o dng in, in pMy o ch th s

Chng 2

C cu ch th kim

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C cu ch th kim

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C cu t in

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C cu t in

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C cau t ien.1 Nam cham vnh cu 5 Kim ch th 2 Cc t 6 oi trong3 Loi sat non 7 Shunt t4 Khung day

C cu t in

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C cu t in

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C cu t in

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Ch o dng DC. Mq= NBWL I = KqI; Mc= Kc. nhy dng:

SI = d/dI = Kq/Kc= K. Trn thc t:SI = 1/IFS Thang o tuyn tnh. C chnh xc cao. IFS c 50A; Rm c 1K. Cng sut tiu th nh

25 W 200 W; Cp chnh xc cao 0,5%;

C cu t in

C cu t in

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C cu gng quay

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C cu t in

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cd dJ D T

dtdt

+ + =2

2 0

J - momen quan tnh cua khung quay va kimD - hang so em cua he thongTc - momen can do lo xo kiem soat hoac day xoan.

e co s em ung mc th Dphai co ieu kien:

o cD D J T.= = 2

dd

i D

eiR R

=+

C cu t in

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C cu t in

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C cu in t

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Loi ht Loi y

C cu in t

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C 2 loi : Lc ht v lc y. Dng vi c 2 dng in DC v AC. Mq = KqI2; Mc = Kc. Thang o khng tuyn tnh. Tiu th nng lng nhiu hn c cu t in. chnh xc thp hn c cu t in. nh hng sai s do t d. T trng to bi cun dy c tr s nh nn cn c mn

bo v t trnh nh hng ca t trng nhiu. Chu c s qu ti cao. IFS c mA; Rm c vi n vi trm .

C cu in t

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Edison General Electric Co., New York

This is an example of the moving-iron type meter in which a curved rod of iron is drawn into a solenoid carrying the current to be measured. Since the deflections are not proportional to the current, the scale had to be calibrated or a calibration table had to be provided.

In the 1880s meters of this type were used by electric plants for rapid measurements of large currents. This meter has a full-scale reading of 132 amperes. On its glass cover it is labeled "Edison System Aperemeter."

Reference: John T. Stock and Denys Vaughn, The Development of Instruments to Measure Current, Science Museum, 1983, pp.34-36

C cu in ng

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C cu in ng

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Dng vi c 2 dng in DC v AC. L c cu c s phi hp ca c cu t in v

in t. Dng lm b ch th cho vn k, ampe k, watt k.

1 201 .(AC)

T

q qM K i i dtT=

1 2.(DC)q qM K I I=

o dng in, in pMy o ch th sC cu ch th kimC cu ch th kimC cu t inC cu t inC cu t inC cu t inC cu t inC cu t inC cu gng quayC cu t inC cu t inC cu t in C cu in tC cu in tC cu in tC cu in ngC cu in ng