Transformer Turns Ratio & Winding Resistance Tester

In transformer manufacturing, DC resistance or turns ratio measurements are required during semi-finished and finished product factory tests, installation, overhauls, tap changer modifications, commissioning tests, and preventative tests by the power sector. These measurements can also check the welding quality of winding joints and for inter-turn short circuits, verify the contact quality of each position of the voltage tap changer, confirm the correspondence between the actual and indicated tap changer positions, check for broken leads, and inspect multi-strand wires for broken strands. Traditional testing requires multiple connection intervals using two instruments, which is time-consuming, inefficient, and severely impacts production schedules.
To meet the need for rapid measurement of transformer DC resistance and turns ratio, our company has developed the MOEORW- W 4670Q Transformer DC Resistance and Turns Ratio Comprehensive Tester . This instrument uses a one-time wiring connection and can complete turns ratio testing and DC resistance testing of all six phases (high and low) without disconnecting the wiring. These functions can be achieved simply through touchscreen operation.

Key Specifications of DC Resistance:

Key indicators of transformer ratio:

Characteristics of DC resistance function

• This product is suitable for testing inductive loads such as 10 kV and 35 kV distribution transformers, instrument transformers, motors, and generators, as well as measuring wires, relay switch contacts, etc.
• It has a temperature conversion function, which can convert the resistance value to different temperatures according to customer needs, making it easy to compare data.
• It has protection functions such as discharge sound alarm, power overheating, and reverse voltage connection.
• The on-load switch can be switched directly in the measurement state, and the instrument will automatically refresh the data without the need for a reset operation.
• It has 6 current levels and an automatic current level selection function, which can automatically select the current level according to the load.
   

Transformer Ratio Functional Characteristics

• The instrument uses a three-phase precision inverter power supply, which eliminates the harmonic effects of the mains voltage during measurement, resulting in more accurate measurements. There is no impact when the working power supply is a generator.
• It adopts three-phase output voltage to improve the testing speed. It can measure the phase angle and automatically identify the wiring group 0-11. For rectifier transformers with multiple windings under low voltage, the turns ratio and 7.5° angle deviation can be measured without disconnecting the low voltage side.
• It is applicable to a wide range of transformer types, especially suitable for measuring Z-type transformers, rectifier transformers, grounding transformers, electric furnace transformers, etc.
• It features high and low voltage reverse connection protection, transformer inter-turn short circuit protection, tap changer incomplete opening/closing protection, and output full short circuit protection, increasing instrument stability.
• After inputting the rated parameters, it can automatically measure the transformer turns ratio, error value, and tap position. Especially for taps with asymmetrical taps, it can accurately measure the exact position of the transformer taps. It can measure up to 99 tap positions.
• Seven-inch high-brightness touchscreen color LCD, clear display even in strong light, full touchscreen operation, and free switching between Chinese and English.