# Alltrax AXE 4844



## ken will (Dec 19, 2009)

http://www.alltraxinc.com/Products_ControllerPro.html


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## agniusm (Apr 30, 2012)

I have read thst but still unclear to me.


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## ken will (Dec 19, 2009)

The bottom slider controls Top Speed.


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## agniusm (Apr 30, 2012)

Perhaps I have asked wrong question. Bldc motor controllers have that 3 speed switch, is it possible to limit speed on the controller by flicking the switch?


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## ken will (Dec 19, 2009)

agniusm said:


> Perhaps I have asked wrong question. Bldc motor controllers have that 3 speed switch, is it possible to limit speed on the controller by flicking the switch?


Oh, you mean a hardware switch...no.

You could use a switch to add a resister to the throttle ...


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## agniusm (Apr 30, 2012)

Sorry for confusion. Didn't thought about resistor. Good stuff I will do just that. Thank you


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## agniusm (Apr 30, 2012)

Could someone advise on contactor? Alltrax states 250A for 400A controller and 400A for 450 axe model. I have 400A but I can only get 200A or 400A contactor. Which one to go for?


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## major (Apr 4, 2008)

agniusm said:


> Could someone advise on contactor? Alltrax states 250A for 400A controller and 400A for 450 axe model. I have 400A but I can only get 200A or 400A contactor. Which one to go for?


I see the Albright SW200 or Tyco Kilovac EV200 or LEV 200 often used and think those are well suited and maybe even overkill. It depends on your actual duty cycle (average current) of course but also the heat sink of connecting cables and ventilation of the installed location. Remember: No sense in sizing your circuit for 400A for an hour if your battery can only deliver 400A for 5 minutes  So often I tell guys to size the battery side of the controller circuit to the battery C. If you have a 100Ah battery, and plan your EV use for about an hour duration, then 100 Amperes is a reasonable figure to use when sizing cables, contactor, disconnects, etc.


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## agniusm (Apr 30, 2012)

Thanks Major. That makes a lot of sense. I was looking at the cheaper contactor like this one:
http://www.sayoon.com/en/ProductView.Asp?ID=217
Do you know if they are any good?


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## major (Apr 4, 2008)

agniusm said:


> Thanks Major. That makes a lot of sense. I was looking at the cheaper contactor like this one:
> http://www.sayoon.com/en/ProductView.Asp?ID=217
> Do you know if they are any good?


You should look for the engineering data sheet. I attached a chart from the Kilovac. Sorry I can't paste in the source but you can find it using google. The specifications will indicate what you can expect from the contactor. Offhand I'd say the one you linked might work. I have seen those types but have never used one.

By and large, the biggest problem with contactors used with motor controllers is the lack of a proper precharge. It only takes a single occurrence to weld those contacts and waste your contactor.


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