Continue ac input 15 minute delay

We have a requirement in an estate to delay connection of AC input for 15 minutes after power returns.

AC input control load based delay is maximum 254s.

How else?

This is cheap and won’t satisfy your needs:

Of course there will be things like Ziehls and the like that will probably do it.
I suspect that if you did a bit of searching you’ll find something far more inexpensive with a settable timer.

Edit: Of course you could always cobble together something like this together with an external timer and a contactor.
Edit: You haven’t specified a the current (1ph or 3ph) that must be switched? If it more than 100A, then you probably won’t find an inline device.
Here is one 10 mins adjustable: (Two in series?)
image

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@warwickchapman You did not specify what equipment you already have and it will influence my comment below.

We have a similar requirement born out of a huge spike in load as all the batteries start to charge at the same time from grid. This obviously happens at night and only if your SOC dropped below the Active SOC limit EG. you set 50% and with Load Shedding it dropped to 20% Correct me if I am wrong but the grid will charge the battery back to 50%

Anyways, the three options are as follows and listed according to cost.

#1 Use an Assistant to drop the charge current down to 1A. This way you get back on the grid but charge at only 1A for the first 15 minutes. There is a caveat that I couldn’t get the Timer function to work properly but I haven’t spent too much time on this. This would be my choice.

#2 Put that additional timer and contactor in your DB like @Phil.g00 suggests. This unfortunately will delay your charging by 15 minutes and if your supplier decides 15 minutes is not enough and they start to extend this then you will have to carry the cost if your battery is so closely spec’d to EG. Load Shedding schedules, and you run the risk of battery shut down if you now have a longer than anticipated outage.

#3 At the considerable cost of a Zhiel which could do the same as #2. If you have a Quattro then you probably have a Zhiel already and you made the upfront capital outlay in the beginning.

My bad. Victron Quattro and GX device et al

My reference to AC input control was to the new features:

Where it says 60s there upper limit is 254s.

Ah, I missed that. I haven’t used that GUI interface at all. My reference was purely from a VEConfig perspective.

Is there a real world reason for that restriction? Seems strange that the limit is 254 (one less than 255)… maybe it is a limit on the input field’s variable type?

Oh it is very likely that an unsigned 8-bit integer is tasked with the job, which means the maximum you can have is 255 (or 0xFF in hex, 11111111 in binary). But quite often the top number (0xFF) is used to indicate something else (value not set, value not supported, etc), so it is very common (also for other manufacturers) to reserve 255 for something, leaving 0-254 as usable values.

Also, the default state of many non-volatile types of RAM (flash, NAND, etc) is all ones. So a value of 0xFF is a good choice for “unset” or “invalid” because quite often that is exactly what it is!

So maybe you can give the input another 8 bits? :sweat_smile:

Indeed. You can switch from 8 bits to 16-bits. You would then have a range from 0-65534, again reserving 65535 (0xFFFF) for another purpose. This should be enough for 18 hours of waiting…

But you need to convince the guy who made the firmware of the inverter. Because like Gates of old, he probably said “a few minutes should be enough for anyone!” and called it a day.

What is interesting is, how do they (The estate) get away with being non-compliant with the Grid Code?
Also NRS097 requires that inverters reconnected in no less than 60seconds but not more than 10minutes!

So that would be an interesting argument. I do understand the spike issue, but this can be managed by assigning a random time to each house (in the 10 minute period)…

Just saying…

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Well there you go @warwickchapman, looks like you need to convince someone to save a “byte” for you and send some new firmware. :sweat_smile:

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Usually estate only wants to delay battery charging to prevent all battery charging kicking in when grid returns and exceeding max demand limit on estate bulk connection. In past we have implemented with contactor on inverter input controlled by delay timer relay.

Conjures images of a Dennis Ritchie sage type…

Ya, I’ll bring it up on Victron community and let’s see.

I eventually settled on an option #1.5. The Victron Timer is not working for me, neither for ACOut2 relay control nor the Charge Control assistant.

I went and bought a cheapie timer, connected it to my Zielh (same output that controls my Contactor) so as soon as the contactor energizes and reconnect my inverter, the timer starts counting for 10 minutes. After 10 minutes it opens the contacts.

Programming is a Charge Control Assistant on AUX1. My relay contacts connect to AUX1 and when closed charges at 1A only and when open then all hell breaks loose and Eskom phones to say I should stop charging from the grid. Done. It Works!

The nice thing is that it only affects grid charging, during the day my RS450 charges my Quattro as hard as the winter sun bakes down on the panels.