I hope that Dave_A or one of the other esteemed gurus on the forum can give me some advice here. I seem to get conflicting advice from salesmen, depending on what they are trying to sell / have stock of.

Having just received our newly revised load shedding time-tables, I have decided that some backup power is going to be a must to ensure continual productivity as we are now due to be 'hit' at least 4 times a week during working hours.

As I can't use a gennie ( townhouse complex ) I have decided that the best solution would be a charger / battery / inverter option.

I'm looking at using 2 deep cycle batteries ( 94 Ah or 105 Ah, depending on supplier ) connected to a 20A charger and 1000W inverter, with household power required for essential items at a max of about 550 W. This should give me about 4 hours backup time.

My question relates to the necessity of having a UPS for my PC equipment. My understanding after initial research, is that I could have a UPS so that the UPS supplies uninterrupted power to the PCs while I go flick the manual change-over switch. I assume that the inverter is always in the 'ON' state, but does nothing until the change-over

switch is used and power starts to flow from the inverter to my equipment (?).

However, do I need the UPS if I do the following :
connect the charger to the battery to the inverter ( therefore continual top-up / maintenance charging of the battery ).
then connect the inverter to the change-over switch, to my power board ( for supplying battery power for lights, TV, etc when required )
but connect the seperate circuit that my PC equipment is on ( PCs only using about 300W - no printers ) directly to the inverter so that the PCs are always using the inverter power, thereby using the inverter instead of a UPS, and the batteries are always charged fully, and the inverter would therefore, in reality, be using the power supplied by the battery charger, and would also be isolated from fluctuations in the municipal power supply.
When the power cuts, the PCs continue using the inverter's power ( uninterrupted ) while I go flich the switch to route the inverters power to the rest of the essential appliances in the house.

Also :

1. would you recommend an automatic change over switch ? if so, can anyone tell me a make / cost / source ?

2. any recommendations ( make / cost / source ) for the best deep cycle batteries to use for this system.