What additional equipment is needed to display the voltage on a panel voltmeter for a high voltage power line (69 kV)?

To display the voltage on a panel voltmeter for a high voltage power line, such as one operating at 69 kV, a potential transformer is essential. This type of transformer is specifically designed to step down high voltage levels to a more manageable and safe value that can be read by standard measuring instruments, including voltmeters.

Potential transformers isolate the measuring equipment from the high voltage system, providing both safety and accuracy in voltage measurement. They allow for the high voltage to be transformed into a lower voltage, typically 120 volts or less, which can safely be handled by standard electrical meters and displays.

In contrast, current transformers are more appropriate for measuring current rather than voltage, while high voltage insulation wire is not a measurement tool but rather a component used for safely carrying high voltage power. A shunt is generally used for measuring current, not voltage. Therefore, the use of a potential transformer specifically helps to ensure that high voltages can be monitored accurately and safely on lower-voltage panels.