Valid

GB/T 25301-2021Resistance welding equipment - Transformers - General specifications applicable to all transformers (English PDF)

电阻焊设备变压器适用于所有变压器的通用技术条件

Preview PDF

This is a limited preview

Buy now to download the full PDF (51 pages)

Need quotation for your management?

Get a formal quotation for GB/T 25301-2021 in 30 minutes.

Issued by

State Administration for Market Regulation, China National Standardization Administration

Level / Type

National · Recommended

Issue date

May 21, 2021

Implementation date

December 1, 2021

Scope

GB/T 25301-2021 is the English-translated version of 电阻焊设备变压器适用于所有变压器的通用技术条件.

GB/T 25301-2021 is the Chinese standard "Resistance welding equipment - Transformers - General specifications applicable to all transformers".

Its scope clause reads: This document specifies the technical conditions for the following types of transformers applicable to resistance welding equipment. ---Single-phase transformer for AC welding, usually working at 50Hz or 60Hz; ---Single-phase transformer connected to rectifier for DC welding, usually working at 50Hz or 60Hz; ---Single-phase inverter transformer connected to rectifier for DC welding, usually working at 400Hz~2kHz; ---Three-phase transformer connected to rectifier used for DC welding, usually working at 50Hz or 60Hz.

For the purposes of this document, the term transformer can refer to a transformer alone or connected to a rectifier (transformer-rectifier unit). This document is applicable to Type I or Type II protective transformers that comply with IEC 61140.

Note. The requirements of this document can be supplemented by other resistance welding transformer standards, such as ISO 22829 and ISO 10656. Its clauses include terms and definitions.

Found what you need?

Document preview — GB/T 25301-2021

National Standard of the People's Republic of China

Classification: J 64

Issued by: State Administration for Market Regulation, China National Standardization Administration

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbol
5 Structure and additional equipment
5.1 Thermal protection
5.2 Output current induction coil
6 Environment and conditions of use
6.1 General
6.2 Ambient temperature
6.3 Humidity
6.4 Height
6.5 Transportation and storage
6.6 Lifting device
6.7 Temperature of the cooling liquid
7 Test
7.1 Test conditions
7.2 Type test
7.3 Routine test
8 Protection against electric shock
8.1 Insulation resistance
8.2 Dielectric strength
8.3 Calibration of the output current induction coil
8.4 Protection against electric shock during normal use (direct contact)
8.5 Protection against electric shock in the event of a fault (non-direct contact)
8.6 Insulation requirements for class II transformers
9 Thermal rating
9.1 General
9.2 Temperature rise limit
9.2.1 General
9.2.2 Winding
9.2.3 Accessible surface
9.2.4 Other components
9.3 Thermal performance test conditions
9.3.1 General
9.3.2 Test conditions for single-phase AC welding transformers and single-phase transformers connected to rectifiers
9.3.3 Test conditions for single-phase inverter welding transformer connected to rectifier
9.3.4 Test conditions for the three-phase transformer connected to the rectifier
9.3.5 Start of fever test
9.3.6 Duration of the fever test
9.4 Temperature measurement method
9.4.1 General
9.4.2 Embedded temperature sensor method
9.4.3 Resistance method
9.4.4 Surface temperature sensor method
9.4.5 Determination of ambient temperature
9.4.6 Determination of coolant temperature
10 Rated output voltage
10.1 General
10.2 No-load AC voltage (U20)
10.3 No-load DC voltage (U2d)
11 No-load current (I10)
11.1 General
11.2 Measurement methods
12 Short circuit voltage (Ucc)
13 Output current under load conditions
14 Cooling liquid circuit
15 Dynamic characteristics
16 Nameplate
16.1 General
16.2 Description
17 Operating Instructions
Appendix A (informative) Example of nameplate
Appendix B (Normative) Correction of high altitude and cooling medium temperature
Appendix C (informative) Several defined physical concepts and explanations
Appendix D (informative) Model code for AC single-phase transformer
References

1 Scope

This document specifies the technical conditions for the following types of transformers applicable to resistance welding equipment.

---Single-phase transformer for AC welding, usually working at 50Hz or 60Hz;

---Single-phase transformer connected to rectifier for DC welding, usually working at 50Hz or 60Hz;

---Single-phase inverter transformer connected to rectifier for DC welding, usually working at 400Hz~2kHz;

---Three-phase transformer connected to rectifier used for DC welding, usually working at 50Hz or 60Hz.

For the purposes of this document, the term transformer can refer to a transformer alone or connected to a rectifier (transformer-rectifier unit).

This document is applicable to Type I or Type II protective transformers that comply with IEC 61140.

Note. The requirements of this document can be supplemented by other resistance welding transformer standards, such as ISO 22829 and ISO 10656.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations

Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

This document.

ISO 669 Resistance welding Resistance welding equipment mechanical and electrical requirements (Resistancewelding-Resistancewelding equipment-Mechanicalandelectricalrequirements)

ISO 17657-3 Resistance welding welding current measurement Part 3.Current induction coil (Resistance welding-Welding currentmeasurementforresistancewelding-Part 3.Currentsensingcoil)

ISO 17657-4 Resistance welding welding current measurement Part 4.Calibration system (Resistancewelding-Weldingcur- rentmeasurementforresistancewelding-Part 4.Calibrationsystem)

ISO 17677-1 Resistance Welding Vocabulary Part 1.Spot Welding, Projection Welding and Seam Welding (Resistancewelding-Vocabulary-

Part 1.Spot,projectionandseamwelding)

IEC 60085 Electrical insulation heat resistance and representation method (Electricalinsulation-Thermalevaluationanddesig- nation)

IEC 60529 enclosure protection level (IP code) [Degrees of protection provided by enclosures (IP code)]

IEC 61140 Electric shock protection devices and common parts of equipment (Protection against electricshock-Commonas- pectsforinstalationandequipment)

3 Terms and definitions

The following terms and definitions defined by ISO 669 and ISO 17677-1 apply to this document.

3.1 Transformer-rectifierunit

Connect the transformer to the rectifier.

The output circuit of the transformer contains a full-wave rectifier.

GB/T 41861 | GB/T 40337 | CNCA C06-01 | GB/T 25298 | GB/T 25297.2 | […]

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 51 pages — is available in the English PDF.

Referenced standards

Normative references

ISO 669 · ISO 17657 · ISO 17677 · IEC 60085 · IEC 60529 · IEC 61140

Cited by

How to Download GB/T 25301-2021

1
Add to cart
Click "Download PDF" on this page and choose "Buy this standard". You can add more standards before checkout.
2
Checkout
Enter your email and billing details. Payment is processed securely by Stripe (cards or bank transfer). Prefer bank details? Request a quotation (min. order $300).
3
Instant delivery (0–9 sec)
Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4
Invoice included
A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.