounds the 12FET will do the job if needed if finding space to mount the 18 FET turns out to be a hassle.
for my middrive i will use a 9fet and go for 2kW peak. i guess it's up to the job :) if not, i'll upgrade to a 12fet. i just like the smaller form factor, and the lower Rint of the 3077 (2.8mOhm vs 3.7mOhm for the 4110) in the small 48v 9fet controller.
 
TMaster said:
I use a Watt/amp/volt meter that is in between the battery and controller and it does show pulling 110A peak from the battery. Nifty that my settings on the controller are phase 110A also. But maybe that's how its suppose to be?


Hmm, from my understanding of phase current, I'm sure someone can correct me if I'm wrong. But you should not see your phase current levels hit your battery. Phase current is applied by the controller when lower than maximum voltage is applied to the motor (hence taking off from a stop), the controller uses the additional voltages not used to upscale the current on the phase wires to the motors. At least until it reaches its desired rpm. That means you should normally never see your phase current maximum hit the batteries.

If you are seeing 110 amps hit your batteries and your current maximum rating is set to 41. Then likely you have a hal sensor and phase wire missmatch and are running with a short. You should never see more amps hit your battery than you maximum current rating of 41.

Wishes
 
Sorry, I should have specified current capability with 4110 FETS... I didn't initially appreciate the considerably difference in capability between 3077s and 4110s.
 
It does only hit 110 when taking off for a few seconds. After that it never gets that high. Even when going 20mph and pushing the throttle to full, I think the max for a few seconds is around 60-70 Amps. There is no short, the halls are correct. I have a yescom type motor GM, 9C clone and I had to swap 2 of the Halls sensor wires around to work with the Infineon controller. Runs great.

My controller has 4 shunts, not 2. That may be also why. Remember I soldered in 2 more.
 
so if you soldered 2 more shunts into the controller and the original current limit was 45A then this sort of make sense unless you reprogrammed the battery current for 45A after you soldered in the extra shunts , so 2x more shunts = 2x more current i.e 90A
 
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