Supply Quality

Voltage Dip

What is a voltage dip?

A voltage dip is not a power interruption because power supply is not interrupted during its occurrence. It is a reduction in supply voltage in the electricity distribution network or in the customer’s installation, lasting from half second to one minute.

Most customers are not affected by a voltage dip but may experience temporary flickering lights. The temporary suspension of in-house supply is caused by the automated activation of the protection device.


Why does it happen?

The reasons of voltage dip on distribution network are various and are mostly due to unforeseen and uncontrollable events. They can originate from high voltage network issues or interconnections issues with mainland China for instance.

The in-house causes of voltage dips are usually due to the switching on of high-current equipment such as starting of refrigerator and air condition compressors etc.


Minimizing Impact of voltage dips

Equipment mostly sensitive to voltage fluctuations will be temporarily impacted, such as elevators, pumping systems, lighting circuits or cooling systems for instance.

Unfortunately, voltage dip cannot be eliminated from the electricity supply network but can be treated at customers’ installation. Customers can protect special devices by installing power conditioners and smart uninterruptable power supplies.

We will be happy to provide your organization more information to assess possible improvement measures to implement in your electricity installation so as to mitigate or minimize the impact of voltage dips.