No. 6798 Linhai Road, Fengxian District, Shanghai
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Product Overview
The rated insulation voltage of the MM8LR series (dual breakpoint) residual current operation circuit breaker is 1000V. It is suitable for AC 50HZ and has a three-phase four-wire neutral point direct grounding (TT) distribution network with a rated voltage of AC 380V/400V/415V rated current to 630A. It is used to provide indirect contact protection; prevent fire hazards caused by ground fault current due to damage to the insulation of the equipment; and can be used to distribute power and protect the overload and short circuit of the line; it has a protective function for the overvoltage, underreach and phase loss of the line.
Comply with standards: low-voltage switching equipment and control equipment, Part 2: Circuit breaker GB/T14048.2
Model meaning
| Codename | project | Codename | project |
| ① | Company code: Shanghai Muller | ⑤ | Frame grade rated current: Inm: 250A, Inm: 400A, Inm: 630A |
| ② | Product code: plastic shell circuit breaker | ⑥ | Dividing ability: M type, H type, R type |
| ③ | Design code | ⑦ | Pole number |
| ④ | LR: Smart reclosing gate |
Main technical parameters
| Specifications and models | MM8LR-250 | MM8LR-400 | MM8LR-630 | |
| Case frame grade rated current (A) | 250 | 400 | 630 | |
| Pole number | 3p+n | |||
| Rated operating voltage Ue(V) | AC380V/400V415V | |||
| Rated insulation voltage Ui(V) | 1000 | |||
| Rated impact withstand voltage Uimp(V) | 12000 | |||
| Arc distance (mm) | 0 | 0 | 0 | |
| Rated operating short circuit breaking capability Icn (kA) | H | 70 | 85 | 85 |
| R | 100 | 100 | 100 | |
| Rated limit short circuit breaking capability Icn (kA) | H | 70 | 85 | 85 |
| R | 100 | 100 | 100 | |
| Residual current operation characteristics | AC type | |||
| Rated residual operating current I△n(mA) | 30/50/75/100/200/300/500/800/1000/OFF | |||
| Rated short-term withstand current Icw(kA)/s | 10 | 15 | 15 | |
| Remaining action time characteristics | Delay type/non-delay type | |||
| Delay type limit not drive time (s) | 0.06/0.1/0.2 Optional: 2I△n | |||
| Break time(s) | I△n≤0.5;2I△n≤0.2;5I△n≤0.15 | |||
| Automatic reclosing time (s) | 20～60 | |||
| Operating performance (times) | power ups | 1000 | 1000 | 1000 |
| No power | 7000 | 4000 | 4000 | |
| Total times | 8000 | 5000 | 5000 | |
Appearance and installation dimensions
| model | External dimensions | ||||||||||
| Mm8lr | A | A1 | A2 | A3 | B | B1 | B2 | B3 | H | H1 | H2 |
| 250 | 142 | 3*35 | 23 | 35 | 207.5 | 189 | 164.5 | 172.5 | 155 | 75 | 23.5 |
| 400/630 | 185 | 3*45 | 33 | 45 | 305 | 377 | 241 | 250 | 181 | 103.5 | 34 |