BS 4819-2:1989

Foreword
Committees responsible
Specification
1 Scope
2 Definitions
3 Service conditions
3.1 General
3.2 Altitude
3.3 Temperature of the cooling media
4 Design and construction
4.1 General
4.2 Rating
4.3 Primary circuit
4.4 Secondary circuit
4.5 Electromechanical stress
4.6 High voltage
4.7 Insulation resistance
4.8 Protection against ingress of dust and liquids
5 Tests
5.1 Type tests
5.2 Routine tests
6 Testing
6.1 Temperature rise at thermal rating
6.2 Short circuit secondary current using standard
      load
6.3 Electromechanical stress
6.4 No-load primary current
6.5 Open circuit secondary voltage
6.6 Water pressure
6.7 Water flow
6.8 High voltage
6.9 Insulation resistance
6.10 Protection against dust and ingress of liquids
7 Measurement of temperature
7.1 Temperature test conditions
7.2 Winding temperature at end of test
8 Safety
9 Nameplate
Appendices
A Relationship between transformer operating duty
      cycle and input kVA on any specified tapping
B Calculation of permissible duty cycle from the
      thermal rating
Tables
1 Limits of temperature rise
2 Maximum values for no-load power (So) and no-load
      current (I10)
Figures
1 Secondary standard resistance load for portable
      welding transformer
2 Transformer operating duty cycle and input kVA

Requirements, methods of test, service conditions and rating of single-phase, mains frequency transformers having a primary voltage of 660 V or less.

This Part of BS 4819 specifies the requirements, methods of test, service conditions and rating of single-phase, mains frequency resistance welding water-cooled transformers of the portable type having a primary voltage of 660 V or less.

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.