Uses of wet cell battery to replace the battery in APC RS900

[Anonymous user]

Has anyone ever tried using a sealed acid battery to replace the battery that is in the APC units. I have two APC's, both with bad batteries and have access to many small 12 volt sealed wet cell batteries. I would like to attempt to wire both APC's to one 12 volt battery. I have looked at the APC wiring connections and it appears that one could make a harness to supply 12 volts to multiple APC's using the charger from just one of the units. I know that I will have to station the battery outside of the backup case, but the battery is small and sealed, I also believe I can extend the harness so the battery can be remotely placed. I would appreciate and thoughts you may have on this idea. I have been a general class amateur radio operator  for over 30 years so this is not the first time I have  tried to work outside the box with both successes and failures. I enjoy the challenge and it help keeps my 72 year old mind active. If you would like give me your input?

Thanks

Casey

Ka3ebe  

[Anonymous user]

Has anyone ever tried using a sealed acid battery to replace the battery that is in the APC units. I have two APC's, both with bad batteries and have access to many small 12 volt sealed wet cell batteries. I would like to attempt to wire both APC's to one 12 volt battery. I have looked at the APC wiring connections and it appears that one could make a harness to supply 12 volts to multiple APC's using the charger from just one of the units. I know that I will have to station the battery outside of the backup case, but the battery is small and sealed, I also believe I can extend the harness so the battery can be remotely placed. I would appreciate and thoughts you may have on this idea. I have been a general class amateur radio operator  for over 30 years so this is not the first time I have  tried to work outside the box with both successes and failures. I enjoy the challenge and it help keeps my 72 year old mind active. If you would like give me your input?

Thanks

Casey

Ka3ebe  

[BillP · Accepted solution]

Hi Casey.  I, too, have used an external high capacity (both gel-cell and flooded wet cell) battery pack to power one of my APC UPS systems.  It works well and I have extended runtime as I had hoped.  The battery cables are, quite naturally, longer than if the batteries were internal so I made sure that the longer battery cables were significantly heavier gauge than if the batteries were mounted internally.

As to connecting two UPS to a single battery, I am not sure that would be a good idea because the two chargers in the separate UPS systems may protest when asked to share a single battery.  You may be able to disable one of the chargers but I don't know what potential issues that may bring.  I'd recommend a battery for each UPS.

None of this, of course, would be recommended by or supported by APC representatives and I offer my input in the spirit of keeping old minds (like mine) active.

Regards,

Joe

WB6NOO