Hi,
Im looking for info. Ill make it short. Why would i go for a Victron invertor and not for a Mecer invertor for a server room?
Our company is looking for a backup for the server room, and a couple of pc’s.(loadshedding) The company who is doing our IT, qoute us on a Mecer 5000va invertor. About 2kw of load.
Im suggesting a Victron multiplus 5000va + gx.(offsite monitor for batteries and invertor)
Batteries will be pylons.
The Multiplus II 3000 might be a better match and cheaper.
I’m not an expert in Axpert inverters, but if you want anything to integrate with the inverter then Victron has the upper hand by far. You can now get some data from the Axpert using the ICC software, but it is not as polished as the Victron stuff.
Also if you need a cost saving it might be much cheaper to get a Raspberry Pi3+ with a USB-MK3 cable than the full GX. Normally I suggest the GX, but if you do not add anything more (UPS mode) then the other ports that the GX supply will be wasted.
If you want to monitor things with some kind of monitoring platform (back in the day we used Nagios, I have no idea what is popular now), then the Victron world makes that a bit easier, since we have modbus-tcp support for just about anything you’d want to look at 
A question, perhaps out of ignorance, but aren’t servers typically 12VO motherboards/PSUs? Wouldn’t a battery backup make more sense? Is the inverter just there to charge the batteries from AC, or is it there for inverting battery DC to AC, just for the PSUs to make it 12V DC again?
can you monitor one of the 2 invertors on the server? and switch it off when batteries are low?
Yes you can, Check out these ATX power supplies: 1200 Watt, 48V DC Input PC ATX Power Supplies, 48 volt input (36V to 72V), now at 1200 watts, Autonomous vehicle computer power supply .
This enables you to dispense with the inverter (my pet hate!) and it will be way more efficient,
Traditionally speaking a computer power supply has at least three power rails. There is a 12V rail with a few amps of capacity (mostly for driving hard-drive motors and fans), then there is a 5V rail that has a lot of capacity (this drives the CPU and all the important stuff), and then there is usually also a -5V rail which doesn’t have much capacity. This was traditionally, because as computers evolved they became 3.3V beasts and sometimes even lower, but you still need all the old rails, so to replace a computer power supply you need something that creates all the standard levels required from the existing power supply.
Of course the existing power supply is already a switch mode jobbie, and the first thing it does is to rectify your 230VAC RMS to 325VDC (ish), and then step it down… so there is no reason you cannot start with a lower voltage (but it would have to be more than 12V I would say).
Also, years ago some data centers often had a 48VDC rail and power supplies that drove the servers directly from that. It made backup easier. Of course it was expensive… because it was not very common. I doubt that has changed much. To convert the entire thing to DC would likely cost more than the inefficiencies of the inverter plus the cost of the inverter itself…
So… no. I know that technically Richard is right every time he suggests a DC solution, but in practice it just costs too much.
How would a Victron be cheaper than a Mecer?
In initial outlay it won’t be (cheaper), of course. The argument is usually that it will outlast the cheaper inverter (and it probably will), but that is a difficult number to quantify.
I would say it really depends on what downtime is going to cost you. I’ve been out of the whole sysadmin/devops game for a bit (joke: a Devop is a sysadmin that doesn’t have his own hardware), but as I recall it is heavy on things like uptime, not sending me SMSes at 3AM that wakes up the wife (who is a light sleeper), and that can be easily monitored (so I know the power is out). I will spend extra money on that.
Interesting. For some reason I thought that servers don’t conform to the ATX standard (12, 5 and 3.3V) and therefore thought no additional hardware would be needed. I know that intel is even working on a new 12V only power standard for normal desktop platforms, with the voltage conversion circuits sitting on the motherboard. It would be quite useful if they get rid of ATX. Apparently the efficiency of the 12VO standard will be quite a bit better than ATX.
Imagine doing a warranty claim on a R500k server and they realise that you bypassed the PSU and directly connected DC to the motherboard.
I was referring to the MP II 3000 being cheaper than the MP 5000.
“About 2kW load”…Have you included all your routers, switches, servers, Internet access, door locking mechanisms, fire suppression and cooling in that 2kW - or just the servers? Sounds a bit low for a decent server room, or is it just a room with servers in it?
What type of remote control do you require, or just monitoring?
Surely you could still have some protection electronics in place?
I’ve said before, if solar inverter manufacturers could copy Online Double Conversion UPS’es tech, it would make for some seriously “safe” output currents. The ONLY change I guess that would be required, add a larger charger, to make an Online Double Conversion UPS viable.
As a matter of fact, I have a 48v 2.4kw APC on standby IF my inverter has an issue, to at least crawl along.
Personally, I would not use a Victron inverter as a UPS for sensitive equipment cause it passes what is straight through until it steps “in” to take over the loads in bad cases. Yes, PC PSU can take a lot of punches, I know.
But I can hear the Online UPS click some evenings as it takes “over” with not a peep from the Victron when Eskom does funny things in the 230v incoming.
So all sensitive stuff are running off an APC with a 12ah 24v lithium bank, to keep the power clean AND protect me against myself. 
In the land of the blind, the one eye king rule…
So, i was called into our “server backup Power” meeting. I had to sit in because i did my house inverter, so now im the “power expert” in our company. (instant upgrade)
Ive recommend the Victron MP5000, and lithium batteries. mainly because of the service, and the abuse the Victron can take. and lithiums because of the 10 year warranty. (almost a fool proof setup)
So Basically, Invertor → UPS → server room (UPS batteries are going to be replace)
The installer wanted to give us a mecer 5000va and 4x200a deep cycles.
With the server and POE camera’s on there and network switches, Nothing Major, and 10 “Till points” it should be fine (We are going to do an energy audit before anything takes place)
they also want to put on 10 laser printers. (normal HP 1320’s) if im not wrong.
That is what got me worried. I know that Laser printers draw alot of amps when it kicks on(very similar to a fridge) but my question is, how much?
Did any body measure this before?
I haven’t measured this, but I know that laser printers do need to warm up the fuser unit before and during printing which means a spike for a couple of seconds. I guess an energy audit should be able to pick it up and then it’s a case of if all will be used at the same time or not.
I remember being called out to a restaurant with a not so clear problem description from an extremely angry and frustrated owner which ended up being logged as ‘printing issues’. Turns out printing issues meant that the kitchen’s power trips whenever a print job is sent to the printer. There was a makeshift office in a corner with a small enterprise desktop printer with an extension cord going around the corner and plugging into the same plug point as the 2x deep fryers. Just having the printer switched on was OK, but the moment the fuser had to warm up before a print job it would pull enough current to trip the switch.
Why look at a RE solution over regular UPSs?
The UPS was designed for the IT industry, made to be installed in 19" racks.
So why go for a solar inverter unless you want to add PV panels?
Ink Tank printers give same page print count as lasers with much less power en ink costs. Perhaps something to investigate. (I have the Epson in tanks)
I do agree that lead acids would not be a wise choice.
Thanks Richard.
There is a UPS, and the batteries will be replaced. it was never replaced in 6 years…
The reason for the Invertor is to keep other parts of our warehouse going, like the dispatch PC’s and printers. Camera’s and WIFI. Almost all work on Laptops. So not really a BIG issue.
So the Inverter will give power to the server UPS, and then also powers the rest of the warehouse.
And YES, there was talk of putting some of the items on Solar. and to future proof a system is always wise.
We do not really have someone who manage everything. (Noby check if things are working, untill it is not) So having a system that tells you there is something wrong, is always a plus.