Tenaga Nasional Berhad

Table 2.3.4.1: Voltage limits on switching of load
Load Starting/Switching
Limit of Voltage
Change
Starting/switching once or twice a year 6%
Infrequent single starting/switching or
disconnection of Load – once in two hours
or more hours. Including capacitor or
reactor bank
Frequent starting/switching and/or
disconnection of Load (e.g., Many times
in a day)
3%
1%
2.3.5 Voltage Fluctuations and Flicker
2.3.5.1 The limits of Flicker that are acceptable on the distribution system are in accordance with the “Engineering
Recommendation P28, Issued by The Electricity Council of UK in 1989 entitled Planning Limits for Voltage
Fluctuation Caused by Industrial, Commercial and Domestic Equipment in the United Kingdom”. TNB uses the
procedures contained in this document to plan the connection of Fluctuating Loads and applies the limits therein
in measuring and monitoring the levels of Flicker at such points of connection.
2.3.5.2.2 In accordance with the “Engineering Engineering Recommendation P2”, P2”, voltage fluctuations at a Point of Common
Coupling with a fluctuating Load directly connected to the Distribution System shall not exceed:
(a) % of the voltage level for step changes, which may occur repetitively. Any large voltage excursions other
than step changes or less frequent step changes may be allowed up to a level of 3% provided that this
does not constitute a risk to the distribution system or, in TNB’s view, any other party connected to the
distribution system.
(b) The planning limits for the Short and Long Term Flicker Severity applicable for Fluctuating Loads connected
to the distribution system are as set out in the table below.
TENAGA
NASIONAL B E R H A D
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