OLTC Service | Core Power

TRANSFORMER TAP CHANGER REPAIR, MAINTENANCE AND OVERHAULING SERVICE

Tap-changers are very important components in transformers and the power grid. As they are of mechanical construction, they cause concern due to their maintenance needs and their failure probability. It is therefore important to be able to assure the integrity of tap-changers as cost effective and reliably as possible.

So, CORE POWER Serves You:

Maintenance of On-load & Off load tap changers.

Overhauling of In-Tank & Flange mounted OLTCs.

Diverter switch repair and overhauling.

Selector switch repair and overhauling

Motor drive panel overhauling and rewiring.

Conversion from Off circuit tap changer to On-load tap changer.

Supply of all critical spares for OLTC.

Fault diagnosis & solutions.

Why You Need Service on Time?

During operation arcing at diverter switch contacts results in carbonisation of oil in the diverter switch tank and wear and tear of the mechanical parts of the diverter switch.

To ensure normal operation of OLTC diverter switch should be regularly inspected overhauled and repaired.

The carbonised oil should be replaced with new oil or need of oil filtration after checking BDV of oil.

What is OLTC?

On-Load Tap Changer

The on-load tap changer is used to change the tapping connection of the transformer winding to change the voltage ratio while the transformer is still in service without interrupting the load.

How OLTC Works?

OLTC comprises two major components, the tap selector and diverter switch. The tap selector selects the tapping and its electrical contact are designed to carry the rated current of the transformer but not to make or break this current. The diverter switch, however, needs to be designed to carry, make and break the load current in circuits previously selected by the tap selector switch. During the operation of diverter switch the transition resistors bridge the tap in use and the tap next to be used, thereby limiting the circulating current due to the inter-tap voltage.

The OLTC motor drive mechanism is used to control the OLTC to increase the tap operation or decrease tap, it consists of motor, reduction gear box, planetary gear box and motor drive panel.