1. Introduction Italian regulation requires that all inverters connected to the grid first perform an SPI self-test. During this self-test, the inverter checks the trip times for over voltage, under voltage, over frequency and under frequency – to ensure that the inverter disconnects when require...

2022-03-01

Renac Inverter Temperature De-rating

1. What is temperature derating? Derating is the controlled reduction of the inverter power. In normal operation, inverters operate at their maximum power point. At this operating point, the ratio between PV voltage and PV current results in the maximum power. The maximum power point changes cons...

2022-03-01

Renac Inverter Compatible with High Power PV Module

With the development of Cell and PV module technology, various technologies such as half cut cell, shingling module, bi-facial module, PERC, etc. are superimposed on each other. The output power and current of a single module have increased significantly. This brings higher requirements to invert...

2021-08-16

Isolation Fault Troubleshooting

What’s a “isolation fault”? In photovoltaic systems with a transformer-less inverter, the DC is isolated from ground. Modules with defective module isolation, unshielded wires, defective power optimizers, or an inverter internal fault can cause DC current leakage to ground (PE – protective ...

2021-08-16

Why the overvoltage tripping or power reduction occurs?

1. Reason Why the inverter happens overvoltage tripping or power reduction occurs? It may be one of the following reasons: 1) Your local grid is already operating outside the local Standard voltage limits (or wrong regulation settings). For example, in Australia, AS 60038 specifies 230 volts as ...

2021-08-16

Inverter Compatibility with Different Grid Types

Most countries in the world use a supply of standard 230 V (phase voltage) and 400V (line voltage) with neutral cables at 50Hz or 60Hz. Or there might be a Delta grid pattern for power transportation and industrial use for special machines. And as a corresponding result, most of the solar inverte...

2021-08-16

Solar Inverter String Design Calculations

Solar Inverter String Design Calculations The following article will help you calculate the maximum / minimum number of modules per series string when designing your PV system. And the inverter sizing comprises two parts, voltage, and current sizing. During the inverter sizing you need to take in...

2021-08-16

Why should we increase invert frequency?

Why should we increase the invert switching frequency? The most effect of high invert frequency: 1. With the increase of the invert switching frequency, the volume and weight of the inverter are also reduced, and the power density is greatly improved, which can effectively reduce the storage, tr...

2021-08-16

RENAC Export Limitation Solution

Why we need the Export Limitation Feature 1. In some countries, local regulations limit the amount of PV power plant can be fed-in to the grid or allow no feed-in whatsoever, while allow the use of PV power for selfconsumption. Therefore, without an Export Limitation Solution, PV system cannot be...

2021-08-16