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KX3 Battery charging

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wn3r.us

KX3 Battery charging

I noticed that my Powerex 2400 mah batteries do not seem to be charging
in the KX3. I took them
out and put them on a dedicated charger. I'm sure they are fine.

I just installed Sanyo 1900 mah batteries to see there is a difference.
I won't know for awhile.

So here's my question: Is 2400 mah capacity too high for the KX3
charger? If not and
the 1900 mah don't charge either I will have isolated the problem. If
so, are the
1900 mah capacity OK?

All batteries are less then 2 years old and lightly used.

73, Dick, WN3R
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Matt Zilmer

Re: KX3 Battery charging

Any capacity NiMH cells are OK. They will charge at the rate of 200
mA. Your 1900's should charge from 0SOC to fully charged in about ten
hours.

Don't forget to enable the KXBC3. Try setting it to 12 hours.

73,
matt W6NIA

On Sat, 06 Apr 2013 13:01:43 -0400, you wrote:

>I noticed that my Powerex 2400 mah batteries do not seem to be charging
>in the KX3. I took them
>out and put them on a dedicated charger. I'm sure they are fine.
>
>I just installed Sanyo 1900 mah batteries to see there is a difference.
>I won't know for awhile.
>
>So here's my question: Is 2400 mah capacity too high for the KX3
>charger? If not and
>the 1900 mah don't charge either I will have isolated the problem. If
>so, are the
>1900 mah capacity OK?
>
>All batteries are less then 2 years old and lightly used.
>
>73, Dick, WN3R
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/mmfaq.htm
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>Please help support this email list: http://www.qsl.net/donate.html

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pa0pje

Re: KX3 Battery charging

And do not forget that the supplied voltage needs to be correct to
charge the cells.

I use 2400 mAh cells (Sanyo Eneloop XX) without any problem.

As stated in the KXBC3 manual:
only NiMH cells rated at 1900 mAH or greater may be charged with the KXBC3.

As far as I know the voltage applied should be more than 13.5 volts.
Using a standard lead-acid battery as a source will not work.

However I have tried to lower the voltage while charging. At 13.8 Volt
the current drawn from my power supply is 330 mA. Initially I could sink
the voltage to 12.7 Volt keeping 330 mA. Under that voltage, current
dropped gradually and at 12.0 I got the "low supply" message on the KX3
display. While charging, the voltage needed to be increased at times to
maintain the 330 mA current flow and the "low supply" message showed at
12.5 volt, which proves that you cannot get a full charge on that
voltage level.

The bottom line is: Use a power supply that can deliver at least 0.5
Amp. at 13.8 Volt as a "charge only" option.

73,
Peter - PA0PJE

Op 2013-04-06 21:22 schreef Matt Zilmer:
> Any capacity NiMH cells are OK. They will charge at the rate of 200
> mA. Your 1900's should charge from 0SOC to fully charged in about ten
> hours.
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Matt Zilmer

Re: KX3 Battery charging

Yes, 13.8VDC is required to charge. The voltage drop has to be above
a certain value to properly regulate the charge voltage and current
level.

I had a set of 1750s that I put in the KX3 and charged. They charged
faster than the nominal C/10 rate, but still charged up just fine. I
think the 1900 mAH minimum is stated so that the charge rate is C/10
or less. But lower capacity cells will also charge, just at a higher
rate.

I'm using a 9A variable switcher set to 13.9VDC output. This PSU also
powers other loads. It had to be "ferrited" half to death to kill the
switching harmonics. :)

73,
matt W6NIA

On Mon, 08 Apr 2013 16:22:35 +0200, you wrote:

>And do not forget that the supplied voltage needs to be correct to
>charge the cells.
>
>I use 2400 mAh cells (Sanyo Eneloop XX) without any problem.
>
>As stated in the KXBC3 manual:
>only NiMH cells rated at 1900 mAH or greater may be charged with the KXBC3.
>
>As far as I know the voltage applied should be more than 13.5 volts.
>Using a standard lead-acid battery as a source will not work.
>
>However I have tried to lower the voltage while charging. At 13.8 Volt
>the current drawn from my power supply is 330 mA. Initially I could sink
>the voltage to 12.7 Volt keeping 330 mA. Under that voltage, current
>dropped gradually and at 12.0 I got the "low supply" message on the KX3
>display. While charging, the voltage needed to be increased at times to
>maintain the 330 mA current flow and the "low supply" message showed at
>12.5 volt, which proves that you cannot get a full charge on that
>voltage level.
>
>The bottom line is: Use a power supply that can deliver at least 0.5
>Amp. at 13.8 Volt as a "charge only" option.
>
>
>
>73,
>Peter - PA0PJE
>
>Op 2013-04-06 21:22 schreef Matt Zilmer:
>> Any capacity NiMH cells are OK. They will charge at the rate of 200
>> mA. Your 1900's should charge from 0SOC to fully charged in about ten
>> hours.
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/mmfaq.htm
>Post: mailto:[hidden email]
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html