It is the target of remote maintenance that the dispatch control center can dial and transfer parameters to RTU in substation.

远程维护是为了使调度控制中心可以实现对变电站内rtu的远程拨号、参数下传等维护功能。

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The 4 o'clock spot is a Master button (for saving settings and quickly returning the center dial to its main volume control), and 6 o'clock features a half-dozen blocks that correspond to your virtual surround speakers.

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