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

??1.項目概述：Project Overview

??該公司位于沙特，公司主要在當地從事小型光伏發電項目的安裝施工與維護等業務。客戶想要使用直流電表，用于光伏系統中直流側電流電壓的監測計量、通訊，要求電表具有兩路直流電能測量的功能。

??The company is located in Saudi Arabia. The company is mainly engaged in installation, construction and maintenance of small photovoltaic power generation center projects in Bulgaria and surrounding countries. The customer wants to use DC meters and hall sensors or current shunts for monitoring, metering and communication of current and voltage at the DC side of photovoltaic system, and demands that the DC energy meter would be able to measure two channels of DC circuits.

??2.DJSF1352-RN/D儀表簡介 DJSF1352-RN/D DC Energy Meters

??DJSF1352-RN導軌式直流電能表帶有雙路直流輸入，主要針對網絡基站、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；可帶繼電器預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、預警、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）、電壓電流功率峰值、谷值記錄功能。

??DJSF1352-RN rail-mounted DC power meter with double DC input channels, 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), maximum and minimum value recording function of voltage and current power.

??3.型號及功能介紹 Type and Function Description

??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 elecctric meter can be used.

??Pulse constant:

??4.客戶特殊需求Requirements from Customer

??4.1 以下是客戶現場太陽能電板參數：

??The following are the customer's on-site solar panel parameters: