Categories | Economic 4.5KA, 6kA Regular Series Circuit Breaker |
Model | SFM3-125 DC 125A |
Rated current(A) | 1,2,3,4,6,10,16,20,25,32,40,50,63 |
Frame size Rated current(A) | 63A, 125A |
Number of poles | 1P, 2P |
Breaking current | 10000 |
Time costant | 10 |
Application
● The maximum ambient air temperature does not exceed +40C, minimum is not less than -5C,and the average value does not exceed +35C.
● The altitude of the installation site does not exceed 2000m.
● The relative humidity of the atmosphere does not exceed 50% at the maximum ambient temperature of +40C. Relative humidily at high temperatures can be relatively high. The monthly average maximum relative humidity of the wettest month is 90%, and the monthly average of the month The minimum temperature is +25C and takes into account condensation that occurs on
● Pollution levelis 2.
● Installation categories are I, II.
● Use TH35- 7.5 steel mounting rails for installation.
● The inclination of the mounting surface and the vertical surface does not exceed 5°.
● Screw the wire tight.
Construction and Feature
SFM3-DC DC circuit breaker is composed of outer casing, operating mechanism, thermal release,electromagnetic tripping contact system, arc extinguishing system, etc. It has overload and short circuit protection functions, unique design structure and powerful permanent magnet arc extinguishing system. The product has a short circuit capability of 10kA and a mechanical life of more than 20,000 times. The appearance of the product is beautiful. The mounting rail is a TH35-7.5 standard steel mounting rail, and has the following features: the handle is designed on the front side of the front end, and the operation is safe and strong. Feel comfortable, be sure to pay attention to the "+, -" polarity when wiring, the power supply goes in and out, in line with the characteristics of the power supply line, easy to install, saves the wire.
Technical Data
Table 1 | ||||||
Frame size rated current | Pole | Rated voltage | Rated current | Rated ultimate short circuit capability | Instantaneous release current | |
Breaking current | Time constant | |||||
63 | 1 | DC250V | 1,2,3,4,6,10,16,20,25,32,40,50,63 | 10000 | 10 | 8ln-12ln |
2 | DC500V | |||||
125 | 1 | DC250V | 80,100,125 | 10000 | 10 | 8ln-12ln |
2 | DC500V |
Standard time-current
Table 2 | ||||||
Test | DC test current | Initial state | Time limit | Expected result | Remark | |
a | 1.05ln | Cold state |
t≥1h(ln≤63A) t≥2h(ln>63A) |
No tripping | ||
b | 1.3ln | Right after test number a |
t<2h(ln>63A) t<1h(ln≤63A) |
tripping | ||
c | 8ln | Cold state | t≥0.2s | No tripping | ||
12ln | t<0.2s | tripping |
Wiring diagram
Dimensions
> What is the role of a fuse?
A fuse refers to an electrical device that, when the current exceeds a specified value, uses the heat generated by itself to fuse the melt and disconnect the circuit...
> Precautions for the working principle of molded case circuit breakers
The molded case circuit breaker adopts a heat release contact. When the current exceeds the rated value, the contact is heated, causing the spring force to decrease,...
> The difference between fast fuse and ordinary fuse
Fast fuse is a kind of fuse, fast fuse is used for short circuit protection of semiconductor rectifier components or circuit breakers. Because the overload capacity ...
> The meaning and working principle of RCCB, and a few points you want to know
This article will tell you about the working principle, function, and main structure of residual current circuit breaker (RCCB), and solve customers' concerns about ...