In equipment and machnery which include inching and plugging (negative - phase braking), make and break of large starting rush current of motor will occur frequently. Category AC4 is applied for such usage. The rating of electromagnetic contactor is AC3. However, Category AC4 can be applied by lowering the rating. Application examples for motors when assuming that starting rush current (inching current) of the motor is about 6 times that of the rated operational current are shown in Tables 1 and 2.
| Motor capacity (kW) |
Inching ratio 50% | Inching ratio 75 - 100% | ||||||
|---|---|---|---|---|---|---|---|---|
| Electrical life 0.1 million times |
Electrical life 0.5 million times |
Electrical life 0.1 million times |
Electrical life 0.5 million times |
|||||
| 200-240V | 380-440V | 200-240V | 380-440V | 200-240V | 380-440V | 200-240V | 380-440V | |
| 0.1 | H10C | H10C | H10C | H10C | H10C | H10C | H10C | H10C |
| 0.2 | ||||||||
| 0.4 | ||||||||
| 0.75 | H20 | H20 | H20 | |||||
| 1.5 | H25 | H20 | H20 | H35 | ||||
| 2.2 | H20 | H35 | H25 | H25 | H20 | H50 | H35 | |
| 3.7 | H25 | H20 | H65C | H35 | H35 | H25 | H80C | H50 |
| 5.5 | H35 | H25 | H80C | H50 | H65C | H35 | H150C | H65C |
| 7.5 | H50 | H35 | H150C | H65C | H80C | H50 | H80C | |
| 9 | H65C | H50 | H80C | H65C | H200C | H150C | ||
| 11 | H80C | H150C | ||||||
| 13 | H65C | H200C | H150C | H80C | H250C | |||
| 15 | H150C | H150C | H300C | |||||
| 18.5 | H80C | H250C | H200C | H400C | H200C | |||
| 22 | H150C | H300C | H200C | H250C | H600C | H300C | ||
| 30 | H200C | H600C | H250C | H300C | H200C | H400C | ||
| 37 | H250C | H200C | H300C | H600C | H300C | — | H600C | |
| 45 | H300C | H250C | — | H600C | H600C | — | — | |
| 55 | H600C | H300C | — | — | — | — | — | — |
| 75 | — | H600C | — | — | — | — | — | — |
| Motor capacity (kW) | Plugging | |||
|---|---|---|---|---|
| Electrical life 0.1 million times |
Electrical life 0.5 millioin times |
|||
| 200-240V | 380-440V | 200-240V | 380-440V | |
| 0.2 | H10B-R | H10B-R | H10B-R | H10B-R |
| 0.4 | ||||
| 0.75 | H20-R | H20-R | ||
| 1.5 | H20-R | H20-R | H35-R | |
| 2.2 | H25-R | H50-R | H35-R | |
| 3.7 | H35-R | H35-R | H80C-R | H50-R |
| 5.5 | H65C-R | H50-R | H150C-R | H65C-R |
| 7.5 | H80C-R | H65C-R | H80C-R | |
| 11 | H150C-R | H80C-R | H200C-R | H150C-R |
| 15 | H150C-R | H300C-R | ||
| 18.5 | H200C-R | H400C-R | H200C-R | |
| 22 | H250C-R | H600C-R | H300C-R | |
| 30 | H300C-R | H200C-R | H400C-R | |
| 37 | H600C-R | H300C-R | — | H600C-R |
| 45 | H600C-R | — | — | |
Note
