California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 5 - Electrical Safety Orders
Group 2 - High-Voltage Electrical Safety Orders
Article 36 - Work Procedures and Operating Procedures
Section 2940.17 - Disconnecting Capacitors and Means for Discharge

(a) Before employees work on capacitors, the employer shall disconnect the capacitors from energized sources and short circuit the capacitors. A means shall be provided to reduce the residual voltage of a capacitor to 50 volts or less within 5 minutes after the capacitor is disconnected from the source of supply. The employer shall ensure that the employee short circuiting the capacitors waits at least 5 minutes from the time of disconnection before applying the short circuit.

(b) A discharge circuit shall be provided with automatic means of connecting it to the terminals of the capacitor bank after disconnection of the capacitor from the source of supply. The windings of motors, or transformers, or of other equipment directly connected to capacitors without a switch or overcurrent device interposed shall meet the requirements of subsection (a) above.

(c) Capacitors shall not be worked on until after they have been short circuited and grounded. The employer shall short circuit any line connected to capacitors before the line is treated as deenergized. The internal discharge device provided in capacitors shall not be used as a substitute for externally short circuiting and grounding capacitors.

(d) Before employees handle the units, the employer shall short circuit each unit in series-parallel capacitor banks between all terminals and the capacitor case or its rack. If the cases of capacitors are on ungrounded substation racks, the employer shall bond the racks to ground.