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12 minutes ago, anotherbrownbear said:

I did ask a question. How does he get the 400V VSD to work off of 1 x 400V supply.

From what i read in his post, In Spain they do have a 400 V single to 400Volt 3 phase inverter. I guess its similar to the ones you sell, but with a different input voltage. Then he takes the incoming single phase , step it up to 400 volt single phase and the inverter does the rest to give the 3 phase 400Volt output. 

So in SA you are correct, he's answer is wrong, but it seems in Spain it is correct..  

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1 minute ago, Jaco de Jongh said:

From what i read in his post, In Spain they do have a 400 V single to 400Volt 3 phase inverter.

Or maybe it is lost in translation. He is probably using a 3 phase VSD and taking only two phases in. That way you can still put put 3 x 400V to the motor as long as the inputs on the VSD is big enough to handle the full power required by the motor.

My VSD at home runs on two phases with a 3 phase 400V motor connected to it. And just yesterday we commisioned a Dual Phase VSD panel for a farmer in the Karoo. He only has two phases coming in from Eskom.

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4 hours ago, anotherbrownbear said:

I am interested in how you supply a 400v VSD with only one phase. 

What you can do, is install a 230v VSD which then gives you 2 x 230V output. The motor then needs to be wired in Delta to change the windings from 400V to 230V three phase.

Yap, but not always windings are accesible as a submersible pump. It is possible to feed a 3x400 Vac driver with only two phases, oversizing VFD. For example, If motor pump is 400x3 Vac 1.5 kW, It is possible to use a 400x3 Vac 2.2 kW VFD feeding two phases. Obviously, It is needed disable phase feed loss failure. I have done a few times, in places where there was a gennie and now there is a PV install. Also a transformer is needed to rise 230 Vac Voltage from inverter to 400 Vac to feed VFD.

Edited by Javi Martínez
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On 2019/02/26 at 6:40 AM, Javi Martínez said:

You can use a resistor, 2200 Ohm 2 W, and quickly reconect.

[ Sorry for the late reply. ]

Yes, use a pre-charge resistor! It can even be wired to a switch, or for the ultimate luxury, to a contactor or relay controlled by a small computer. All rated for at least 60 VDC, of course.

I prefer a smaller valued resistor, like 3.3 Ω, for a nice quick start.  It needs to be about a 50 W, high pulse power model (aluminium cased). Regardless of resistance, they all dissipate the same energy, the same amount of energy that is stored in the capacitors. So you may as well have a fairly quick pre-charge, as long as your switch / relay / contactor can handle the current.

As well as being bad for the capacitors, the high surge current is also hard on the fuse contacts, or wherever the arc happens. Eventually, it can tarnish and lose metal and the contact can become high resistance. 

When I press my green start button, no less than seven contactors come on in quick succession (clack clack ... clack). One of those is for pre-charging the inverter capacitors. It's not good for the capacitors to charge at thousands of amps, as well as the other hazards. When I mash my big red switch™, there is a big clunk and they all drop out together, isolating AC in, AC out, PV in (both poles, both solar charge controllers). At the same time, a contactor in the main switchboard (DB) drops out and my house switches over to mains. All automatic.

It did cost a bit for all the contactors, and took a while to wire up.

Edited by Coulomb
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On 2019/02/26 at 3:04 PM, plonkster said:

The sparks is because the big capacitors inside the inverter has to charge up, and when they are completely discharged they behave like a dead short (hence the spark). What you do to avoid the spark is "precharge" it, that is charge it slowly through a resistor. And that is what @Javi Martínez and @Ingo is talking about. Once the caps are charged, you can connect the cables without any sparking

Does the caps keep the charge if the inverter was switched of for a few hours but the batteries was not disconnected .

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43 minutes ago, Chris Louw said:

Does the caps keep the charge if the inverter was switched of for a few hours but the batteries was not disconnected .

This really depends on the type of inverter. I can tell you with my old Victron Multiplus Compact... it would hold (at least some) charge for days even if completely disconnected.

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12 hours ago, plonkster said:

This really depends on the type of inverter. I can tell you with my old Victron Multiplus Compact... it would hold (at least some) charge for days even if completely disconnected.

Thank you . Will do a test next time I switch the inverter off .

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23 hours ago, Aizen79 said:

Hi guys...a quick one....when installing the Victron BMV....do we need to move the Multiplus temp connect from the negative side of the battery bank?

No. The temperature sensor should be connected to a pole of the battery because it needs to measure the temperature of the battery itself, not the air temperature or shunt temperature of wherever else you might put it.

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1 hour ago, plonkster said:

No. The temperature sensor should be connected to a pole of the battery because it needs to measure the temperature of the battery itself, not the air temperature or shunt temperature of wherever else you might put it.

Thanks...

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On 2019/02/26 at 7:46 PM, anotherbrownbear said:

Or maybe it is lost in translation. He is probably using a 3 phase VSD and taking only two phases in. That way you can still put put 3 x 400V to the motor as long as the inputs on the VSD is big enough to handle the full power required by the motor.

My VSD at home runs on two phases with a 3 phase 400V motor connected to it. And just yesterday we commisioned a Dual Phase VSD panel for a farmer in the Karoo. He only has two phases coming in from Eskom

Two phases or a mono phase system? It is not the same. 

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On 2019/02/27 at 9:54 PM, Chris Louw said:

Does the caps keep the charge if the inverter was switched of for a few hours but the batteries was not disconnected .

With an Axpert the caps remain powered even it the inveter is switched off. The built in SCC also continues to function even if the inverter is off.

 

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Morning guys, a quick one...with the 48/3000/35 Easysolar, does the the battery bank get 105amp charging current[35amp from the inverter and 70amp from the 2 charge controllers] when fully connected or is there an internal control to limit the current assuming there’s no Venus device or mppt control....

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1 hour ago, Aizen79 said:

... internal control to limit ...

On the inverter itself you can set the max charging current if there is no VenusGX or CCGX or MPPT.

You need a MK3 cable and the Victron software to do that.

If there is a CCGX or VenusGX, you set the MPPT to max charging setting the charging limit on the VenusGX / CCGX. It is a tricky one this. you need to make sure if the VenusGX / CCGX is off or disconnected, that the panels are switched off. 🙂 

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54 minutes ago, The Terrible Triplett said:

On the inverter itself you can set the max charging current if there is no VenusGX or CCGX or MPPT.

You need a MK3 cable and the Victron software to do that.

If there is a CCGX or VenusGX, you set the MPPT to max charging setting the charging limit on the VenusGX / CCGX. It is a tricky one this. you need to make sure if the VenusGX / CCGX is off or disconnected, that the panels are switched off. 🙂 

Noted...I need to get a Venus device before getting the panels....right?

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16 minutes ago, Aizen79 said:

I need to get a Venus device before getting the panels....right?

I would yes, for then you have ESS functionality.

VenusGX is the better option than a CCGX yes. Better hardware.

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Plonkster, The Terrible Triplett...Victron gurus...have noticed my Multiplus has a faint continuous ‘inverter’ led pulsation. The mains and absorption leds are on. Absorption is set for 8 hours.Is this normal?

Today my setup got its first trial....mains were off for 11 hours and the battery  bank dropped to 83.7%

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11 minutes ago, Aizen79 said:

continuous ‘inverter’ led pulsation

It's normal. When it is tying with the grid, the mains and charging LEDs are on, and the inverter led pulses. When it is in bypass the LED stops pulsing. When it is inverting (grid disconnected) the LED is on solidly.

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13 minutes ago, plonkster said:

It's normal. When it is tying with the grid, the mains and charging LEDs are on, and the inverter led pulses. When it is in bypass the LED stops pulsing. When it is inverting (grid disconnected) the LED is on solidly.

Thanks for your very quick response 

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