On 10th February 2010, Tenaga Nasional Berhad (TNB) organised a half day technical briefing session on new compact substation planning policy and new 11/0.4kV substation  layout at Wisma TNB, Petaling Jaya.  It aimed to brief on TNB’s new policy in the use of compact substations of 500kVA supplying electricity to new housing schemes for domestic consumers and the new layout design of  11/ 0.4kV substation.  The session was chaired by Tn Hj Ismail Din (Senior General Manager, Engineering Department, TNB Distribution).

The briefing was extended to the members of TEEAM, the Association of Consulting Engineers Malaysia (ACEM) and the Real Estate and Housing Developers’ Association (REHDA).  Some 100 participants attended the technical briefing.

Ms Tan Siew Hwa (TNB Senior Engineer, Engineering Department) gave two powerpoint presentations on “Planning Design Policy using 500 kVA Compact Substation” and “New Layout Design of 11/0.4 kV in TNB Distribution”.

The new planning design policy arises because there has been a lot of requests on compact substation installations in new supply development, replacing the conventional substations due to land scarcity and simplicity in construction.  Thus, it triggered TNB to look into reviewing its current policy on compact substation installations. The utility is also taking into consideration the network security and restoration time to customers.

The current policy of all compact substation installation requires pre-approval from Chief Engineer’s office in TNB Headquarters before the planning of network design can proceed.  The new policy of compact substation of 500 kVA capacity is encouraged to be installed for new housing development (domestic customers) only.  Such installation does not require pre-approval before proceeding with planning of network design.  Appropriate distribution network design to ensure security and restoration time to customers will not be affected.

In term of substation land size, land price and building price, there is a vast cost saving for developers to install a compact 500 kVA substation in comparison to the conventional single chamber 500 kVA.  However, developer/customer has the option of choosing conventional substation or compact substation 500 kVA.

For the new layout design of 11/0.4 kV in TNB Distribution, Ms Tan elaborated that there is an urgent need in monitoring the tapping point of current and voltage, as well as kWh meter for LV bulk customers and metering room to be part of TNB substation building.  All LV distribution boards in new substations are to be replaced with feeder pillars as refered in the Electricity Supply Act Reguiation 19(3).

Her presentation covered the new features in the substation layout, new LV bulk customer metering room, connection scheme, roof slab requirement, fire fighting system requirement and fencing requirement.

A copy of the powerpoint presentation can be viewed by members at the TEEAM Library. For detailed information, you may contact Ms Tan Siew Hwa at E-mail: tshwa@tnb.com.my

Good turnout – Some 100 participants attended the technical briefing.