Installation of a doorbell in an apartment : Wired Doorbell
Quote from Article entitled Installation of a doorbell in an apartment:
Connection of the doorbell to the current is carried out by the connection of its contacts with the wiring of an apartment. If it is too long, they need to be cut and clean with the utility knife. Electricians recommend squeezing already connected wires accurately by pliers to make connection more reliable, and the contact better. Connections are isolated and then we checked if everything is working. If four-wire mechanism is connected to the two-wire wires, then the phase and zero are determined participating in the connection. The remaining wires are interconnected and carefully isolated.
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