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Our 10 years of Lithium Iron Phosphate experience shared within thousands of articles, hundrends of tests and examples.


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19.12.2017
 
Mickey Mouse at GWL/Power Training

      

 

Some customers are rather exotic. We had a customer who came to our training in the mask of the Mickey Mouse.  This is not a fun, this is a reality. 

The customer was wearing the Mickey Mouse dress the whole training and was happy to take many photos. 

Simply do not worry, be happy! Everything is possible at GWL/Power!

03.11.2017
 
Internal resistence


 

The value of the internal resistance

Question: In your promotional materials you mention several times that the internal resistance of the LTO cells is “very low”“lower than for the LFP cells”, is “only 1 mOhm and less”. However we have tested the internal resistance and the value is more than 20 mOhm. We think your information is not correct.

Answer:

First, note that the internal resistance of the cell is not a constant value. The internal resistance increases when the cell is fully charged and also increases when the cell is getting discharged. To measure the internal resistance for reference value, you should measure within DOD of 80% to 20%.  This means after you charge the cell to full, you let the cell discharge to 80% first and only after that you perform the tests.

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11.06.2017
 
The GridFree inverters for the energy solutions

 

The GridFree inverters for the energy solutions

The 1000W and 2000W GridFree Smart inverters for energy self-generation. 

26.04.2017
 
Monitoring of more GF-YC500T connected on more phases

Question:

Can I monitor multiple microinverters GF-YC500T connected to different phases by a single ECU monitoring gateway?

Answer:

Yes, enter the identification codes of all your microinverters placed on the label on the bottom of the microinverter after you will installed the ECU monitoring gateway. The gateway will communicates with all microinverters on all phases.

 

 

13.10.2016
 
FAQ: What is a GridFree Solution

 

FAQ: What is a GridFree Solution

Question: What is the difference between the GridFree and the Grid-tied installation?

There are basically just two possible types of installations:  Grid-tied and Off-Grid.  

The grid-tied installation means the inverters work in synchronization with the AC grid and supply the energy to the Grid.  The off-grid installation means the inverters product energy for the consuming equipment (appliances), they do not connect with the grid, or even must not be connected with the grid (by the technical requirements).  The off-grid installation usually requires batteries to provide a continuous energy supply.

The GridFree is one type of a Grid-tied installation. The only difference between the commercial grid-tied installations (typically requiring an energy producer license) is that the GridFree installation does not send any surplus energy to the outside grid. In a proper GridFree installation all energy is consumed locally. The GridFree installation is in fact reducing the consumption from the grid by providing self-produced energy.

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09.08.2016
 
FAQ: Adding the solar microinverter to the central inverter

 

 

FAQ: Adding the solar microinverter to the central inverter

Question: I have a permit to connect a 2 kWp solar installation. At this time I have a 1.5 kW inverter. I consider connecting another set of two 250Wp panels with microinverters to increase from 1.5kW to full power of 2 kW. Are the microinverters from GWL compatible with my solar inverter? Will they work together?

Answer: Yes, these inverters will work together on the 230V AC line. They all work on the same AC line and they follow the same international standards (in EU defined by EN50438 norm). So it is possible and very easy to “mix” various inverters on the AC line together.

Your idea is very clever and we recommend to all customers: With microinverters it is possible to add additional solar panel or panels to the existing installation (with other inverters) to get the full maximal power peak that is permitted by your grid license. As there is no change of your original installation, there is no need to update your license or permit from the Grid operator. This expansion of existing solar installations is also called solar retrofitting.

03.08.2016
 
Understanding the EN 50438 for MicroInverter Operation

 

Understanding the EN 50438 for MicroInverter Operation

The EN 50438 gives the specifications of the Grid parameters. The microiverters are required to operate within the limits of this EN standard.

The parameters mean if the grid frequency is above 52 Hz or bellow 47.5 Hz, the microinverter has to stop operation in max 0.5 s. 

If the voltage is above 264.5 V or bellow 195.5 V, the microinverter has to stop operation in max 0.2 s.

In case the voltage is above 253 V and bellow 264.5 V for longer that 600 seconds (10 minutes), the microinverter has to stop working as well. (This is required by EN 50160.)

In case the there is no grid (voltage is 0 V or bellow 195.5 V), the microinverter must disconnect in 0.2 seconds. If fact the disconnection time of the microinverter is about 50 ms (0,050 seconds, max 5 half waves of the sine curve.)

Moreover Germany (and some other countries) give a regulation that says that in case that frequency is above 50.2 Hz it is necessary to reduce the power (VDE4105). However this standard applies only for inverters that feed energy to the public grid. It is not applicable for the self-consumption installations.

18.05.2016
 
Small solar panel with the solar micro-inverter

Small solar panel with the solar micro-inverter

Question: I have a 185Wp panel. How will this panel work with a 250Wp microinverter?

Answer: The panel will work with the microinverter only if the voltage of the panel matches  the operating voltage of the inverter. If the voltage matches, the inverter will produce the energy in the amount  provided by the panel.  See the example:

A) The microinverter has the operating voltage (MPPT range) between 24V and 55V. The 185Wp panel has the open voltage 36V and the max point voltage 30V.   This type of panel will work with the microinverter.  When at the full sun shine the panel will provide some 180 watts of energy and the microinverter will convert this energy to the AC output.

B) The microinverter has the operating voltage (MPPT range) between 24V and 55V. The 185Wp panel has the open voltage 18V and the max point voltage 14V.   This type of panel will NOT work with the microinverter.  The voltage of the panel is out of the range of the microinverter.  Tip: you can connect two identical panels in series to increase the voltage – this support article with ideas of regulating the solar power by means of more small size panels used for one micro-inverter.

05.04.2016
 
FAQ: Multiple micro-inverter installation

 

FAQ: Multiple micro-inverter installation

I have a microinverter installation with products from ABC Company. I have 2kW installation (8x250Wp). Now I wish to increase my installation with more inverters. My questions:

1) The products from ABC Company use a PLC communication to work with the gateway. Is the YC-500 and YC-500 gateway compatible with the ABC products and the PLC communication?

No, sorry. There is no compatibility of the products from different manufacturers. Each product has its own protocol and the products cannot be managed together.    

2) Can the ABC products and the YC-500 inverters work on the same AC line (same phase)?

Yes, there are many installations where inverters (and microinverters) from various manufacturers work together in the AC 230V grid line (phase). Since the grid requirements are the same for all products, observing these requirements makes all product compatible on the AC line – for the energy production. (Not for the communication protocols).

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05.04.2016
 
Micro-Inverter –  Combined Energy at Your Hand

 

Micro-Inverter –  Combined Energy at Your Hand

Combining the existing water/wind power plants with additional energy supply from solar panels. 

Smart energy handling with solar micro-inverters, especially for small water power plants: if there is a lot of sunshine, usually there is less water-fall and water-flow. The energy from the sun can be used during sunshine days and the water power generation can be used less or preserved for use at night or during cloudy days.

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