What is the difference between tan delta test and megger test?

Tan delta testing, also known as dissipation factor (PF) testing, or loss angle testing or dielectric dissipation factor(DDF) , is a diagnostic method used to measure dielectric loss/dissipation factor(tgδ) and capacitance (Cx) and evaluate the insulation condition of electrical equipment, such as cables, transformers, capacitors, and rotating machines.
What is the secondary injection test for protection relay?

The secondary injection test for protection relays is a common testing method used to evaluate the performance and functionality of protective relays in electrical systems.
What are the methods of cable testing ?

This article will talk about the methods of cable testing .The cable testing focused on insulation layer and the leakage , withstand voltage , dielectric loss and partial discharge characteristics of cable insulation
Battery Discharge Testing: A Comprehensive Guide to Testing and Ensuring Battery Health

This article introduces battery discharge testing information and the guide of battery discharge capacity test ensure to help you successfully proceed discharge testing to identify the battery state of health (SOH)