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pmikep avatar image
pmikep asked

Need Clarification on AC Input Time Delay

I notice that when my batteries are at about 50% SOC and my small refrigerator comes on, the surge of the refrigerator starting will cause my battery voltage to dip, which in turn triggers my AC Input to On.

I don't want AC Input to come on unless there is is a persistent low voltage at the batteries. (Not a transient.)

So I have now set a time delay of 10 seconds on "Connect when battery voltage drops below ..."

I haven't had a chance to see what happens with this new setting. So am asking here for clarification.

Does the "Time Delay" means that the Multiplus simply waits x seconds to enable AC In after my battery voltage dips below threshold? Or does "Delay" mean that the battery voltage has to persist for x seconds - so that transients are ignored - before it AC Input is triggered On?

I expect that it is the former. If so, then a Feature Request for a Setting called "Ignore Transients" where users can set a time window to ignore voltage dip transients caused when equipment starts.

MultiPlus Quattro Inverter ChargerVictronConnect
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Alexandra avatar image Alexandra ♦ commented ·

@pmikep

Are you using virtual switch or assistant programming?

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pmikep avatar image pmikep Alexandra ♦ commented ·

Neither. I am using VictronConnect (for Windows). To talk to my Multiplus.

(Settings > AC Input Control > Delay before Connection.)

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Alexandra avatar image Alexandra ♦ pmikep commented ·

There are several time delays that can be set there, both on load and voltage.

Would you mind sharing the settings?

You may have a conflict on settings.

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pmikep avatar image pmikep Alexandra ♦ commented ·

capture039.jpg

Here

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capture039.jpg (108.8 KiB)
Alexandra avatar image Alexandra ♦ pmikep commented ·

@pmikep

Have you tried the soc and voltage combination? You mentioned it in your post as 50% where the problem is.

The delay is supposed to help with transients from my understanding i did mean to state that since it was your question.

So with soc and voltage, what you will be telling the system is to connect to sustain the voltage you set but not above a certain soc.

I was hoping to replicate your program but dont currently have a 24v system to play with at home.

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pmikep avatar image pmikep Alexandra ♦ commented ·

I am using a (cheap) Coulomb meter to read SOC. That is, it is not tied in to the Multiplus, so the Multiplus is not able to calculate SOC. So I cannot use SOC as a Setting in the Multiplus. (Even though I would like to.) I have to use Voltage.

In the meantime, I hope that you are correct and that the Time Delay is there to eliminate the effects of transient voltage dips.

I will know experimentally tomorrow morning.

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Alexandra avatar image Alexandra ♦ pmikep commented ·

@pmikep

You can use the internal battery monitor. I did for a while with my lithium's and found no problems. It can be set in the general tab.

Added a bmv as I was always reading about inaccurate readings etc on the internal one and complaints about it. But found no difference really between the two in practice.

At first we ran it separately to the system (as in no data connection) but now it is part of the system, mostly because why not.

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pmikep avatar image pmikep Alexandra ♦ commented ·

First, using the Time Delay feature worked. My Multiplus ignored the transient dip in voltage during surge start of a compressor. So that's good. My only suggestion is to rename the Feature to something like "Transient Delay Time" or have a clickable Help feature that explains it.


Second, as for using the Mulitplus's SOC feature - well, I reported about that earlier. I do not have a BVM-712. Nor do I have a BT dongle for the Multiplus. Perhaps if had both, then the Multiplus and the BVM might be able talk to each other over BT, and my Multiplus would know how much current is going to my Load and be able to show an accurate SOC during charging.

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