TO: ALL WOOD COUNTY ARES MEMBERS (OFFICIAL)
ALL ARES AND NON-ARES AMATEURS ANYWHERE (INFORMATION)
FROM: KEN HARRIS WA8LLM ARRL DISTRICT 3 EMERGENCY COORDINATOR
WOOD COUNTY EMERGENCY COMMUNICATIONS INC.
ARES BULLETIN NR 16.09 DATE: February 28, 2016
SUBJECT: THE FLOATING SYSTEM - PART 2 OF 2
In theory of operation the power source will try to bring the voltage of the battery up to that of the power source. If the battery is not capable of reaching the voltage of the source, it will be over charged, ruining the battery, and maybe the power source. As a "general rule of thumb", the power source voltage should be adjusted to about 1/2 VOLT higher than the voltage of the floating battery or batteries. The best system uses an adjustable regulated power supply. Most power supplies are regulated at 13.8 volts, while most batteries can only reach approximately 12.5 volts. For example, if the highest voltage of the batteries you are using is 12.5 volts, the power source should be adjusted to 13.0 volts.
The advantage of using a floating battery system is that "surge current" can be higher than the surge current rating of the power supply itself. In other words, "surge current" as high as 15 to 20 amps can be produced, even though the power supply may only be capable of producing a 7 amp surge current.
Since most radio equipment today only requires about one amp of current when it's receiving, the floating system will remain at idle if set properly, and will always be there when, not if, that power failure occurs.
Ken Harris WA8LLM
WV ARES District 3 Emergency Coordinator
WCEC
Wood County WV