Unless or otherwise specified the transformers will be connected as per Vector Group reference DYn 11 in accordance with International practice.
The core used is best quality cold rolled gain oriented and laser processed silicon steel sheet. They provide low iron loss,low noise, compact size and have the best performance for high efficiency transformers.
We use high quality conductor of copper/aluminium in our products. Round or rectangular copper/aluminium wires/strips ribbed with thermally upgraded insulating paper are applied in oil immersed transformers. The winding have a compact size,excellent heat transmission, low load loss, high lighting impulse resistivity and outstanding anti-short-circuit strength.

On load tap changer (OLTC) is used with higher capacity transformers where HT side voltage variation is frequent and a nearly constant LT voltage is required. OLTC is coupled with the transformer itself. Multiple tapings from HV windings are brought to the OLTC chamber and connected to fixed contacts. Moving contacts rotates with the help of rotating mechanism usually a Geneva mechanism having a spindle. The spindle can be rotated manually as well as electrically with a motor. Motor is connected in such a way that it can rotate in both the directions such as to rotate the OLTC moving contacts clockwise and anti clockwise. Two push buttons are fitted on the LCP (lowcontrol panel) to rotate the motor and hence the OLTC contacts. This movement of contacts thus controls the output LV voltage of the transformer. So rotating of the OLTC contacts with spindle or push button in this way is manual process. In case this process of rotating the OLTC contacts and hence controlling the LV side voltage is to be done automatically then a RTCC (remote tap changer controller) is installed with the transformer ht panel. The RTCC panel which has sensors which sense the output voltage and accordingly sends signal to LCP and LCP in turns rotates the motor as per signal received from the RTCC.

An intrinsic byproduct of the transformation process is heat, specifically, the “I2R” (I=Current, R=Resistance) heating that occurs when current runs through a conductive wire. Heat breaks down transformer composition materials and insulation, resulting in less efficiency and shorter service life. Transformer heat is best controlled by the oil filled transformers, which conducts the heat away from the heat-producing parts while protecting other internal transformer workings.

Inspite of the best efforts by all the state electricity boards across the country , the voltage received at the end user is never constant. This erratic power supply is the main cause of breakdown of electrical equipment. Voltage varies in a fashion that generally it is low during day time and high during night hours. Moreover on the holidays, peak hours, rainy days and when agriculture load is switched off, the voltage rises sharply which is more dangerous. In India all the electrical equipment are rated at 400 / 415 Volts three phase and 220 / 230 Volts single phase

GTB’s Compact Substation is used for feeding power form high voltage to low voltage in open cast mines, construction sites, metro cities etc. The substation is compact in size, suitable for frequent shifting and for use in indoor / outdoor locations. The substation is installed and mounted on skid frame or wheels or channels and is provided with lifting hooks

We are the leading manufacturers and suppliers of isolation transformers like ultra isolation transformers, power isolation transformers, super isolation transformers, which protect the Isolating sensitive equipment from Line Voltage transients, spikes & D.C Leakage etc. These ultra isolation transformers are specially designed for sensitive critical equipment like industrial, computers & peripherals, medical instrumentation, digital communication telemetry systems, CNC Machines etc. and stopping such disturbances generated by the noisy equipment load from being injected into the power line.