UMTS/GSM Solution for Monitoring of On-roof Solar Panels

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Nowadays, solar energy becomes more and more popular, and it is very easy to see on-roof solar panels in many countries. To monitor the thousands of solar panels, which locate in different places, turns out to be one of the key issues for major manufactures and system integrators. Some traditional network solutions would provide communication media such as cable, which may cost much time and money during infrastructure process. In comparison, using cellular is proven to be a good choice.
Based on years of experience in networking for electric system and deep-seated requirements, InHand Networks proposes the cellular based solution for solar panel monitoring. In the mentioned project below, we provide this solution to one of the major integrators of solar panel system.
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In this project, there were a lot of roofs which located in different districts. On each roof, there were two or three large panels to gather solar energy. The energy would be transformed into electricity and stored in a battery. If the electricity wasn’t used up, it would be transformed into standard electricity by an inverter, which then sent remaining power to the backbone grid. Meanwhile, meters installed with inverter would record how much energy these panels produced and how much energy remained. For each inverter, there was a data log connected with inverter by RS485 bus, and the box involved a lot of serial interfaces connected with sensors which were used to measure status such as temperature of solar panels. Then the data log would make statistics and transmit all the information to the data center every day. All these information would be sent to the monitoring center through UMTS network by using a InRouter711WH01 (IR711WH01) with a valid SIM card. Since UMTS is a high speed wireless network of local mobile network, there’s no need to consider geographic limits during infrastructure process.
A public fixed IP was necessary for monitoring center so that all data could reach the right destination.
Besides, to read different data in each data log, IR711WH01 created a highly secured IPSec tunnel between field site and monitoring center. And the customer could easily know whether the panel was good or not, how much energy the roof produced this month and whatever the customer wanted to know. All the operations were based on easily clicking mouse in the webpage of each data log.
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InHand products InRouter 700 fully meet the requirements of networking for dispersed on-roof solar panels, because:
1.InRouter 700 series can keep robust in harsh outdoor environments:
- Wide operating temperature:-25-70℃, Humidity: 95% RH
- Specially designed for power system, with high-level EMI Immunity
- Power Supply: 12-48V DC
- Long MTBF (over 30 years!)
2.Compact designed, DIN-rail mounted, easy fit into control cabinet;
3.Link detection and self-recovery, can redial to internet if failed;
4.Low power consumption design specially for renewable energy system:
- Peak/Operating < 3.6 W
- Standby < 1.14 W
5.Support VPN (IPSec/PPTP/L2TP/GRE/SSL VPN), provide with high-secured tunnel for UP/DOWN data flow;
6.Proven in years’ practice by high-end customers including China State Grid, ABB, Siemens, Schneider Electric, etc.
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