Current through Register Vol. 54, No. 50, December 14, 2024
Section 3a.30 - Electric boilersAppliances required for electric boilers must be attached to the boilers in accordance with the following requirements:
(1) A cable shall be provided for grounding the boiler shell and shall be the same gauge as the incoming power line to the boiler. The cable must be permanently connected and grounded.(2) A suitable screen or guard shall be placed around high-tension bushings with a sign containing a high voltage warning. The screen or guard shall be located to prevent a person from accidentally coming in contact with the high-tension circuit.(3) The power circuit to the boiler must be open when safety valves are adjusted.(4) The power line must be open when the boiler is under steam pressure and the operator is making a necessary adjustment.(5) Safety or relief valves must have a relieving capacity of 3 1/2 pounds per hour for each kilowatt rating.(6) Boiler shell grounding connectors shall be installed in accordance with the following: (i) The NEC, Chapter 4, except that the cable gauge size must comply with paragraph (1).(ii) A conductor will be permanently attached to the boiler shell by suitable lugs, pressure connectors, clamps, or other Department-approved means. Connectors that depend on solder to maintain connection may not be used.