I have a GR300 case with the power supply that feeds a R1225 VHF Repeater. I want to hook a 12V Marine battery to the Battery contacts on the bottom of the repeater to use for a backup battery in case of power failure; my question is this, When the power goes off here it usually stays off for a couple hours, if for some reason i cannot make it up to the repeater to recharge the battery with a battery charger, is the repeater power supply going to trickle charge it back up without harming the power supply or is it going to eventually fry due to a high amp pull? I know on some repeaters they want you to take battery off and recharge it manually when it is actually used, the trickle charge is just to keep battery charged. This repeater is a Medium to lite duty (used for fire department paging and some voice traffic).
Thanks
Mikey
GR300 case and Battery Backup Use Help!!!!
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Most power supplies' trickle chargers are a simple 20 Ohm 20 watt resistor. They are slow to charge but won't overcharge. Because of this method, the power supply won't get damaged. If you short the "battery" terminals on the power supply, you'll just heat the resistor and not hurt anything. You couldn't hurt most power supplies if you tried by doing anything with the battery.
I actually prefer to use an external relay and seperate charger.
Tessco #412177 smart charger
Tessco #463697 (don't use the charge feature- disconnect internally)
USe just a standard power supply w/o a battery option
I actually prefer to use an external relay and seperate charger.
Tessco #412177 smart charger
Tessco #463697 (don't use the charge feature- disconnect internally)
USe just a standard power supply w/o a battery option
Be sure you use a SEALED gell cell type battery. Using a "marine battery" will corrode your repeater and anything near it. Not to mention the explosion hazard.
Sealed Gell cell, are the type used in small to medium UPS units for computers ect;.
You will probally need at least the 38 amphour battery.
Sealed Gell cell, are the type used in small to medium UPS units for computers ect;.
You will probally need at least the 38 amphour battery.
I use the yellow Optimas. They are deep-cycle rated and totally sealed. They can be installed upside-down and they work fine.
One of these on a GR repeater should run for hours and hours.
I have a pair of them on a 110W Mastr II for a smaller town PD and they run the repeater and voter just fine. Change them every 4 years regardless.
One of these on a GR repeater should run for hours and hours.
I have a pair of them on a 110W Mastr II for a smaller town PD and they run the repeater and voter just fine. Change them every 4 years regardless.