Axpert invertors

[Gnome]

constant power? Please explain. It works similar to the Axperts, but where the Axpert is not a true hybrid, the infini is. The infini can also grid-tie.

I mean grid-tie typically turn off when mains power fails. Is this not the case with the infini?

What I meant was if axpert have a visible led when on inverter you can use optic sensor to activate earth bond on output

Opto-coupler (very low level one), could work well and reliable (not bad idea). Still waiting for my Axpert to arrive, can't comment on other options yet

 

[thehuman]

I mean grid-tie typically turn off when mains power fails. Is this not the case with the infini?

The way I understand the infini
Takes batteries
Have load ac output
Have mains ac input
But it can send exess solar energy back into grid via input
When mains fails it isolates input and runs loads via output

 

[superdiy]

I mean grid-tie typically turn off when mains power fails. Is this not the case with the infini?

No, the infini has separate mains input and output connections, where normal GTIs only have a single mains connection. Normal GTIs switches off when the mains fail and no power is supplied to the inverter load, but with the infini, if mains fail the infini still supplies the load with power.

Opto-coupler (very low level one), could work well and reliable (not bad idea). Still waiting for my Axpert to arrive, can't comment on other options yet

Not really a simple solution - the same LED is used for Mains on and inverter on:
Solid On - Output is available in bypass mode
Flashing - Output is powered by battery in inverter mode

 

[scottwday]

The first LED flashes in inverter mode, it'd be possible to do an optical pickup but kindof dodgy for something that's supposed to stop you from getting electrocuted.

The COM port lets you poll for the inverter mode, and there's power available on the port. I've got arduino-ish code working that can get the messages from the inverter, just not finding the time to get everything finished. If anyone's familiar with that sort of thing the code's on my github, I'm updating it as I go.

 

[superdiy]

The way I understand the infini
Takes batteries
Have load ac output
Have mains ac input
But it can send exess solar energy back into grid via input
When mains fails it isolates input and runs loads via output

Yep, in short. It also has a lot of priority settings, similar to setting 1 on the Axpert. It will combine PV and battery (when eskom is off) to supply the load and it will honor the priority setting - either battery first or PV first. It will also combine eskom and PV to supply the load (when eskom is on) and it will honor that priority setting - either PV first or utility (eskom) first.

 

[superdiy]

The COM port lets you poll for the inverter mode, and there's power available on the port. I've got arduino-ish code working that can get the messages from the inverter, just not finding the time to get everything finished. If anyone's familiar with that sort of thing the code's on my github, I'm updating it as I go.

That sound's more like a "real" solution. We can design a "dongle" with an on-board relay, which you can plug into the serial port, without any warranty issues.

 

[scottwday]

That sound's more like a "real" solution. We can design a "dongle" with an on-board relay, which you can plug into the serial port, without any warranty issues.

That's the idea, but unfortunately I don't think the axpert and infini units use the same interface. The inifni uses modbus AFAIK, the axpert uses its own weird protocol.

 

[superdiy]

That's the idea, but unfortunately I don't think the axpert and infini units use the same interface. The inifni uses modbus AFAIK, the axpert uses its own weird protocol.

That's not an issue, we can make one for the Axpert and another for the infini. But wait, that is the same connection where you would connect a PC to and if you use the port for PC connection, you cannot connect the dongle and the E-N bond will not work.

 

[superdiy]

Up until now, the explanation and drawing in this thread is the only workable solution.

 

[Gnome]

That sound's more like a "real" solution. We can design a "dongle" with an on-board relay, which you can plug into the serial port, without any warranty issues.

The reasons I don't like that solution:

1) You use the com port
2) You are tied to your poll rate
3) It relies on a fairly complicated piece of technology in comparison to a simple little relay

 

[scottwday]

That's not an issue, we can make one for the Axpert and another for the infini. But wait, that is the same connection where you would connect a PC to and if you use the port for PC connection, you cannot connect the dongle and the E-N bond will not work.

I don't want to announce something I might not get finished, but the 'dongle' has wifi which uploads status to a logging service. I haven't implemented downloading or writing any settings on the inverter yet, but it'd be possible. So I don't see much need for a PC connection.

Also there's no reason why the dongle couldn't have another RJ45 port to pass PC commands through

 

[superdiy]

The reasons I don't like that solution:

1) You use the com port
2) You are tied to your poll rate
3) It relies on a fairly complicated piece of technology in comparison to a simple little relay

Just keep in mind that the simple little relay option would only work in UPS configurations without any PV panels connected to the Axpert.

 

[Getafixx]

By "We were working on a solution here", do you refer to this thread? I'm still stuck because I have an infini, which is a true hybrid, and I have PV panels installed as well. The infini combines PV power and Eskom to supply the load, no simple relay which switches between PV and Eskom to which I can connect a "bonding" relay.

I thought the infini does not have the floating neutral problem? Maybe I remember incorrectly.

 

[superdiy]

I thought the infini does not have the floating neutral problem? Maybe I remember incorrectly.

That would be great news, I'll have to check it out. I still need a solution for the Axpert installation though.

 

[Gnome]

Just keep in mind that the simple little relay option would only work in UPS configurations without any PV panels connected to the Axpert.

No arguments there

Both have pros and cons. I was just stating the cons (the pro being it works for all configurations).

The relay cons are:
- Only works for UPS mode
- Fails silently (true for both options so far actually)
- May result in Neutral/Earth not being connected if the inverter is not using Utility while utility is available (this is a real possibility but should be rare)

Cases where you may be running on Inverter when Utility is available:
- Frequency out of range
- Voltage out of range
- Transfer from battery to utility is delayed

So don't get me wrong, there is no silver bullet here.

In my opinion the only *real* silver bullet is relay connected to the Inverter internal UPS relay and have that also turn on your ground relay.

 

[greg_SA]

Just keep in mind that the simple little relay option would only work in UPS configurations without any PV panels connected to the Axpert.

Yep - that was confirmed earlier in the thread.

I'm pretty sure many (if not most) inverter / UPS installations have some serious flaws. If an installer uses a generic SANS diagram, and doesn't understand the detailed working of the specific inverter/UPS, then there is bound to be an issue.

 

[thehuman]

What if you don't conect axpert output earth to your ups db
But instead create a new separate earth by taping of the output neutral
A isolated earth cable to devises will be advised
Earth leakage on output should be working here
Feel free to shoot it down if unsafe

 

[Dimpie (JIGSAW)]

I thought the infini does not have the floating neutral problem? Maybe I remember incorrectly.

I also remember this & I'm sure it was mentioned in this thread that the Infini have the auto-switch/auto-bond built-in

EDIT: RCT-INFINISOLAR 3K PLUS & 10K is now also awailable through Rectron

 

[Getafixx]

What if you don't conect axpert output earth to your ups db
But instead create a new separate earth by taping of the output neutral
A isolated earth cable to devises will be advised
Earth leakage on output should be working here
Feel free to shoot it down if unsafe

I can't think why not as long as your separate earth has its own ground spike. But I cannot comment on whether it is legal or not according to SANS

 

[Getafixx]

A while ago I had another idea which is unfortunately flawed, but maybe it sparks something else.

I thought of bonding the input and output neutral. Since the output floats I am pretty sure you can bond the output neutral to the input and it also takes care of the grounding problem both on batteries and on Eskom. Current won't flow in the 'house' neutral when running off batteries because that is not part of the closed electrical circuit. The only problem I can think of is when your mains trip - then your house neutral is not bonded to earth any more and when the inverter kicks in you sit with the floating neutral problem again.
Maybe my studies/memory is letting me down here, please shoot holes as required