Лифты

                                                   

                                                    X_L - индуктивная нагрузка

                          ~                       

                                                    полезной нагрузки нет

                        X_L     

                                                     

         U_L                                                             ~             

                                                              X_L                 

                   90⁰                                                                 

                                     I

                                                            

емкостная нагрузка создает угол сдвига фаз 90⁰  
 

                                  I       

          90⁰                            полезной работы нет 
 

         U_C 

                                                      - полезная мощность

                      S                          Вт - активная мощность

                                 Q             - pеактивная

                                              - коэффициент мощности.

                      P                                    

Трехфазный  ток. 

                                        A          четырехпроходная система (с глухозазем-

                                        B          ленной нейтралью и питает смешанную

                                        C          нагрузку)

                                        N

                                                

                                        A      трехвазная система (для равномерной

                                        B      нагрузки)

                                        C 
 

                                     I_л

                                      

                                                                  при равномерной нагрузке

                                              

                                                                 при неравномерной   нагрузке

                                      120⁰                    120⁰                                                   

                                                                  

                                          120⁰                      

                        I_с                           I_в                 

Это основное свойство трехфазного переменного тока.

                         С₁ С₂ С₃

                                                                          С₁ С₂ С₃

                                                                              

      

                   С₆ С₄  С₅                                                     С₆  С₄ С₅ 
 
 
 
 
 

                             I_A                              А                                           

                   I_Ф

                                                     U_л = 380В                                                        

       ⁰                                                                                                          

                                                                                                       

                                                             B 

                                                              C

                                                                 U_Ф = 220В     

                                                             N

Роль  N провода:

1. Выравнивание напряжение.
2. Рабочий для однофазной нагрузки.
3. Защитный нулевой.

 
 
 
 
 

                                                                      A

                            I_Ф                I_A

                                                                      B                              

                                                                       C                      

Мощность  трехфазного тока.

                                  

- коэффициент мощности 
 
 
 
 
 
 

Электрическое измерение. 

                    магнитоэлектрическая – постоянной  цепи

               

                     электромагнитная – переменной  цепи 

 

                             электродинамическая постоянной  и переменой цепи

                    

                      индукционная – переменной цепи      

                            r⁰

                                         I_изм                           

                               R_м     

                                                                      

                            R_доб

                                             
 

 
 
 
 
 
 
 
 
 
 
 
 

Схемы включения  ватметра

                         U^x

                           5A

           I^x              300v                       

                                             300В

                                                     

Схемы включения счетчика. 

 

Транспортеры                                                                   Автотрансформаторы 

                                                                                        ^A

      ~U₁                                    ~U₂                                                                      C

                                                                                                                 R

 

                                  простой и лабораторный ЛАТР

                                                                                       1,2 – 1,5          
 
 
 
 
 
 
 
 

3^х фазный трансформатор.

    _А                                          а

                                                                                ^{Л1                     Л2}

      ^{X                                         x}

     _{В                                          в}                      U₁                                                              U₂

                                                                                              5A

                                                              Трансформатор тока

     ^{у                                       У}                                      Т. Б. перед отключением

                                                              закороти U₁ и U₂   

   ^{С                                         с}                   Трансформатор напряжения

   _{Z                                         z}

                                                              Л1                      Л2 

 

                                                               U₁                              U₂

                                                                                  100В