In terms of reliability and power quality, two sections in Chapter 5 of the CenterPoint Energy Tariff approved by the Public Utility Commission of Texas (PUCT) are especially important:
Section 5.2.1 (Liability Between Company and Retail Customers) states CenterPoint Energy will make reasonable provisions to supply steady and continuous delivery service but does not guarantee against fluctuations or interruptions.
Section 5.5.3 (Equipment Sensitive to Voltage and Waveforms) states customers with equipment that may be adversely impacted by voltage fluctuations are responsible for installing the necessary protective equipment to limit the affect of those events.
In addition to the Tariff, the PUCT has two specific Substantive Rules addressing reliability and power quality:
Substantive Rule 25.51 (Power Quality) covers such issues as voltage and frequency variations, harmonics, power quality monitoring and voltage surveys. This rule requires CenterPoint Energy to provide steady-state supply voltage in compliance with the American National Standards Institute (ANSI) Standard C84.1.
Substantive Rule 25.52 (Reliability and Continuity of Service) is similar to Section 5.2.1 of the PUCT-approved CenterPoint Energy Tariff. It states CenterPoint Energy will make reasonable efforts to maintain electric delivery service. In the event of an interruption, CenterPoint Energy shall reestablish service as quickly as possible.