What it does

TamperLock mode locks the settings of a source or meter so the instrument can only be turned on and off, and a reference taken.

For example:

A source and meter can both be set "permanently" to a required λ and dB mode for loss testing.
A power meter only can be set to a required λ and dBm for transmission power testing.
A source can be set to a particular tone & λ for use with a fiber identifier.

The mode can be exited if needed, for example if it is found to be incorrect while deployed on a different job.

To prevent tampering, it's status can be tracked by a unique user PIN code.

Unique user benefits

Useful for repetitive measurements to avoid mistakes, reduce skill, and work faster
The same instruments can be set up for different applications, rather than having to buy multiple very basic instruments for each application.
Improve test traceability and quality.
Escape mechanism for when it's inappropriate.
Designed to be managed by one or more supervisors.