A MOLDED CASE CIRCUIT BREAKER BASE

Abstract

Present application relates to a molded case circuit breaker base comprising a terminal section, an arc extinguish section, a contactor section, an operation section and a tripping section, characterized in that the molded case circuit breaker base is made of a thermoplastic composition having a thermally conductivity of 1.0-5.0 W/(m*K) in plane and 0.5-2 W/(m*K) through plane measured according to ASTM E1461; wherein the molded case circuit breaker base is portioned into several phase chambers; wherein the circuit breaker base has one phase chamber, two phase chambers, three phase chambers or four phase chambers.

Claims

1. A molded case circuit breaker base comprising a terminal section, an arc extinguish section, a contactor section, an operation section and a tripping section, characterized in that the molded case circuit breaker base is made of a thermoplastic composition having a thermal conductivity of 1.0-5.0 W/(m*K) in plane and 0.5-2 W/(m*K) through plane measured according to ASTM E1461; wherein the molded case circuit breaker base is portioned into several phase chambers; wherein the molded case circuit breaker base has one phase chamber, two phase chambers, three phase chambers or four phase chambers.

2. The molded case circuit breaker base according to claim 1, wherein the thermoplastic composition comprising: 20-70 wt. % of base polymer; 10-30 wt. % of thermally conductive and electrically insulating filler; 10-30 wt. % of glass fiber; 10-25 wt. % of flame retardant agent; 0-20 wt. % of additional additives; relative to the total weight of the composition.

3. The molded case circuit breaker base according to claim 2, wherein the base polymer is one or more selected from the groups consisting of polyamide, polyester, PPS and/or polyether.

4. The molded case circuit breaker base according to claim 3, wherein the polyamide is selected from the groups consisting of polyamide 6, polyamide 46, polyamide 56, polyamide 66, polyamide 410, polyamide 510, polyamide 610, polyamide 6T, polyamide 8T, polyamide 9T, polyamide 10T, and co polyamide thereof; co polyamide of polyamide 6T, polyamide 8T, polyamide 9T and polyamide 10T with other polyamide such as polyamide 4T, polyamide 5T, polyamide 7T, polyamide 12T; co polyamide of polyamide 6T, polyamide 4T and polyamide 46 (polyamide 6T/4T/46) copolyamide of polyamide 6T, polyamide 66 and polyamide 46 (polyamide 6T/66/46), copolyamide of polyamide 6T, polyamide 5T and polyamide 56 (polyamide 6T/5T/56) and co polyamide of polyamide 6T, polyamide 66 and polyamide 56 (polyamide 6T/66/56); more preferably, the polyamide is polyamide 6, polyamide 46, most preferably the polyamide is polyamide 46.

5. The molded case circuit breaker base according to claim 1, wherein the volume rate of insulation resistance of the thermoplastic composition ranges from 1E10 to 1E16 m measured according to IEC 60093.

6. The molded case circuit breaker base according to claim 1, wherein the flame retardant rating of the thermoplastic composition is V-2, V-1 or V-0, measured according to IEC 60695-11-10.

7. The molded case circuit breaker base according to claim 1, wherein the tensile modulus of thermoplastic composition ranges from 7000 to 17000 MPa, measured according to ISO 527-1/-2.

8. The molded case circuit breaker base according to claim 1, wherein the break elongation of the thermoplastic composition ranges from 1.0 to 3.0%, measured according to ISO 527-1/-2.

9. A molded case circuit breaker comprising a molded case circuit breaker base according claim 1, comprising contactors, terminals, operation mechanisms and trippings, wherein the contactor is connected with the base directly or via a thermal conductive media; wherein the thermal conductive media is metal, thermal conductive glue or other thermal conductible composition, wherein the thermal conductivity of the thermal conductive media is higher than 1 W/(m*K).

Description

FIGURES

[0032] FIG. 1 is a schematic of a molded circuit breaker base.

1 represents terminal section; 2 represents arc extinguish section; 3 represents contactor section; 4 represents operation section; 5 represents tripping section.

[0033] FIG. 2 is a schematic of a molded circuit breaker base.

[0034] FIG. 3 is the average temperature increasing curve of the phase A, B, C of the two MCCB obtained from examples.

[0035] FIG. 4 is the temperature increasing curves of phase B upstream of the two MCCB obtained from examples.

EXAMPLE 1

[0036] A three phases (phase A, phase B, phase C) MCCB base was molded by using DSM Stanyl TC168 (thermal conductivity of 2.1 W/(m*K) in plane and 0.9 W/(m*K) through plane). The obtained MCCB base comprised terminal section, arc extinguish section, contactor section, operation section, and tripping section.

MCCB-1 was assembled by using the obtained base and the static contactors were connected to the base via thermal conductible glue (SialnexST0903 thermal conductivity of 30 W/(m*K)).

EXAMPLE 2

[0037] A three phases (phase A, phase B, phase C) MCCB base was molded by using DSM Stanyl TE250F6 (thermal conductivity of 0.4 W/(m*K) in plane and 0.35 W/(m*K) through plane) in the same mold as used in example 1.

MCCB-2 with same rated power as MCCB-1 was assembled by using the base obtained from example 2.
Temperature increasing of the terminals of the MCCB-1 and MCCB-2 under different power consume were measured according to IEC60947-2 7.2.2. and the results were showed in FIG. 3 and FIG. 4.

CONCLUSION

[0038] The temperature increasing of the terminals of MCCB-1, comparing with MCCB-2, under the same power consuming, is about 5K lower. This result means that, comparing with MCCB-2 base, MCCB-1 base has a better heat dissipation property.