GB/T 13539.4-2016 Low voltage fuses Part 4: Supplementary requirements for fuse links for semiconductor equipment protection
details
1 General Provisions
1.1 Scope and Purpose
The supplementary requirements of this section apply to fuse links installed on equipment with semiconductor devices, which are suitable for circuits with a nominal voltage not exceeding 1000V AC or 1500V DC. If applicable, it can also be used for circuits with higher nominal voltages.
Note 1: This type of fuse is usually referred to as a "semiconductor fuse".
Note 2: In most cases, a part of the combination device can be used as a fuse base. Due to the diversity of devices, it is difficult to make general regulations; Whether the combination equipment is suitable as a fuse base should be negotiated between the user and the manufacturer. However, if independent fuse bases or fuse supports are used, they should comply with the relevant requirements of IEC 60269-1:2006.
Note 3: IEC 60269-6 is specifically designed for the protection of solar photovoltaic systems.
The purpose of this section is to determine the characteristics of semiconductor fuses, so that they can be replaced with other types of fuses with the same characteristics under the same size. Therefore, this section specifically stipulates:
a) The following characteristics of fuse links:
1) Rated value;
2) Temperature rise during normal operation;
3) Dissipated power;
4) Time current characteristics;
5) Breaking ability;
6) Cut off current characteristics and I2t characteristics;
7) Arc voltage characteristics.
b) Type tests to verify the characteristics of fuse links;
c) Fuse link symbol;
d) Technical data to be provided (see Appendix BB).
1.2 Normative References
The following documents are essential for the application of this document. For all referenced documents with dates, only the version with dates is applicable to this document. For any reference document without a date, its latest version (including all modifications) applies to this document.
IEC 60269-1:2006 Low voltage fuses Part 1: General re requirements
IEC 60269-2:2006 Low voltage fuses - Part 2: Supplementary requirements for fuses used by specialized personnel (fuses primarily for industrial use) - Examples of standardized fuse systems A to J(Low-voltage fuses-Part 2：Supplementary requirements for fuses for use by authorized persons(fuses mainly for industrial application)-Examples of standardized systems of fuses A to J)
IEC 60269-3 Low voltage fuses - Part 3: Supplementary requirements for fuses used by unskilled personnel (fuses primarily for household and similar purposes)
Note: The thermal reaction time of the melt may be very short, so the melting of the melt under non sinusoidal current conditions cannot be estimated solely based on the effective current. This situation particularly occurs when the frequency is low and the current has prominent peaks, with relatively long small currents occurring between the peaks. For example, in the use of frequency conversion and traction.
3.10 Temperature inside the shell
The rated value of the fuse link is determined according to the specified conditions. When the actual situation of the installation site (including the air conditions at the installation site) does not meet the specified conditions, the user should negotiate with the manufacturer whether it is necessary to re specify the rated value.
4 Categories
4 Categories
IEC 60269-1:2006 is applicable.
5 Characteristics of fuses
5.2 Rated voltage
For rated AC voltage not exceeding 690V and rated DC voltage not exceeding 750V, IEC 60269-1:2006 applies; For higher voltages, one can choose from the R5 or R10 series in ISO 3.
The fuse link should have an AC voltage rating, DC voltage rating, or VSI voltage rating, and may have one or more of these voltage ratings.
5.4 Rated frequency
Rated frequency refers to the frequency related to performance data.
5.5 Rated dissipated power of fuse link
In addition to the provisions of IEC 60269-1:2006, the manufacturer shall specify the functional relationship between the rated dissipated power and 50% to 100% of the rated current, or the rated dissipated power at 50%, 63%, 80%, and 100% of the rated current.
Note: To consider the resistance value of the fuse link, this value should be determined based on the functional relationship between dissipated power and related current.
5.9 Arc voltage characteristics
The arc voltage characteristics provided by the manufacturer should provide the maximum value (peak value) of the arc voltage as a function of the applied voltage of the circuit where the fuse is located. For communication, the power factor values shall be in accordance with Table 104; For DC, the time constant is specified in Table 105 or Table 106 depending on the DC application or VSI application.
6 signs
6.2 Marking of Fuse Links
6.2 of IEC 60269-1:2006 applies and supplements:
——The identification mark and/or code of the manufacturing plant, from which all the characteristics listed in 5.1.2 of IEC 60269-1:2006 can be obtained;
——Use category, "aR" or "gR" or "gS";
——The combination of fuse (5016) and rectifier (5186) markings as shown in IEC 60417.
7 Standard conditions for design
7.3 Temperature rise and dissipated power of fuse links
The fuse link should be designed to withstand rated current as specified in 8.3 without exceeding the following requirements:
——The temperature rise limit of the hottest metal part on the upper part of the fuse link specified by the manufacturer (see Figure 102 and Figure 103);
——The dissipated power at the rated current specified by the manufacturer.
7.4 Actions
The fuse link should be designed to continuously carry any current value that does not exceed the rated current (see 8.4.3.4).
