**Power Factor Correction in Welding Transformers**

The power factor correction of a welding transformer is achieved by connecting a capacitor on the primary side of the transformer. This helps in improving the power factor of the welding transformer and reduces its reactive power consumption.

**Reasons for Power Factor Correction:**

In welding transformers, the power factor is generally poor due to the presence of inductive loads. Inductive loads, such as the welding arc, cause the current to lag behind the voltage, resulting in a low power factor. A low power factor means that the reactive power drawn by the transformer is higher than the actual power required for welding. This leads to inefficient use of electrical energy and increased power consumption.

**Advantages of Power Factor Correction:**

Power factor correction in welding transformers offers several advantages, including:

1. Improved Power Factor: Connecting a capacitor on the primary side of the welding transformer helps in compensating for the reactive power drawn by the inductive load. This results in an improved power factor, which is closer to unity.

2. Reduced Reactive Power Consumption: By improving the power factor, the reactive power drawn by the welding transformer is reduced. This helps in optimizing the power usage and reduces the burden on the power supply system.

3. Cost Savings: Power factor correction can lead to significant cost savings in electricity bills. By improving the power factor, the overall power consumption is reduced, resulting in lower electricity expenses.

**Connection of Capacitor on Primary Side:**

The capacitor is connected on the primary side of the welding transformer to compensate for the reactive power drawn by the inductive load. This connection is made in parallel to the primary winding of the transformer. The capacitor is selected in such a way that it generates a leading reactive power component, which cancels out the lagging reactive power component caused by the inductive load.

By connecting the capacitor on the primary side, the reactive power drawn by the welding transformer is compensated, resulting in an improved power factor. This helps in efficient utilization of electrical energy and reduces the burden on the power supply system.

In conclusion, the capacitor is connected on the primary side of the welding transformer for power factor correction. This connection helps in improving the power factor, reducing the reactive power consumption, and optimizing the power usage in welding applications.