YZD-12Pre-paid Control Circuit Breaker
1.General description
    To fulfill the necessary of power usage management, to use technique way to solve the difficulty on power cost
recycling especially hard to control the big power user we researched this YZD-12 type outdoor H.V. pre-paid control device. It is used in electric system of AC 50 Hz, voltage 7 .2~12kV as the automatic recloser under pre-paid H.V. measurement or distribution network automation project. The host machine includes ZW8-12 vacuum circuit breaker, dry type voltage transformer and current transformer, integrated installation, the top of case is vacuum circuit breaker, the bottom is transformer apartment, matches with handle opening and closing spring mechanism outside, the control case is installed separately, it could extra install pre-paid ammeter as pre-paid measurement according to user' s requirement, or install it by user. 
    H.V. vacuum circuit breaker is with spring mechanism, mechanical locking, inside case with switching apartment and transformer apartment. It is made of two sets dry type voltage transformers and two sets dry type current transformers of the transformer apartment, meanwhile, the voltage transformer sets dedicated core as the power of opening-closing mechanism, it is small outfit and easy installation. With V/V wire connecting for VT, the current transformer could be done with multi-ratio structure, to fulfill different load requirement. 
The control device is composed with pre-paid ammeter and control circuit, the connection between control device and vacuum switch is by metal-clad cable, achieves the function of using after purchasing, avoids the defaulting of electric cost in valid. 
2.Function and characteristic
a. This system is composed of H.V. measurement control device and vacuum circuit breaker, as a set with disconnecting switch and arrester to fulfill the electric measurement and power pre-purchasing for users.
b.  Adopt electricity meter for measurement and clearing.
c.  Through buying electricity power card for using the electricity, each measurement case matches with one dedicate electricity power card and non-exchange.
d. Data valid for purchasing once, data out automatically after insert card, function with anti-magnetic, anti-static and encryption indecipherability.
e. Pulling out the card and preservation, reserve it for next time using. If damage or loss, compensation could be
available at the sale power department according to user's record.
f. Balanced electricity, used electricity or other power using parameter could be checked from the display screen of the device. 
g. Sound and light alarm when balanced electricity reach the alarming threshold, reminding users to buy electricity in time.
h. It is reliable to break the load current when the purchasing electricity goes into zero, so that get the solution for the worrying about defaulting electricity charge. 
i. Function with anti-stealing electricity. Due to this device adopts outdoor transformer for the measurement, the meter is installed inside the measurement case, so it solves electricity stealing problem radically. 
3.Mechanical property parameter4.Main technical parameter5.International fairs

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