Yakub Ansari
- Mar 6, 2021
- 3 min read

Delta Zero export device | Delta export limiter | 2021

Updated: Oct 9, 2021

Delta Grid Tie PV Inverters

Delta Energy Systems is Germany based, multi-billion dollar company, founded in 1971 and been producing solar inverters since 1999. Since 2003 Delta Energy Systems is part of Delta Group.

Delta has a range of transformerless grid-tied solar inverters series, RPI from 3kW to 125kW and a DeiCEN series 1 MW to 3MW.

The absence of a transformer leads to higher efficiency, reductions in weight and size and a lower cost due to the reduced number of components.

With Design Ambient temperature of -25 Degree C to + 60 Degree C and Ingress protection class of IP65. Delta makes, Solar string inverters are ideal for installation in harsh conditions.

The cabinet is IP65 rated for outdoor use which means the electronic components are protected against dust and water ingress which reduces the likelihood of damage to components. This is in line with industry standards.

Delta Zero Export Device

On-gird solar power (PV) plant generates excess power when the connected load is lesser than the power generated by the solar power plant (Power generation > Power required).

This excess power is synchronized with grid power hence it can revere the power flow.

In simple words, power will flow from the PV plant owner’s home to the connected grid [when Solar power generation > Power required by connected load].

With ZED Advance Delta gird tie inverters can be programmed to restrict the excess power generation. Hence provide Zero Export solution to solar plant owners.

ZED Advance is a programmable controller with set points, which can detect reverse power flow (from home to the grid) and control the power generation of the solar power plant.

When ZED Advance detects reveres power [solar power generation > Load demand] it ramps down the power generation of the grid-connected PV plant.

To match, load demand = solar power generation

And when the load increases, the ZED Advance will ramp up the solar power production accordingly.

As long as solar power generation is lower than the load demand, ZED Advance won't affect any change in solar power generation. But it keeps monitoring the system.

Setpoints of ZED Advance can be set between 0% to 100%. Where 5% means that the minimum 5% of load will be served by the grid.

If the frequency of load variation is very high, we need to fix the setpoint above 0% the suitable setpoints are 5%, 10% and 15%.

Curious about ZED Advance? We make a whole page on “ZED Advance” go and checkout and it will help you will be able to select the correct solution for your need.

Delta Export Limiter

Export Limitation means limiting the amount of power exported to the grid. Export limiters limit the power generation from the Delta PV inverter so that amount of power to be exported to the grid can be limited.

ZED Advance can also work as an export limiter for Delta make a grid-connected solar inverter.

Circuit Diagram of connecting ZED Advance with Delta make gird tie inverter.

ZED Advance required a Current transformer along with 10 core, 1.5 Sqmm Cable at the incomer from the grid for the load the measurement and 3 core 1.5 Sqmm cable for self-power as shown in the above illustration.

And compares this with the adjustable setpoint of the controller.

ZED advance also required LAN cable (cat 6) to communicate with Delta Solar Inverter as well as a web portal (for online monitoring).

When the consumption from GRID is above this set point, the solar energy will be increased, when the consumption is below this set point, the solar energy will be reduced.

Key features of ZED Advance