Abstract: This paper introduces the application of Acrel DJSF1352-RN DC energy meter in the DC side of a photovoltaic system in Nigeria. It is mainly used to measure the DC current in the photovoltaic system, and cooperate with hall current sensor to measure, communicate and control the circuit system.

        該公司位于尼日利亞，是一家新能源公司。主要在非洲從事光伏發電項目。客戶要使用直流電表，用于光伏系統中直流側的監測計量。

    The company is located in Nigeria and is a new energy company. Mainly engaged in photovoltaic power generation projects in Africa. The customer wants to use DC meters and hall sensors for monitor  current and voltage at the DC side of photovoltaic system.

        DJSF1352-RN導軌式直流電能表，主要針對電信基站、直流充電樁、太陽能光伏等應用場合而設計，該系列儀表可測量直流系統中的電壓、電流、功率以及正反向電能等。在實際使用現場，即可計量總電能，又可計量規定時間段內的電能。檢測的結果既可用于本地顯示，又能與工控設備、計算機連接，組成測控系統。

        儀表可具有紅外通訊接口和RS-485通訊接口，同時支持Modbus-RTU協議和DLT645-97(07)協議；可帶繼電器報警輸出和開關量輸入功能；根據不同要求，通過儀表面板按鍵，對變比、報警、通訊進行設置；具有開關量事件記錄（Modbus協議）、編程和事件設置記錄（645協議）、數據瞬時和定時凍結功能（645協議）、電壓電流功率值記錄功能。

        DJSF1352-RN rail-mounted DC power meter designed for telecommunications base stations, DC charging piles, solar photovoltaic and other applications, this series of meters can measure the voltage, current, power and forward and reverse energy and so on in the DC system.The actual use of the site, you can measure the total power, but also measure the energy within a specified period of time. The test results can be used for local display, but also with industrial control equipment, computers to form a measurement and control system.

        The meter can have infrared communication interface and RS-485 communication interface, and supports Modbus-RTU protocol and DLT645-97 (07) protocol at the same time.The meter can have relay alarm output and digital input function;You can set the ratio, alarm, and communication through the meter panel keys according to different requirements.The meter can have event recording of switch (Modbus protocol), programming and event setting records (645 protocol), instantaneous and timing freeze function of data (645 protocol), value recording function of voltage and current power.

Note：when dual DC input（D）function is selected，if Hall current sensor input is used in current channel,a power supply module shall be provided to supply power to the second Hall sensor;if D function is not provided,the built-in power supply of electric meter can be used.

        客戶有一個太陽能混合動力系統。PV板，電池儲能與柴油發生器電信站，三者連接到同一根母線。客戶想用直流儀表來監測母線的電流電壓。他們的太陽能系統是電信基站，輔助電源是DC48V，電流是DC100A。

        The customer have a solar hybrid system. PV panel, battery storage and diesel generator for a telecom station，All the 3 systems are connected to a single bus bar. They wants to know the watt hour reading from the bus bar using a DC meter. And their solar site is a telecom site. the power supply voltage is DC 48V, the current is DC100A.