The "aR" fuse link should be able to break circuits with a current value not exceeding the rated breaking capacity and not less than the current required by the manufacturer to break the fuse link.
For the "gR" and "gS" fuse links within the agreed time:
——When carrying any current not exceeding the agreed non melting current (Inf), the fuse should not melt;
——When carrying any current greater than or equal to the agreed breaking current (If) and equal to or lower than the rated breaking capacity, the fuse link should melt.
7.5 Breaking ability
The fuse link should be able to break any circuit with an expected current between the current specified in 7.4 and the rated breaking capacity at a voltage not exceeding 8.5:
——For communication, the power factor shall not be less than the power factor corresponding to the expected current specified in Table 104;
——For direct current, the time constant shall not exceed the time constant specified in Table 105;
——For VSI applications, the fuse should be able to break the current specified in 8.5 when the time constant is not greater than the value specified in Table 106.
7.7 I2t Characteristics
The I2t value determined according to 8.7 should not exceed the manufacturer's specifications. The pre arc I2t value determined according to 8.7 should not be less than the given value (see 5.8.2.1 and 5.8.2.2).
7.15 Arc voltage characteristics
The arc voltage value measured according to 8.7.5 should not exceed the manufacturer's specifications (see 5.9).
7.16 Special working conditions
Special working conditions, such as high acceleration values, should be negotiated with the manufacturer by the user.
8 experiments
Appendix AA Guidelines for the Coordination of Fuse Links and Semiconductor Equipment
AA. 1 General Requirements
This appendix only applies to fuses used in circuits with semiconductor rectifier circuit characteristics.
This appendix pertains to the performance of fuse links under specified conditions, and does not specify the applicability of fuse links to rectifiers.
Note: It should be noted that fuses used for AC may not necessarily be suitable for DC. When used under direct current, it should be negotiated with the manufacturer. Especially the relationship between AC rated voltage and DC rated voltage cannot be explained in a general way. The instructions on the use of DC in this guideline are incomplete and do not include all important factors when using DC.
The purpose of this appendix is to elaborate on the characteristics that a fuse link should possess from the perspective of its rated value and the characteristics of the circuit it is located in, making this appendix the basis for selecting a fuse link.
AA. 7 Breaking ability
The ability to break non sinusoidal AC currents within the rated value is not a high requirement for fuse links used in semiconductor equipment protection.
For higher voltage values (high-voltage fuses), breaking small currents may also be a problem, but this issue is outside the current range described in this article (see 7.4).
As long as it does not exceed the maximum current rise rate at the rated frequency, frequencies higher than the rated frequency have no effect on the breaking capacity. When the frequency is lower than the rated frequency, the fuse releases energy greater than that at the rated frequency. The relevant information, including the low-frequency test conducted according to 8.5.5.1, can be obtained from the manufacturer.
For DC breaking capacity (see note AA. 1), the energy released from the fuse is generally greater than the energy released at the rated frequency. Only when using a fuse with an AC rated voltage significantly higher than the DC power supply voltage can satisfactory melting be guaranteed. Additional information should be obtained from the manufacturing plant.
AA. 8 Converter
The short-circuit current in semiconductor devices generally involves circuits with several bridge arms. When the fuse is blown, commutation occurs between the arms, which is caused by periodic changes in the AC power supply voltage, thyristor conduction, or arc voltage from another fuse.
Converter affects the action of the fuse by changing the circuit structure, circuit constants, and external voltage (such as increasing arc voltage).
Another type of commutation that may seriously affect the operation of the fuse link is caused by the occurrence of a second fault.
Appendix BB: The manufacturer should provide information on the semiconductor equipment protection fuse links listed in the product manual (sample)
Appendix BB
(Normative Appendix)
The manufacturer should provide information on the semiconductor equipment protection fuse links listed in the product manual (sample)
The following information should be provided separately for AC and DC (if applicable).
a) Manufacturer name (trademark).
b) Product model or catalog number.
c) Rated voltage (see 3.4.1).
d) Rated current (see 3.5).
e) Rated frequency or other frequencies (see 5.4).
f) Rated breaking capacity (under rated voltage and different applied voltages) (see 5.7.2 and 8.5).
g) Pre arc and melting time current characteristics (diagram) and applicable levels (markings), if applicable (see 5.6.1 and 8.4.3.3.1).
h) Pre arc I2t characteristics (see 5.8.2.1 and 8.7.2).
i) The fuse I2t characteristics related to voltage under specified power factor or time constant (see 5.8.2.2 and 8.7.2).
j) Arc voltage characteristics (see 5.9 and 8.7.5).
k) Cut off current characteristics (see 5.8.1 and 8.6).
l) The temperature rise at rated current under agreed test conditions and the specified measurement points (see 7.3 and 8.3.5).
m) At least 50% and 100% of the rated current dissipation power, represented at fixed points or in the form of charts within this range (additional parameters can be 63% and 80%) (see 7.3 and 8.3.3).
n) The minimum operating voltage required for the indicator (see 8.4.3.6).
o) Yun