Standard 5085-3, Edition 1
UL 5085-3

Low Voltage Transformers - Part 3: Class 2 and Class 3 Transformers

UL CSDS Proposal Edition 1 Published Date: June 29, 2012 Last Revision: January 28, 2022

Summary of Topics b5085-3_1_20120629_sum.html

Subject 5085-3

Bulletin Dated: June 29, 2012


The following changes in requirements to the Standard for Low Voltage Transformers - Part 3: Class 2 and Class 3 Transformers, UL 5085-3, are being proposed:

1. Clarification of the Calibration Test of Overcurrent Protective Devices

2. Clarification of Upper Rating Limit for Overcurrent Limiting Device in Class 2 Transformers

3. Correction of Requirements for the Dielectric Voltage-Withstand After Overload Heating Test

4. Reinstatement of Requirements for the Separation of Circuits

5. Correction of Maximum Temperature Rise for Class 120 (E) Insulation Systems

6. Clarification of the Scope Regarding Cord-Connected Transformers

7. Addition of Leakage Current Test for Cord-Connected Class 3 Transformers

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