The analog read function works by converting a voltage in the range 0 - 5 Volts to a number in the range 0 - 1023.
So the value you get from AnalogRead depends on the voktage present on the analog pin you are reading.
so for the values you use (0 -200) it would only do anything if the voltage present on the analog pin is in the range
0 - 976 mV if the voltage exceedes 976 mV your code will not change the state of any of the digtal pins.
So basically you must know what voltage your sensor is putting out.
It is possible to change the upper voltage limit that AnalogRead is looking at, by using the AREF function. Search the forum for this, it was duíscussed in a very recent thread.
MikMo