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Update time : 2021-12-21 09:39:08
The following are the most significant provisions of the UL8750 update, which came into effect in November 2021:  

Item 1:


SE5.3 A driver with field-wiring leads, field-wiring terminals, or push-in terminals shall be marked “Use only within an enclosure” or equivalent. The marking may be provided in an installation guide or equivalent accompanying document. 

Item 2

6.7 Polymeric potting compound
6.7.3 Polymeric potting compound that can touch any part of the insulation system of a transformer shall be tested in accordance with Supplement SA – Substitutions or Modification to an Electrical Insulation System in the Standard for Systems of Insulating Materials – General, UL 1446. 
Exception No. 1: This test does not apply if the transformer is not used for the mitigation of the risk of electric shock or is not used to separate Class 2 circuits or LVLE circuits from hazardous circuits. 
Exception No. 2: This test does not apply if the transformer insulation system already includes the potting. 
Exception No. 3: This test does not apply if the insulation system is used up to the temperature permitted for class 105 (A) according to Table 8.1 of this standard. 
Exception No. 4: This test does not apply for thermosetting potting compounds where the insulation system of a transformer utilizes a thermoset varnish which completely encloses the coil windings- preventing the potting compound from making contact with the winding wire insulation.
Item 3

7.2A.2 Grounding 

7.2A.2.7 When the path between the grounding connection means and the ground termination point in the product includes PWB traces, the construction is to be evaluated per the bonding conductor tests in 8.23. 
Item 4

Marking requirement 
1. Identification of the terminals or lead wires for control circuits, Identification of the intended industry or proprietary protocols 
2. Device wired control circuit marked ‘Class 2’ 
3. “CAUTION: More than one power supply present” or equivalent 
4. “Notice: This control circuit is not isolated - see installation instructions” or equivalent 
5. Installation instructions