CLP FACING QUESTIONS OVER LATEST VOLTAGE DIP
Second incident in week traps at least 152 people in lifts, prompting calls for such ‘unacceptable’ incidents to be factored into punishment system
Authorities ordered CLP Power to submit a report within a month after a second voltage dip in a week trapped at least 152 people in lifts and triggered 16 automatic fire alarms in Kowloon and the New Territories.
Lawmakers called such incidents “unacceptable” and urged authorities to include voltage dips as factors in a punishment mechanism that applied to the city’s two power suppliers.
CLP Power managing director Joseph Law Ka-chun apologised and said the company was investigating the cause and would submit a report within four weeks, as requested by the government.
Law said a high-voltage-equipment failure occurred at Black Point Power Station in Tuen Mun at around 1.29pm when a thunderstorm warning was in effect. It caused a 0.1-second voltage dip in the 400kV power supply system. But he added that the power supply was not interrupted.
He said residents in different areas might have been affected because the dip occurred in a high-voltage system.
“We immediately arranged for engineering personnel to inspect the high-voltage equipment in Black Point Power Station and reported it to the relevant government departments,” he said.
Law added that voltage dips were unavoidable in different power systems, and a CLP team would provide technical support to customers to look into how to reduce the sensitivity of their equipment to such issues.
The Electrical and Mechanical Services Department said CLP had notified it of the incident yesterday afternoon, and that it immediately followed up on the case and sent staff to conduct assessments.
“The government is very concerned about several recent voltage dip incidents,” the department said. “The Environment and Ecology Bureau has requested CLP to provide an explanation to the public and take effective measures to make improvement and has instructed the Electrical and Mechanical Services Department to step up monitoring CLP’s technical and electrical safety performance.”
It had also asked registered lift contractors to report the situation on stuck lifts and send staff to affected areas to help free trapped passengers and reset systems.
The department said it would continue to maintain close contact with CLP and urge it to conduct appropriate follow-up work.
Last Saturday afternoon a voltage dip resulted in 52 reports of people stuck in lifts. CLP said at the time that a preliminary investigation found a hill fire in Shap Pat Heung, Yuen Long, affected overhead electricity pylons.
Lawmaker Michael Tien Puksun said it was unacceptable to have several outages within four months. “It seems that such incidents have gradually become the norm, which is completely unacceptable,” he said yesterday.
Tien noted that by law all new lifts had to be installed with a device causing them to automatically stop and open on the nearest floor when a voltage dip occurred.
He said he would ask CLP to clarify whether it would subsidise the installation of such devices in old lifts when company officials attended a Legislative Council meeting next month to explain two earlier outrages in Tsing Yi.
Tien also urged authorities to consider including incidents of people being trapped in lifts as a result of voltage dips in a punishment mechanism imposed on CLP and HK Electric.
Legislator Gary Zhang Xinyu pointed to the effects of frequent voltage dips on residents as well as sectors with sensitive equipment. He said he planned to push for dips to be included in service indicators to monitor the performance of the two suppliers.
He said failure to meet standards should lead to penalties. “If voltage dips have become so frequent, they are no longer a trivial matter in our daily life,” he said.
Two outages within a week in January prompted authorities to order CLP Power to complete an inspection of its electricity supply system within a month.
The firm submitted two reports to the Electrical and Mechanical Services Department and admitted that deterioration of equipment parts caused the two incidents in Tsing Yi.
The first case, at Nga Ying Chau Street substation on New Year’s Day, was caused by degradation of cable insulation material. On January 7, a partial power supply interruption at On Mei House in Cheung On Estate was the result of a faulty cable joint in an 11kV underground cable.