What control key on the fusion splicer initiates the splicing operation?

The control key that initiates the splicing operation in a fusion splicer is typically referred to as the [SET] key. This key is essential in starting the splicing process because it allows the operator to confirm that all necessary parameters and settings are correctly configured before the actual splicing occurs.

By using the [SET] key, the user may input and review important settings such as the types of fibers being spliced, splice loss estimation, and any adjustments needed based on environmental conditions. This step is crucial to ensuring a successful splice, as it prepares the machine for the fusion process and minimizes the risk of errors. Once the [SET] key has been engaged and the settings confirmed, the splicer can proceed to perform the splice operation effectively.

In contrast, other keys might serve different functions such as starting a sequence that is not directly related to initiating the splice, or executing commands that do not prepare for the splice itself. Thus, understanding the specific role of the [SET] key is crucial for any operator working with fiber optic fusion splicers.