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SECTION IV MANUAL OPERATION
_______________________________________________________________
4-1. General
This section of the manual contains complete instructions for manually operating the 4300B Digital Micro-
Ohmmeter.
4-2. Connections
Connections to the 4300B are made via 4 heavy-duty binding posts on the front panel. When using Valhalla
test leads, the tabbed side of each banana jack is connected to the
current
terminals (see below). This ensures
that current is carried in the largest conductor of the cable, and that the voltage input is shielded. A set of rear
mounted terminals is available as Option JB-2.
V
HI
☼
☼
I
HI
←
Tab
V
LO
☼
☼
I
LO
←
Tab
NOTE:
If the input terminals are not connected to a load (open), the display will roll around and may or may
not indicate an overrange. This is a characteristic of the voltmeter and does not indicate a fault in the
instrument.
The four-terminal configuration of the 4300B eliminates errors normally caused by test lead and contact
resistances. In many applications the contact resistance can exceed the value of the load by several orders of
magnitude. The 4300B bypasses this potential error source by providing two terminals of constant current and
an additional two terminals for high impedance voltage measurement. The result is a fast, accurate resistance
measurement of the load, independent of the resistance of the current carrying leads.
