Over / under voltage protection plus time delay on my DB

Hi all

I’m looking for over and under voltage protection and a device for time delay on my single phase DB.

I came across this 12-01036 - Tripconnect 1P | Clearline Store

Anyone have experience with products from this company, are they any good or what alternatives can I look at?

Rest of the DB is Schneider components, DIN rail.

TIA

I don’t know that brand, but I have used this brand ( although not this particular unit):
They look practically identical.

Probably is the same unit…
So this is a monitor, not a surge suppressor?

It is a monitor that can switch off with a delayed restoration function.
It could switch the supply or operate a contactor.
It needs to be used together with an MCB as it also has an overcurrent function, but that will be for high-load conditions, not a fault condition.

I can understand protection against (grid) overvoltage but is this device standard for the average home system??

No it’s not standard for the average home system, but neither is Eskom and load shedding standard for the average home in the rest of the world.

I’m waiting for the sparkie to find time to install mine.

The “bad” switchover at times cannot be good, not for the system and definitely not for the stuff on critical loads. At times I hear fridge motors “rattle”. I hear the UPS’es taking “strain”. The lights dip clearly, with some of the LS events. Some you hardly even know about.

For me it has become the Standard now … want the DB away from Eskom for 5 min after LS is over.
Want the Victron to take over when the volts (subject to testing) drop past 210v or some such. We run on ±240v mostly.

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I won’t be able to answer tonight, but if @JN.V and you are seeking the same thing, I believe there is a more suitable device available.
A device which will only restore the power several minutes after it has returned, and it has to be within narrow specs for those several minutes. Isn’t that what you are looking for?
Gotta go now.

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So you already bought one as per my link?

Ja sometimes after LS I can hear my fridge motor making strange noises, same for my aircon stuttering when the power comes back on.
Just this past weekend a uncle of mine showed me, a chest freezer of his, hardly 2 years old never switches off like it used to do, the compressor runs permanently, and it’s because of this load shedding, he also lost a microwave the other day.

I got referred to the Tripconnect, the 63a one, for the main DB by @Rautenk, that same link as you posted.

From there I got three, bought in Greece, as a gift, looking near as damn the same. Rautenk and I, my sparkie, would be trying them out in our houses yes.

The Tripconnect was the original starting point though.

Think they all come from more or less the same factory.

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Guess it will be the one then, I searched far and wide, nobody else can help with something similar.

This company does this type of gear: Single Phase Automatic Voltage Switchers (AVS) - Sollatek

Bought the AVS30, and sold it again. It maxed at 30amps.

Main DB needs protection I realized, not just the critical loads.

One can DIY one too, 63a, that prices came to like R3.5k when I got prices in Dec.

Best is to install a under/over voltage relay with a contactor.
Rhomberg is good quality relays.

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I do think the sheer number of people that complain about appliances going faulty from load-shedding cannot be ignored.

I am going to make an assumption the damage to appliances happens when the power returns, not when the power goes out.

There is over-voltage, and there is under-voltage; both are possible, but they manifest damage in different ways.
Under-voltage will cause equipment like motors to overheat and burn out. Things don’t burn out in a second, though. They take a bit of time.
With an under-voltage condition, you have the liberty of time for a protective relay to take action.

Over-voltage, however, will break down the insulation and blow electronic circuits, and it will happen fast. It can be the result of a switching surge that last milliseconds or shorter. A relay that operates in 200ms is far too slow. The damage has already happened. The act of trying to measure it to switch off equipment means you’ve already taken too long to do something.

So, by all means, get Undervoltage protection, but overvoltage has to be handled differently.

For overvoltage, I would add surge arrestors (which may also be too slow anyway).
Google transil diodes they are fast enough when used in conjunction with MOVs. MOVs can still be too slow. (Metal Oxide Varistors)
However, a simple timer that delays your DB supply for a few minutes after the ESKOM supply returns should cover you. You want to wait until switching has finished and avoid that time when the whole neighbourhood is turning on its load simultaneously.

To do that a simple delay on timer will work.

Yep, I forgot to mention if your whole house supply goes through your Multiplus, then you already have a built-in delay that can be set from 60 - 600s. (PV inverters also have delayed synching).

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Not really. It takes that long before it syncs again.

I watch it. When Eskom comes back, the MP has that ±66s delay before syncing, yet it is in pass-thru mode, the power is already flowing through the inverter to the critical loads DB.

You want to stop it at the main DB, from the street.

I have not measured, but I think you are mistaken.

image

That incoming contactor (below) must open as otherwise, you’d backfeed the Grid.
It is also must be the one that is delayed or otherwise you’d backfeed the grid immediately on passthrough in contravention of NRS 097. But like I said I haven’t actually tested to prove it.

Absolutely. I can be wrong.

Working just on what I see:
LS is over, Carlo comes back on as I can see the grid draw. Full load from Eskom.
At the same time, the AC_out1 loads come back on too after the first round of relays clickety-clacking.
66s later another click, and the grid is synced.
Only then does the Eskom draw drop as the inverter starts feeding the DBs.

What you are describing:
The Carlo shows the AC draw.
The inverter AC_Out1 shows zero until the last relay syncs with the grid.

I have never seen that.