Quantum 9700 Metal Detector User Manual


 
3 OPERATING INSTRUCTIONS
This chapter presents detailed instructions on the operation of the 9700.
Overview
The 9700 provides digitally controlled, single shot, current pulses. The current is
provided by a 3700mF capacitor bank charged to approximately 44V. The ability of
the instrument to maintain the requested current will be load dependent, limited by
the voltage and the stored energy. Thus the output pulse is energy limited by the
amount of energy stored on the capacitor bank (CV
2
/2 = 36.2 Joules). Long pulses or
large loads will result in droop at the end of the pulse as the capacitor bank
discharges. The table below shows the maximum droop free pulsewidth as a function
of resistance and current.
----30086010
--904259905
501605001,0602
751905251,0901
10521RESISTANCE (ohms)
CURRENT (A)
MAXIMUM CONSTANT CURRENT PULSEWIDTH (ms)*
The current in the Model 9700 is controlled by a high-side power mosfet. Care
should be taken when making connections. A switch is provided for each channel to
disconnect the load from the capacitor bank.
The 9700 uses a single-line LCD to display menu selections. The front panel keys
are used to “navigate” through sets of menus to set various options and control the
current pulse generator. Some keys are only active at certain times or have different
behavior depending on what state the menus are in -- once understood, the menus can
be quickly and easily manipulated. The 9700 also contains non-volatile memory for
storing up to twelve (12) configurations, so you need not go through the entire setup
process each time the instrument is used.
9