目前中等學校演示用的電流計,大概都是南京儀器廠仿苏联規格略加改變製成的动圈式大型電流計,有0248号及2252号兩种。这两种電流计的構造大致相同,用途一樣,本文僅就0248号加以说明,2252号儀器上附有線路圖和簡明用法說明,本文不予說明。 0248号电流計的体型較大,並且有醒目的标度盤和大的指針,在一般的教室中進行教学演示時,坐在後排的學生也可以在自己的座位上观察清楚,且用途廣泛,是演示用的优良儀器之一。一、用途 0248号大型電流計有三种用途: (1)用作靈敏電流計檢查微弱電流,1.5毫安培,可使指度滿标,按筆者經驗,在銅片、鋅 At present, the ammeter used in the demonstration of secondary schools is probably a large-sized moving coil type ammeter manufactured by Nanjing Instrument Factory with a slight change in the specifications of the Soviet Union. There are two types: 0248 and 2252. The construction of the two ammeter is roughly the same, the same purpose, this article is only 0248 to illustrate the 2252 instrument with a circuit diagram and concise usage instructions, this article will not be described. 0248 current meter larger size, and eye-catching dial and large pointer, teaching demonstration in the general classroom, sitting in the back of the students can also observe clearly in their own seats, and a wide range of uses , Is one of the best instruments for demonstration. First, the use of 0248 large current meter has three purposes: (1) as a sensitive current meter check weak current, 1.5 mA, can make the index full scale, according to my experience in the copper, zinc