Mecer 5kW-48V MKS II

[Antony]

Any issues with this inverter I should be careful of?

I see its being "marketed" as off-grid.

Also anyone know the Centurion Solar inverter control module "for maximising the potential of the Pylon batteries."

 

 

Edited September 21, 2018 by Antony

[Jaco De Jongh]

13 minutes ago, Antony said:

Any issues with this inverter I should be careful of?

I see its being "marketed" as off-grid.

If you want to be off-grid, I guess there is nothing wrong with this inverter. If you want to connect in Hybrid mode and use all available power sources at once, you need to look at something different. The only other thing bothering me about this is the legal aspects that's been surfacing in other posts recently. Please look at Is Your System Legal. Look at the issues @ebrsais facing with his axperts, and those regulations might carry over to  other parts of the country. If it does, you might land up wanting or needing to replace the Axpert. I feel the Unit has proved itself to be reliable, but does it suite your overall needs?

[Guest]

2 hours ago, Antony said:

I see its being "marketed" as off-grid.

A very salient point to ponder on. 

[Antony]

1 hour ago, Jaco de Jongh said:

 but does it suite your overall needs?

I want to be able to supplement from the grid should the load exceed my PV generation.

I want to "feed" my daytime consumption, including pool pump - 0.75kW via PV and have backup for nighttime essential loads.

Tuesdays is washing day so the load tends to creep up a bit on these days.

I have a separate DB for the "living area" and a grid-only DB for the heavy loads like oven, I have a gas stove, some plugs, etc.

My total daily consumption is down to 30kW per day with daytime being the highest % of this.

I don't seem to exceed 4kW spikes at any given time, except when the bipeds use their hairdryers, which will be on the grid-only DB anyway.

I was considering the Goodwe 5048D-ES Hybrid Solar Inverter (double the price of the Mecer / Axpert) with Pylontech batteries.

https://www.inverter-warehouse.co.za/products/goodwe-pylontech-4-8kw-5-2wp-solar-panels

but not necessarily from Inverter Warehouse, I'm sure someone on the forum will advice a cheaper route ;-)

[Jaco De Jongh]

17 minutes ago, Antony said:

Goodwe 5048D-ES Hybrid Solar Inverter (double the price of the Mecer / Axpert)

Hybrid yes. Because it doesn't switch between loads, it mixes them, so if your demand is 2kw and pv is 1kw, it will take the pv, add 1kw from grid and supply the 2kw load. you only pay for 1kw. But with axpert, it goes to grid and you pay for 2kw, while the 1kw PV is waiting to be used again, going to waste.  

Rather chose a Hybrid from the approved list, it is more expensive, but for a reason. Long run you will see the benefits and when regulation comes your way, you are already halfway there. 

I will rather take the Goodwe

 

[Jaco De Jongh]

19 minutes ago, Antony said:

I'm sure someone on the forum will advice a cheaper route

Check your PM

[Antony]

9 minutes ago, Jaco de Jongh said:

if your demand is 2kw and pv is 1kw, it will take the pv, add 1kw from grid and supply the 2kw load. you only pay for 1kw.

This is exactly what I want to do.

[Jaco De Jongh]

1 minute ago, Antony said:

This is exactly what I want to do.

Then Hybrid is your answer. 

[Antony]

12 minutes ago, Jaco de Jongh said:

I will rather take the Goodwe

 

And battery management is also sorted or should I still consider a BMV702 for the Pylontechs?

[Jaco De Jongh]

5 minutes ago, Antony said:

And battery management is also sorted or should I still consider a BMV702 for the Pylontechs?

I am not 100% sure about Goodwee's battery management capabilities, but f you also plan Data management software like ICC then battery management will be taken care of. 

I don't think a 702 is really useful for Pylontech Battery's. 

[Fuenkli]

34 minutes ago, Antony said:

I was considering the Goodwe 5048D-ES Hybrid Solar Inverter

please be aware that if you have a single phase 60A Eskom power supply this inverter is exceeding the maximum kW allowed by most municipalities.

[Antony]

9 minutes ago, Fuenkli said:

please be aware that if you have a single phase 60A Eskom power supply this inverter is exceeding the maximum kW allowed by most municipalities.

This is just not fair...

[Jaco De Jongh]

13 minutes ago, Fuenkli said:

please be aware that if you have a single phase 60A Eskom power supply this inverter is exceeding the maximum kW allowed by most municipalities.

 

3 minutes ago, Antony said:

This is just not fair...

Goodwe has a 3.6kw model as well, but before you buy one, the new regulations states that you can apply for approval to install a bigger inverter, but application needs to happen prior to installation. Maybe go see the counsel first, you've got nothing to loose. 

[___]

3 hours ago, Antony said:

Also anyone know the Centurion Solar inverter control module "for maximising the potential of the Pylon batteries."

I'm pretty certain it's just a Raspberry Pi running ICC.

Look, I know I am biased, but I have serious trust issues with any store that puts a Voltronic inverter up in the showroom :-) Maybe if you keep them in the back... or if you're a Voltex or an AC/DC (both those stores have one up on Display in my home town... complete with the Silver calcium jobbies... but they are excused... they are AC shops and don't know anything about solar).

[Antony]

If my PV array is 6600 watts (20 x 330w panels) and the inverter is rated at MAX input of 6500 watts, does it mean the inverter will only be able to use 6500 watts or must I reduce the PV <= to 6500 watts?

My real question is will I blow something up if the array output is more than the inverter input?

Question about the 6600 array, will it ever produce 6600? won't there be losses?

I want to make sure I get MAX available power throughout the day, i.e. as close to the inverters rating as possible with solar tracking...

[Coulomb]

58 minutes ago, Antony said:

My real question is will I blow something up if the array output is more than the inverter input?

I doubt that anything will blow up as a result of that slight difference, but wiser heads may contradict me.

58 minutes ago, Antony said:

Question about the 6600 array, will it ever produce 6600? won't there be losses?

It could sometimes produce more than 7000 W, but not for long. Most of the time, they will produce about 80% of rated power near noon and with no shade, and less at other times. I'd say that the manufacturer is referring to 6500 W of nominal photovoltaic power, and the losses would be taken into account already.

The solar controller is a feedback system. If they say 6500 W maximum, I think they mean that they don't guarantee the stability of the control system when it has to try to tame that much power. So it might tend to overshoot the battery voltage it is aiming for, or undershoot as well. If this went on for long, it could damage your battery, or even the inverter. But it's unlikely to happen for long, so I'd say that this minor overload is acceptable. But you have to draw the line somewhere.

Voltronic Power inverters, such as your Mecer, don't have the greatest solar controllers to start with. So I would no push the PV power too much. But as long as you can think of at least one non-ideality (not quite optimal tilt, some shading, etc), then you should be fine with just 100 W over the limit. But you did mention solar tracking; do you really want to do that? Few seem to consider the results worth the effort.

[Antony]

2 minutes ago, Coulomb said:

But you did mention solar tracking; do you really want to do that? Few seem to consider the results worth the effort.

I don't want to go the tracking route at all, I would rather buy more panels, I have enough roof space for 20 panels, and another 18 on the garage roof.

I just want to ensure that if I have "more" panels than the inverter can handle, my aim being to allow for shade, early morning, angle and the like... 

[Coulomb]

Though I note that this page says the maximum PV power is 4500 W:

https://thepowerstore.co.za/products/axpert-mks-5kva-5kw-80a-mppt-48v-solar-inverter

That's the same inverter as the title of this topic, right?

[Antony]

1 hour ago, Antony said:

 with solar tracking...

Should have read WITHOUT solar tracking

[Antony]

1 minute ago, Coulomb said:

Though I note that this page says the maximum PV power is 4500 W:

https://thepowerstore.co.za/products/axpert-mks-5kva-5kw-80a-mppt-48v-solar-inverter

That's the same inverter as the title of this topic, right?

I'm considering the Goodwe 5048D-ES instead

[Chris Hobson]

I would take a Goodwe over an Axpert and I have two Axperts.

[Antony]

2 minutes ago, Chris Hobson said:

I would take a Goodwe over an Axpert and I have two Axperts.

But would I be ok if my PV array "produced" more than the MAX PV input of the inverter by a few 100 watts?

[Coulomb]

11 minutes ago, Antony said:

But would I be ok if my PV array "produced" more than the MAX PV input of the inverter by a few 100 watts?

It won't produce more than the inverter can handle, except perhaps for brief transients if the control system becomes unstable.

It seems that the Goodwe will draw a maximum of 5400 W (its "DC power" rating), and it's recommended that no more than 130% of that figure is connected, i.e. you would be safe with 130% x 5400 = 7,020 W.

[Chris Hobson]

Hi Antony

I have an Axpert which has an MPPT with a 3000W max. Regularly it goes over 3000W with cloud edge effect etc. Only for a few minutes at a time. @Sidewinder had a single Axpert  that he had 3750 W of panels on. You can safely over size you array by about 25-30%. 

The Goodwe which is a nominal 4.6kW inverter can handle 6500W of panels an oversizing of  about 40%.

This has been discussed before search oversizing here on the forum and there are numerous threads.

[___]

2 hours ago, Chris Hobson said:

You can safely over size you array by about 25-30%.

Most MPPTs will simply register an overcurrent event and shut down, then start a new sweep/scan from the bottom. Some higher end MPPTs have a current clamp and will simply limit the output current to the max without restarting. I usually don't advise oversizing too much, for example if you oversized by 200%, overcurrent events became quite severe beasts. At some point, you will blow something :-)