What does the centrifugal pump switch mean?

Guys, it’s the bypass switch; I’ve been trying to figure it out for two days but still can’t understand it

The bypass switch acts as a substitute for the liquid level switch; once the bypass switch is closed, whether the liquid level switch operates or not has no impact on the result of the subsequent \"or\" operation.

Isn’t this the 0 interlock? With the bypass switch closed, there is always a 1 signal, so no interlock occurs

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This is the backend operation for the instruments, right? If the switch for shutting down the pump when the liquid level is low is bypassed, then the pump cannot be shut down automatically when the liquid level drops; however, if that switch is reconnected, the pump will be shut down automatically as a result

That’s how I understand it: the units ahead are all testing devices, and the ultimate goal is to stop the pump. Is this bypass switch a manual-operated device?

This is not the switch for switching the centrifugal pump…… This is a bypass switch for the interlock circuit, used to disable that particular interlock. For example, if you need to service that level gauge, use a bypass to disable the interlock in order to prevent it from activating.