The Feng Shui compass, also known as a Lo Pan, is an indispensable tool for the Feng Shui consultant.
The Feng Shui compass is nothing more than a compass with Feng Shui formulas embedded into concentric rings on a metal plate known as the heaven dial. In most versions, it sits on a wooden base known as the earth plate.
The Feng Shui compass does not point to north like its western counterpart. Instead it sticks to Chinese mapping convention and point south. You may be interested to know that the direct translation for a compass in Chinese is “Pointing South Needle”.
Feng Shui Compass Type
The Chinese Feng Shui compass can be classified into three types. They are the San He, San Yuan and Chong He compass. The San He compass incorporate many formulas from the San He or Three Harmony schools while the San Yuan incorporate many formula from the San Yuan or Three Cycles schools. Flying Star Feng Shui is an example of a system from the San Yuan schools.
The Chong He compass is a combination compass that includes some formulas from both the San He and San Yuan schools. All three compasses have some formula rings in common. They include the 24 mountains, early and later heaven arrangement.
The Feng Shui compass can also be made to order. I have seen one that incorporates the Gua numbers and directions from the Eight Mansions School.
Some masters also make their own compass and they incorporate formulas that are used by their school only. Some masters also add their own spin into their compass. For example I have seen one that incorporates the flying star chart for the current and previous period. With it, you can take the measurement and read the flying star chart off the Feng Shui compass.
No need to refer to formula book or draw the chart manually!
Reference:http://www.absolutelyfengshui.com/fengshui/chinese-feng-shui-compass.php,Absolutely Feng Shui