SRC1KUXI - Advice on what "Total battery Ah capacity connected" should be set to

[Anonymous user]

Hi all.

I recently bought an APC SRC1KUXI UPS along with 2 Nos. of 12v 26Ah SMF External Batteries.

On page 15 of the product manual, it states quote -

Function - Total battery Ah capacity connected
Factory Default - 42
User Selectable Options - 7 to 200
Description - Allows  the user to set the total Ah of the batteries connected to UPS. Battery charging current limit changes based on this setting.

EQUIPMENT DAMAGE
• Do not connect a battery string with voltage greater than 24 VDC.
• Do not exceed the maximum recommended charging current.

Do not exceed the maximum recommended battery charging current rate when configuring the battery charger current setting of the external battery system. 

The UPS is intended for use with 24 VDC nominal battery voltage. The external battery system connected to the UPS must not exceed 24 VDC nominal voltage.

-------End of Product Manual info

My unit came with a preset value of 7 for the parameter "Total battery Ah capacity connected" (factory default is supposed to be 42).

Do I need to increase this to the Factory Default of 42 (or even higher to 52 as that would be the combined Ah for both the batteries - ie 26Ah x2?).

I ask because I am facing a rather odd issue and was wondering if the current setting for the parameter"Total battery Ah capacity connected" might be causing the problem?

What's happening is that when I turn on the UPS, it shows that the batteries are Fully Charged at a 100%.

However simply using the UPS for about an hour causes the available battery capacity to drop down from a 100% to 91% - even though there has been no power outage or switch to battery by the UPS that would cause this drop. 

The load on the UPS is a mere 8%.

Could this be due to the "Total battery Ah capacity connected" being set incorrectly in the unit and if so, what should I change this value to (allowed range 7-200)?

I also cant understand WHY the UPS is losing battery charge even though there is no outage or switch to batteries at any point. 

Any advice sincerely appreciated.