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Current limit NS2

PostPosted: Thu Nov 19, 2015 7:35 pm
by Mpery
Hi, Ive just changed from your V3 to a NS2 regulator as I need to restrict the maximum charge voltage to 14.0v for lithium Phosphate batteries. I had the V3 set to limit the current to around 80 amps at full revs. I see that the NS2 can be limited, but must be done through a serial port interface. The output is not limited at all at the moment and will cook the 120 amp small frame alternator. What is the part number for the cable to connect to a computer?

Thanks

Re: Current limit NS2

PostPosted: Fri Nov 20, 2015 1:47 pm
by Coulomb
The serial port option for the NS2 was removed and no longer available. The manual has been updated and is available at http://www.amplepower.com/manuals/ns2/index.html.

Re: Current limit NS2

PostPosted: Sat Nov 21, 2015 2:34 pm
by Mpery
I get an "error page not found" on that address? How can I set a current limit on the NS2?

Re: Current limit NS2

PostPosted: Mon Nov 23, 2015 2:05 am
by Coulomb
There is no way to set current limiting on the NS2. Some discussion is taking place about a version with that feature, but it is only talk at this point.

Re: Current limit NS2

PostPosted: Mon Nov 23, 2015 11:32 am
by Mpery
I actually have been able to limit the current (as a percentage of rpm) by placing a 3.4Ohm wire wound ceramic power resistor in series with the field wire. The field current is reduced from around 4amps to 2amps. My 120amp small frame Bosch P type alternator is now limited to around 80amps at 3000rpm and therefore will not overheat. It still gives 60amps at 1500rpm, useful for recharging the batteries. I believe a current limiting feature should be incorporated into any smart regulator as many small marine engines make use of perfectly adequate small frame alternators which however cannot run at their rated maximum output for extended periods without overheating.

Re: Current limit NS2

PostPosted: Mon Nov 23, 2015 4:54 pm
by Coulomb
That works, but using an alternator which has to be current limited is costly, given extra engine run time required. We prefer to minimize the length of time we have to listen to noise.