I have just installed new CCTV system at our office. I am planning to install some sort of backup system so that it won’t fail during a power outage. I think a stativolt inverter, www.staticon.ca/product-detail/stativolt-inverters is the best solution, but some people suggested that UPS will be a better option. Which one should I opt for? If inverter is the good option should I buy a pure sine wave inverter or cheaper modified sine wave inverter is good enough?