Returns a list of 2-tuples, e.g. [(-3.14, 3.14), (-0.001, 0.001)],
            one tuple per parameter, giving min and max for that parameter.

def _getSensorLimits(self):
        """ Returns a list of 2-tuples, e.g. [(-3.14, 3.14), (-0.001, 0.001)],
            one tuple per parameter, giving min and max for that parameter.
        """
        limits = []
        limits.extend(self._getTotalDemandLimits())
#        limits.extend(self._getDemandLimits())
#        limits.extend(self._getPriceLimits())

#        limits.extend(self._getVoltageSensorLimits())

#        limits.extend(self._getVoltageMagnitudeLimits())
#        limits.extend(self._getVoltageAngleLimits())
#        limits.extend(self._getVoltageLambdaLimits())
#        limits.extend(self._getFlowLimits())

        logger.debug("Sensor limits: %s" % limits)
        return limits