:: Day 3 :: Maintenance & Installation of EFI

Today,I still doing the same thing like yesterday which are installing EFIs and checking on the batteries. We done our maintenance at Ban Guan,Jln Nahu,Taman Mewah and many more.

I learn about the differences of the P/E(Pencawang Elektrik) and PAT(Pencawang Atas Tiang)

A picture of PAT[Pencawang Atas Tiang]


PAT [Pencawang Atas Tiang]:

~ No LVDB @ LV board (it has been replaced by "black box". Number of switch box is depend on the load/consumer at the place.


*pics of black box*





* pics of "anti-clamp" *







"Anti-clamp" which is the thing in red is located about 1-1.5 meters from ground. It is a limit set by TNB as a height that is safe to do any maintanence,repairing including installing any device. That is why,the EFI that need to be install here,must be put below the "anti-clamp".

The cost for building a PAT is much cheaper than a P/E.According to uncle Sundar, one PAT is cost around RM14k compared to P/E is about rm25K (both price is not including the transformer,switch box,LV board etc. The reason why we do have PAT is because at that place,they did not have enough space to build P/E.That is why they need PAT to substitute the P/E.

In the evening, we all went to Bandar Utama with Abg Azrin and Abg Mad(his assistance) to do checking on the DC of the relay. During the process,I can see how the EFI function when there's a trip. This substation has relays which supported by the DC(battery-30V). They call the DC as "nadi" to the relays. When the battery or DC is not function,the relay is not working.

~ Function of relay : When trip occur,current produced was large,so the relay use a ratio to minimize the current.If the relay did not minimize the value of the current,it may cause damage to the relay and switch box.

I learn on the function of Tab Changer.It is located at the transformer and usually is set to '3' as a standard.

VCB- Vacuum Circuit Breaker
A type of circuit breaker use to protect an electrical circuit from damage caused by overload or short circuit. Its basic function is to detect a fault condition and, by interrupting continuity, to immediately discontinue electrical flow. It uses vacuum as a medium. It also contains a heater to maintain the temperature to become warm because no vapour should exist in the VCB;water can caused danger!
p/s: Only VCB uses DC to support the relay!! Oil and Gas did not use DC.

*picture of VCB-Vacuum circuit breaker*



*pictures of relays*







*picture of heater*