Hi

I have run the invertor so far in USB or SUB modes. Yesterday I decided to try SBU mode and it works well, except that I became hearing some clicks inside inverter. Like some relay switches. It happens in random intervals,  somtimes once per a few minutes, sometilime a few times per a minute. No matter is it day or night. I made a guess that it maybe dry contact relay, but I checked with a tester and it looks stay in single state.

So I just curious what is a source of that clicks. Any ideas?

Thanks

Ps. I found just a couple of similar complains on another forum. Without referring to a mode and without an answer. And i haven't use connection to pylin bms.

https://forums.aeva.asn.au/viewtopic.php?p=95978&sid=8ece6d65173bd301456b956c8d11959f#p95978

Maybe someone has an electrical scheme of King or knows purpose of 4 relays on the main board (visible on pictures in the service manual)?

On 2024/04/17 at 4:36 AM, Vitaliy said:

Maybe someone has .... or knows purpose of 4 relays on the main board...

All Axperts have these three relays:

* AC-in "safety" relays (switches AC-in Line and Neutral) to load and possibly DC-AC converter

* Load relay (disconnects AC-out from everything else)

* Older models had a fourth relay, at the output of the DC-AC converter. Later models don't bother the the DC-AC converter live connects to the junction of the other two live relays.

* It's possible that the Kings have a fourth relay associated with the PFC stage (the AC-DC converter/rectifier). [ Edit: This is confirmed by the block diagram in the King service manual; see a few posts down. ] It's also possible that the King's service manual is inaccurate or out of date.

There is also a relay at the output of the solar charger (MPPT) in 145 V max PV models, including the King 1 but not the King II. This is actually two relays in parallel to make the current rating. To me, these relays make more of a long"tiiiing" sound than a click, but it possibly depends on what particular brand of relay is used.

My wild guess is that it's the MPPT relay that is making the sound, and that you have older firmware. Anything older than 72.00 (71.xx) had issues with solar charging, and 72.00 still has a few. I have no experience personally using firmware version 72.04.

Edited April 19, 20242 yr by Coulomb

Thank you, mate!

I returned to SUB mode and clicking disappeared.
I don't think it's any MPPT relay clicking because what is the difference for MPPT how to work in SUB and SBU modes?

It's obviously not the Load relay. )

I saw a few schemas that I found in https://powerforum.co.za/topic/14666-repair-of-axpert-inverters-a-journey-started/.

One is Mixo's schema


Second is


I have no idea which relay except "Earth bound" can continuously  (RY1?) clicking in that way I don't see any side affects on the load side.

And if it this relay clicking - what is the reason to do this? Bug in firmware?

Also maybe it periodically connect\disconnect AC charger (input part of dual transformation in AC IN->battery + MPPT-> AC OUT).
But again - why??

I have no idea how old is board version in my inverter. I bought it in Jan 2022 and it had 72.00 firmware from the factory.

Thanks

 

Edited April 18, 20242 yr by Vitaliy

Ah, thanks. From that block diagram, the extra relay that Kings have would be the one at the input to the Power Factor Correction stage (rectifier, AC-DC converter). I suppose that might click on and off if the power levels happened to be such that only a little assistance is needed from the grid, and as loads and available PV change, the need for grid assistance comes and goes. 

Hmm. It's possible. I'm sure the inverter has AC voltage sensor before this relay (because there is no gaps in his values history)
But indeed, maybe somewhy the inverter periodically connects AC charger.
Btw, I have wifi power monitor just before AC input of the inverter and in days when I used SBU mode it didn't show more then 1W consumption.

Mostly zero.

But I can make an experiment - again switch to SBU mode and then disconnect input of inverter from power meter (I have the switch between). And then ensure that 1W isn't own consumption of the meter.

Btw, in SUB or USB modes if the grid disappeared -  nothing clicks inside the inverter


This clicking makes me a bit mad, especially not only due noise, but also when I thinking that it makes unnecessary wearout of the relay contacts and potentially can relatively quickly  kills the relay

Edited April 20, 20242 yr by Vitaliy