ST 1-1988 (R1994, R1997)
Withdrawn
SPECIALITY TRANSFORMERS (EXCEPT GENERAL-PURPOSE TYPE)
01-12-2013
07-23-2013
Foreword
Scope
1 Referenced standards & definitions
2 General
Service conditions
Frequency
Effect of altitude on temperature rise
Insulation systems
Designation of voltage ratings of windings
Low frequency dielectric requirements
Losses and impedances
Basis of ratings
Tests
Marking
3 Control transformers
Output and voltage ratings
Dielectric tests
Voltage ratio
Limits of temperature rise
Construction
4 Industrial control transformers
Types
Output and voltage rating(s)
Dielectric tests
Tolerances for regulation
Limits of temperature rise
Construction
Standard application data
5 Class 2 transformers
Types
Output and voltage ratings
Dielectric tests
Temperature rise
Construction
Output limitations
6 Signalling transformers
Output and voltage ratings
Dielectric tests
No-load losses (excitation losses)
Voltage ratio
Limits of temperature rise
Construction
7 Ignition transformers
Ratings
Dielectric tests
Tolerances for voltage ratio
Limits of temperature rise
Construction
Secondary spark-gap and short-circuit current
Air delivery and electrode spacing
8 Luminous-tube transformers
Ratings
Dielectric tests
Tolerances for voltage ratio
Limits of temperature rise
Construction
Application guide
Covers control, machine-tool, Class 2, signaling, ignition and luminous-tube transformers. Contains service conditions, tests, classifications, performance characteristics and construction data for the transformers.
| DocumentType |
Standard
|
| ProductNote |
Publisher update - NEMA 2026 Standards – Removed from purchase for this standard as per advice from publisher dated – 5th Feb 2026
|
| PublisherName |
National Electrical Manufacturers Association
|
| Status |
Withdrawn
|
| IEEE 1290-2015 | IEEE Guide for Motor-Operated Valve (MOV) Motor Application, Protection, Control, and Testing in Nuclear Power-Generating Stations |
| UL 506:14ED 2017-06-02 | Specialty Transformers |
| NFPA 70 : 2017 | NATIONAL ELECTRICAL CODE |