Golden 36V 750 W Short in hills

[alfio]

Hi All
I have just bouth my first electric kit from Golden Motor and I´m testing it. It´s a 36 V 750 W front hub, standard controller. I use 3 x sla 12 Ah
Every time I attempeted to test the kit the same problem happens: In flat terrain the bike is OK, the cycle analyst works ok too. When I took a hill, the cycle analyst indicates even 860W power and 30 plus amp and in a few seconds starts to blink . If I try to keep the trotle in charge something melt and cut the power. It happens 3 times, two of then melt the fuse (30a) and one time melt the fuse and the plug (battery plug, IBM type)
Do you can help me?
Thanks

[biohazardman]

How steep is the hill what is the total weight of the bike and rider?  These things can have a big effect on how many amps you draw and how hot things get. Do you help by pedaling up the hill? If your speed drops much under 10MPH, for more than a short time, you may be pulling to many amps so if that is the case you need to change your riding habits and there may be nothing wrong once you fix the wiring again.   Sounds like you may need some better connectors and possibly wire and fuse though. If the connectors don't fit good and tight together then they will heat up and as amperage increases melt as you have seen.  Your controller amp limit is as far as you should go with the fuse or you can cause damage.   You can limit things with the CA so that you draw less than 30amps if I am not mistaken.   12AH batteries may not take you up a steep hill before voltage sag causes the controller to cut out.  Once you have the other stuff figured out that may pose a problem.   I have as yet not had any trouble with the stock wire or connectors on my GM even at 48V but am running a 500W motor with the 30amp fuse.  Well there are a few things for you to try hope they help.
Good luck

[alfio]

Thanks Biohazardman
The hill I said isn't very hard, but as i'm testing the kit I don't help whith pedals ... but for a 750W motor it seems too weak!! You believe the new BAC controller is better?
Other problem: The last time it burned, when I fixed the wiring, the motor don't start. I disconnect the brakes cable and it run normally. What can I do now?

[biohazardman]

I do not know about the new BAC other than it is likely not Regen from what I have read from posters. Even though it is advertised as a regen unit. By brake cable I expect you mean the brake switch wires.  If it runs with them disconnected I would guess at least one of them is causing the no run problem.  You can test them with multimeter. I think they are Normaly Open switches from what I see on the GM site. I have 2K miles on my bike and never installed the brake switches although with a recent battery upgrade I will likely instal a kill switch for safety as it often rains here and could pose a problem.
Good luck

[TOM]

Thanks Biohazardman
The hill I said isn't very hard, but as i'm testing the kit I don't help whith pedals ... but for a 750W motor it seems too weak!! You believe the new BAC controller is better?
Other problem: The last time it burned, when I fixed the wiring, the motor don't start. I disconnect the brakes cable and it run normally. What can I do now?

I think your handle brakes are broken.You could test them with multimeter.

[alfio]

I decide return to my old brake levers and ignore the switches
When I read the cycle analyst information after a fuse burn It marks a Max amp of 52,4 amp and a min Voltage of 15 V. You think this is the cause to the fuse burn? It is normal value? I know the voltage counts decrease during acelleration, but 15V seems too low! My batteries are brand new SLA (3 x 12V;12 A) and after the burns the multimeter readings still at 38 - 39V

[TOM]

Could you send your address to my email  so that I can check that.(zhourenli@goldenmotor.com)

When the current is always more than 20A,burn the fuses is normal,even burn the controller.Because the fuse can bear 15A,20A or 30A.Nearly all motors which are used for electric bicycle can't climb hill,need to help with pedal.
If your bicycle have pedelec,it could run up and down on the hill.
This kind of motor:speed and torsion are always opposite
More speed,less torsion (can't climb hill)
Less speed,more torsion (can climb hill,but very slow,can't satisfy normal need.)

[biohazardman]

52 amps is a pretty high draw for most e-bike controllers sold in kits.  A very slow speed up a hill could cause that kind of draw. Blowing fuses and melting wires would be the result if one continued at a walking pace up the hill.
 SLA batteries have a problem with voltage sag at high draw rates so the controller likely cut power at 15 volts.  Once the power is cut the battery voltage, will climb the controller will start things back up, you will once again sag in voltage, and the cycle will continue until the throttle is released.  This could blow fuses also.
 I used 12V worth of 18ah worth of SLA batts to match up to my 36V 10ah Lifepo4s for a total of 48V.  They did well together and were a good match.  No cutouts from sag with the combination of batteries mentioned.

[TOM]

Generally the controller are used for electric bicycle,the most current is less than 30A,if over 30A,it will burn the controller.
If you use 50A fuse to replace 30A,maybe it will burn your controller.But it doesn't burn motor.
But you could choose 36V 50A controller,maybe it is ok.


 
 
 
 

[alfio]

Tom
The new controller I ordered is 50 amp. I´m waiting you send it to me
How I can limit the current delivered to my actual standard controller to avoid damage and to avoid burn fuses that stop my trips to change them

[e-lmer]

Alfio;

If you run 50 Amps through the controller you risk burning the wires in the
motor unless it is rated at that current.
(Multiply the voltage times 50 to get wattage at 50 Amps.)

You should limit the current and voltage to the wattage the motor supports.

I did a quick search online and found this site:
http://www.solarseller.com/dc_circuit_breakers__dc_circuit_breaker_ul_listed_to_125_volts_dc.htm
And this one:
http://bluesea.com/category/3/10/productline/overview/14

The DC Circuit breaker is a switch instead of changing a fuse.
It is ok to have a higher voltage rating on your breaker.