When measuring winding resistance, which tool provides an accurate reading directly in ohms?

The tool that provides an accurate reading of winding resistance directly in ohms is the transformer ohmmeter. This device is specifically designed to measure the winding resistance of transformers and other electrical equipment reliably. It applies a known current through the windings and measures the resultant voltage drop, allowing it to calculate the resistance using Ohm's law.

The significance of using a transformer ohmmeter lies in its capability to handle the specific characteristics and requirements of transformer windings, such as the low resistance values involved. It provides precise measurements that are crucial for assessing the health and condition of the windings, which is essential for ensuring efficient operation and preventing overheating or failure.

In contrast, the digital multimeter can measure resistance but may not provide the same level of accuracy or be suitable for the low resistance values typically found in transformer windings without additional considerations. A clamp meter is generally used for measuring current and is not equipped to measure resistance directly. The insulation resistance tester is primarily used to measure insulation resistance, which is different from winding resistance and does not provide readings in ohms for winding purposes.