Difference between Rasi chart and BavaChalit chart

According to vedic astrology bhavchalit chart has to be studied along with Rasi chart. Rasi lagna chart predicts the personality of a person observed or behaved in common where as in bhavchalit chart denotes the unexpected behavior aspects of a person. Rasi chart has all the 12 houses equal to 0 to 30 degrees in length. Rasi chart is the main chart which explains about the sign of planets and ascendant. Rasi chart is used for understanding the planets whereas bhavchalit chart is used for understanding the houses. Most of the time planets are positioned in the same house in rasi and bhavchalit chart. However if planets change position in bhavchalit chart, astrologers should predict based on the principles of bhavchalit chart. Bhavchalit chart is used for predicting the house results where as signs in Rasi chart are used for transit analysis and tallying divisional charts.
    In case planets shift in the bhavchalit chart the dasa predictions can be implemented based on the planetary position in the bhavchalit chart. It is used for predicting the house results. Bhavchalit chart determines the dasa prediction based on the planet's effect placed in a particular house.
Sarvashtak varga SAV and bhinnashtak varga BAV use the house (bhav) of each planet rather than rasi. Aspect of planets, conjunction, debilitation and exaltation of planets and yogas are analyzed from rasi chart. Manglik dosha is partly studied from bhavchalit chart and partly from rasi chart.
    For example if venus is exalted in rasi chart in meena rasi and  in bhavchalit chart venus is moved on to mesha rasi, the native will be partially benefitted with exaltation effect.