本发明涉及一种用交流电的电子音乐门铃，由普通电子门铃加整流电源、继电器及功率放大器构成。本发明不再需要电池供电。

This AC electronic music door bell is composed of general electronic door bell, rectified power supply, relay and power amplifier and does not need battery to power it.

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合上电梯供电开关，再分步控制柜内各控制回路电开关。检查所有电源电压和相序(相序继电器)是否正确。

Turn on the power switch, then turn on the switches in controller. Check phase and voltage.

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31是一个简单的螺丝端子适用于接口应用线圈低压单稳态继电器(24 V)和负荷在供电网络的电压(230 V)。

The 13.31 is a simple monostable relay with screw terminals suitable for interfacing applications where the coil is low-voltage (e. g. 24 v) and load is at the supply network voltage (230 v).

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