Identifying the Sensor
When two or more sensors are connected, the sensors can be identified by tapping or clicking Identify
in Sensor Information.
Using the Product
Connect the low leakage BNC/alligator clip cable to the BNC connector on the sensor body. Prepare the
sensor for data collection following the steps in the Getting Started section of this user manual.
General Tips
When the sensor is stored, it is a good idea to clip together the wires in order to protect the
sensor from high static potential that could damage the unit. Press the Reset button (Q = 0) with
the red and black wires connected to a common conductor for a few seconds to zero the sensor.
Pressing and releasing the Reset button with the clips connected to a voltage source, such as a
power supply or battery, will cause an error in the reading and is not recommended, because it
will short the power supply as well.
Since the sensor is capable of measuring very small amounts of charge, it is essential to begin
experiments by zeroing the sensor.
You must be careful when handling the leads or you may alter the readings with stray charge. The
insulator on the clip lead quickly becomes oily from handling, and fingers often carry small
amounts of charge at high potential that can easily leak through the insulator and affect your
reading. The best way to minimize this is by grounding your fingers, or wearing a grounding strap
on your wrist, to remove any charge before releasing the positive (red) wire from its ground
connection. Start recording data before removing the lead from ground so you will be aware if
any stray charge accumulates before making your connection. When connecting to static sources
(not a fixed voltage like a battery), the Reset button can be used while connected to a passive
charge receptor. Make sure the output reads zero after reset. If it does not, re-connect the clips to
a common conductor and re-zero the sensor.
The sensor is not differential; therefore the negative (black) side is always at ground potential.
The supplied cable is shielded and has a low leakage dielectric. When using other cables, the unit
should be tested to make sure the cable does not allow excessive leakage currents.
The negative (black) wire is the ground connection. The effects of stray static charges will be
minimized by connecting the black lead to a metal ground plane below your experiment, such as
a sheet of aluminum foil or a baking pan.
Synthetic clothing can carry significant charge, as can the experimenter’s body. Grounding the
experimenter by using a ground strap on one wrist will help. Wearing all cotton clothing can also
help.
When not using a Faraday Pail and ground plane, it helps to connect a metal cup to the positive
(red) wire. This cup adds negligible capacitance to the system, but makes it easy to see induced
or deposited charges. Insulate the cup from the ground plane using a glass jar or beaker. Plastic
does not work well because it will accumulate stray charge quickly.
Complete all experiments quickly. Due to leakage currents in the cable and apparatus, the
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