Converter 12 volt readings

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Converter 12 volt readings

Postby mustangcats » Wed Mar 30, 2016 7:14 pm

I have a question regarding the 12 volt readings I am getting at the 12 volt sockets. Normally with the trailer idle (nothing being used), the reading at the 12 volt socket will read about 13.4 volts with the trailer plugged into shore power. The last couple of days it was reading 13.0 volts when idle, so I thought I would do a test while still plugged into shore power. I turned on all the lights, I have several and they are the regular automotive type bulbs, and the reading dropped to 12.7 and stayed that way for over an hour. I turned off all the lights and it came back up to 13.0, and then I turned off the shore power and the reading went to about 12.9 with no lights on. When I turned the breaker back on to get shore power, the voltage rose to 14.2 for a couple of seconds and then settled at 13.5. With all the lights on and plugged into shore power, the voltage dropped to 13.1.

I have the WFCO 8945 and it is to have a normal output of 13.6 volts, so I thought with shore power that is about what I should always read, or was the load of all the lights too much for the converter to keep up? I don't know what the draw of all the lights would be, but there are 10 12volt automotive bulbs and 2 12v fluorescent fixtures in my trailer. Do all the readings I have mentioned above seem normal? And finally, if I'm plugged into shore power is the 12 volts only coming from the converter and not the battery?
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Re: Converter 12 volt readings

Postby pchast » Wed Mar 30, 2016 8:14 pm

sounds like all is working normally....
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Re: Converter 12 volt readings

Postby H.A. » Wed Mar 30, 2016 9:07 pm

Last edited by H.A. on Mon Apr 04, 2016 9:24 pm, edited 1 time in total.
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Re: Converter 12 volt readings

Postby Socal Tom » Wed Mar 30, 2016 10:08 pm

From here ... arging.pdf

Although a battery is called a '12 volt' battery, its voltage varies from about 12.6 volts down to
10 volts when it is discharging and can rise to 15 or 16 volts during charging. It is very
important, however, to limit the maximum battery voltage during charging otherwise the
battery will be damaged. The battery voltage should not exceed 13.8 volts for long periods
and 14.4 volts for short periods (8 hours maximum)

There is some good info on battery charging on this site, and around the net. It would be worth looking into if you aren't familiar with the concepts. Understanding the limits of battery voltage, and what "deep cycling" is, and what it does to batteries is something we should understand if we intend to run off of them for a weekend.
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Re: Converter 12 volt readings

Postby Shadow Catcher » Thu Mar 31, 2016 7:52 am

It sounds like something changed, check voltages at the battery and what is the profile of charging from the WAFCO supposed to be?
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