Multiplus-II x3 5k query

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Transfer time query. According to above from manual my understanding transfer suppose to be 0ms or very close to it, my issue is that when loadshedding kicks in my computers/screens switch off/ freezers compressor start making noise and have to be restarted computers. Subsequently UPS installed inline on some computers, not all

Is there a setting or config i am missing?

It is about a 20mS changeover.

The trick is, can the devices take that 20mS break?
PCs should, the capacitors in their PSU are big enough.
Some AC to DC PSU may not.

It all depends on the size, age, and the size of the capacitor inside a PSU.

Me, I always install 2nd hand free UPS’es (I replace their batts with Lifepo4 cells) before sensitive electronics.

Why? The power from the street passes straight through all solar inverters.
Basically for additional protection against Eskom woes from the street.
With LS it then also mitigates the changeover, as a byproduct.

As TTT has said, the changeover is about 20ms. Compared to a decent UPS, this is not particularly great. But it’s not bad either.

When running ESS, there may be a significant voltage dip during the changeover, as the grid falls out and for a split second, while the inverter tries to power the entire grid in reverse, before the transfer switch opens. This brown-out probably causes more issues for people than the 20ms transfer time (when used as a pure UPS).

But still, most appliances should be able to handle the dip. If a computer cannot handle it, it usually means looking at a replacement PSU, as the one you have no probably has dried-out caps.

I bought a brand new Gamdias 600w PSU for my sons pc and it switches off when loadshedding starts.
Funny enough the other sons has an old 750w and his pc stays on

Yeah, I read of others having done the same here, and on other forums.

The ONLY 100% sure solution is a small UP just to carry the changeover … in my opinion.

You can pick them up for “free” … ask your kids to ask on their social media for anyone who wants to throw away a UPS. :slight_smile:

Then just replace the batt with the cheapest 12v 7ah batt you can find. It hardly ever works, so it should last long.

Check if the PC also turns off when you trip the power manually, vs when the grid fails (which is much harder on the inverter). If it survives a manual power trip… then a solution that disconnects from the grid before the power fails may be the solution. There are ways to do that… but they are somewhat technical.

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I now have a few extra hours of “LS” … when the Tripconnect disconnects the house from the grid when the volts go over 250v. It is a “thing”.

Does make LS a little bit “easier” to handle for the inverter though, as Plonkster says, it disconnects the house near instant from the grid when LS hits, and takes an additional 5 minutes before it re-connects when LS is over, that irksome time when transformers take severe strain.

Transformer is the least of it. The transfer switch essentially operates on a dead short.

I know and when the voltage is too low as well

@plonkster
Technically how would i be able to disconnect from the grid before LS? coz the LS schedule is never the schedule

& thanks to both the true blue OG’s :wink: for explaining

If you want, install one of these the first thing in the main DB.

There are ways it can be done with Node Red. But it requires a lot of technical know-how, and it requires the load shedding schedules to be at least somewhat correct, by which I mean it is okay if it is off by a few minutes (up to 20), as long as load shedding never starts early or the schedule is not adhered to.

Then you can use an automation method (such as node red) to flip the inverter’s “mode” (switch position) from “On” to “Inverter only”, which will drop the grid early.

Newer PSU’s support PFC. They can be very iffy to changes in power.

@TheTerribleTriplet Would you mind sharing your settings for your tripconnect?

Our average volts are ±242v.

Tripconect:
Cuts off at >250v and below 215v.
Stays off for the max time after LS returns, I think 5min.

Why 250v, Victron takes over in any case at wot, 253v(?). Hearing the bedroom fan running at 252.9v, yeah, no.

Then the 2nd penny dropped for me when the fan dropped down to 230v when Victron disconnected the critical loads from the main DB. It dawned on me: Now hold on, what about the non-Critical loads still connected at 253v (or higher)?

Below 215v to not go down to wot, 195.5v(?), as low as the inverter will go “braking” all the way. Why thought I, LS is here, let’s not “argue” shall we? Just “let it goooooo”. :slight_smile: