012-07124B
Basic Electrometer
$
Note:
This instruction sheet assumes the
user is familiar with
ScienceWorkshop®
or
DataStudio™. Users can gain familiarity by
working through the tutorials provided in
ScienceWorkshop
or DataStudio’s Online
Help.
The exclamation point within an equilateral
triangle is intended to alert the user of
important operating and safety instructions
that will help prevent damage to the
equipment or injury to the user.
If it is not convenient to hook the electrometer
across a known resistance in the circuit, a precision
resistor can be connected between the input leads
of the electrometer. The circuit can be broken, as
for connection to a standard ammeter, and
connected in series with the precision resistor.
Again, measure the voltage across this resistor and
calculate the current. (The problem with this
technique is that the resistance must be high
enough to measure a voltage drop, but low enough
so it doesn’t significantly affect the current through
the circuit).
Using a Computer with Science Workshop
Interface
The signal output connector on the ES-9078
Electrometer provides an output signal for the Science
Workshop interface. This provides an output
signal for displaying data in analog meters, tables,
graphs or oscilloscopes, making data analysis easy.
It is important to remember that the signal output on
the ES-9078 has a fixed scale of ±100 volts. Changing
the range switch on the electrometer has no effect on
this scaling. By choosing the Electrometer icon in
DataStudio
™
or
ScienceWorkshop®
, displays are
shown correctly scaled.
Because of limited resolution on this output, it may be
useful to apply gain within the ScienceWorkshop
interface to measure voltages of 10 volts or less.
Specifications
ES-9078 Basic Electrometer:
V
oltage input ranges:
3, 10, 30, 100 volts full scale
Input resistance:
approximately 10^14 ohms
Input capacitance:
approximately 27 pF
Accuracy:
Analog Meter:
+/
-
3%
ScienceWorkshop output:
+/
-
1%
Signal output: Fixed at -100 to + 100 volt range
(Automatically scaled in DataStudio
and
ScienceWorkshop)
Batteries:
4 - “AA” (Alkaline recommended)
Battery life:
approximately 75 hours
