Before being used for checking insulators’ ability of resisting electricity, devices like super megohmmeter go through a high-level testing. The device should be perfect before it measures the capability of any other device. Resistance is connected across the terminals and then measured by this device. After calculating the capability, insulators could be created and then used for different purposes.
Buying these devices can be a tricky affair because many sellers claim to be the best. However, after judging thoroughly, a decision could be taken to choose a particular seller. Singapore-based Hioki is one of the reputed sellers of devices like megohmmeters.