Good afternoon colleagues. Can plse someone with knowledge, assist in clarifying the difference between the traditional UPS (such as those supplied by Eaton, Siemens, Schneider) vs normal Hybrid or PV inverter such as Sunsynk, Victron, etc. I have a server that I am busy with replacing the old UPS system (non-pv), which I have to make a decision to install hybrid inverters as the client has requested it to be solar connected. The load is not much, about 20-kW. Can someone send at least detailed text or references or examples. I have looked all over online I am not getting the best results. Thank you in advance.

20 kW is quite a big load? If it is 20kw than my comments below might not be valid. Our servers typically use less than 1kw per server.

In our office we converted to inverter solutions for UPS'S for our servers. A normal UPS is supposed to only provide power for a very short time while there is a power dip or when you transfer from one power source to another. The advantage of an inverter setup is that you can supply power for a long time. Our small inverter setup easily powers our most important servers for more than 4 hours. That is needed over weekends when we are not there to start the generator.

 

Many UPS's also use lead acid batteries. They have pathetic life spans when discharged deeply. So with our load shedding setup many of the batteries in UPS's only last weeks. If you put lithium ion batteries into an inverter setup they can be deeply discharged thousands of times and should last many years.

You are right. The server itself doesn't use much power. The 20-kW we were catering for cooling and emergency lighting as well. They have quite a few servers. The existing inverter uses lead acid batteries and it ten years only and it's 30kW. It was an overkill, but I assume they were planning for expansion. The current hybrid inverters (with batteries) dont have any dips or power interruption if you loose the Grid. The battery automatically takes over in fact you dont even see notice that you lost the grid. The only delay would be if the inverter itself had tripped, as it takes a few seconds to synchronise. Hence my reason to ask if ever theres still need for the traditional bulky UPS.

Just now, Justice MM said:

You are right. The server itself doesn't use much power. The 20-kW we were catering for cooling and emergency lighting as well. They have quite a few servers. The existing inverter uses lead acid batteries and it ten years only and it's 30kW. It was an overkill, but I assume they were planning for expansion. The current hybrid inverters (with batteries) dont have any dips or power interruption if you loose the Grid. The battery automatically takes over in fact you dont even see notice that you lost the grid. The only delay would be if the inverter itself had tripped, as it takes a few seconds to synchronise. Hence my reason to ask if ever theres still need for the traditional bulky UPS.

Correction: *existing UPS uses lead acid batteries........

The big difference is that inverters default to off. Any fault/error/warning and they disconnect the load (even when not on battery).

UPSs keep default to on, and only disconnect the load if everything  goes to hell.

In most cases an inverter is fine - but if you are looking for 5 9s uptime, then UPS is the best bet.

1 hour ago, Justice MM said:

Hence my reason to ask if ever theres still need for the traditional bulky UPS.

A Ups is still the best for critical equipment that you cannot afford to switch off. You could install a inverter with battery back-up upstream from the UPS as a double back-up to always keep your UPS batteries charged and will increase your back-up time during load-shedding. With a inverter back-up you could down scale  the batteries a bit on the UPS as the inverter will be the primary back-up and UPS the secondary back-up.

3 minutes ago, Gerrie said:

A Ups is still the best for critical equipment that you cannot afford to switch off. You could install a inverter with battery back-up upstream from the UPS as a double back-up to always keep your UPS batteries charged and will increase your back-up time during load-shedding. With a inverter back-up you could down scale  the batteries a bit on the UPS as the inverter will be the primary back-up and UPS the secondary back-up.

Thanks a lot