If the resistance being measured (including
"Open Circuit/ Disconnected states") is a higher
value than the selected range, the instrument's
display will flash (blink) , which indicates
"overrange" .
Gold Plated Five way
Input Jacks
The AMPTEC 620 front panel input jacks are a
gold plated variety that readily accept a number
of user connection modalities. The unit's
banana post input jacks may be unscrewed
several turns to exposed a horizontal hole thru
the gold plated post. The AMPTEC 620 user
can directly connect a bare wire thru the banana
post (horizontal hole). Once the wire is thru the
banana post hole you can hand tighten the
banana post to make a secure electrical
connection. The AMPTEC 620 front panel
input posts also accept wires with spade lugs,
and or banana jacks. The 48” long dual banana
Alligator Test Leads plug directly into the
Voltage High and Voltage low , and Current
high and Current low panel jacks. The spacing
of the AMPTEC 620 panel jacks only allows
horizontal connection of the dual banana jack
test leads to prevent mis-connection.
Calibration Access Screws
Recessed in the four feet on the bottom of the
AMPTEC 620ES you will note there are 4
screws (phillips head type) that are used for
calibration access. These screws are meant to
remain intact and should only be removed by
authorized personnel (i.e. Calibration Lab staff).
Optional Functional Test Box with built-in
milliammeter
An optional Functional Test Box (option FTB-
620ES) for the AMPTEC 620ES contains an
analog 10 mA full-scale milliammeter and a
variety of test resistors is available from
AMPTEC RESEARCH.
D-1.
General Operation
This section contains operating instructions for the
AMPTEC 620ES Explosive Safety Igniter Tester.
D-2. Front Panel Features and Operation
Main Power Switch
When the front panel power switch is in the OFF
/CHARGE position, all power is removed from
the ohmmeter measurement circuitry, and the
battery pack is connected to the rear panel
charging circuit. When the main power switch is
placed in the ON position, the unit's battery pack
is disconnected from the charging circuit. The
possibility of a common mode voltage between
the device under test and AC Power ground is
therefore completely eliminated. The operator
need not be concerned if the battery charging
adapter is plugged into the AMPTEC 620ES as it
is disconnected during any resistance
measurements.
Range Switches
model 620A-4 shown
The AMPTEC 620 series ohms ranges are selected
by pressing the desired range switch on the front
panel. The range select pushbutton for the lowest
resistance range ( leftmost resistance range button)
indicated above the range select buttons. When a
given range is selected (pushed in) the other range
switches "pop-out" and inform the user. It is
obvious to the 620 user which resistance range has
been selected, as it is the only range button pushed
in. Also note that a resistance range should be
selected after powering up the 620ES in order to
place it in an operational mode. After turn "ON", a
range should be selected. For new instrument
users with a 200 Ohm range AMPTEC Igniter
Tester, the unit will measure resistances up to 200
Ohms.
CHAPTER D - OPERATION, FUNCTIONAL
AND USE
