Sonics VC500 - Manual (Page 12)

12
USING THE ULTRASONIC PROCESSOR
The speed control on an automobile, can, to a certain extent, be compared to an
Ultrasonic Processor. The speed control is designed to maintain the vehicles rate of
travel constant. As the terrain changes, so do the power requirements. The speed
control senses these requirements, and automatically adjusts the amount of power
delivered by the engine in order to compensate for these ever changing conditions.
The greater the terrain rate of incline and greater the resistance to the movement of
the vehicle, the greater the amount of power that will be delivered by the engine to
overcome that resistance.
The Ultrasonic Processor is designed to deliver constant amplitude. As the
resistance to the movement of the probe increases, additional power will be delivered
by the power supply to ensure that the excursion at the probe tip remains constant.
Using a more powerful power supply will not deliver more power into the liquid.
Rather, it is the resistance to the movement of the probe that determines how much
power will be delivered into the sample.
The AMPLITUDE control allows the ultrasonic vibrations at the probe tip to be set
to any desired level. Although the degree of cavitation required to process the
sample can readily be determined by visual observation, the amount of power
required cannot be predetermined. A sensing network continuously monitors the
output requirements, and automatically adjusts the power to maintain the amplitude
at the preselected level. The greater the resistance to the movement of the probe due
to higher viscosity, deeper immersion of the probe into the sample, larger probe
diameter or higher pressure, the greater the amount of power that will be delivered to
the probe. Setting the AMPLITUDE control fully clockwise will not cause the
maximum power to be delivered to the sample. The maximum power that the
Ultrasonic Processor is capable of delivering will only be delivered when the
resistance to the movement of the probe is high enough to draw maximum wattage.
This phenomenon can be demonstrated as follows: depress the probe down against a
piece of wood. The greater the down pressure, and consequent greater resistance to
the movement of the probe, the greater the amount of power that will be delivered by
the power supply.