Built-in dc static eliminator – A&D Weighing BM-20 User Manual
Page 27
BM series
25
6.5.
Built-in DC Static Eliminator
(Neutralization Device)
The
BM series is equipped with four DC static eliminator electrode units to neutralize static
electricity from a charged weighing sample.
When neutralizing static electricity before weighing, stability can be improved, reducing error.
Neutralizing ion : The discharge electrodes of the built-in DC static eliminator continuously
generate bipolar ions by corona discharge. Applying these ions to the weighing
sample neutralizes the static charge.
Static
electricity
: In
general,
when the ambient humidity is less than 45%RH, powders, paper,
plastic, nonconductors, etc., easily become charged with static electricity. The
influence of the static electricity may cause a weighing error of several
milligrams. The static eliminator effectively neutralizes the electrical charge.
Operation
1 Place the sample to be weighed on the center
(of the metallic circle) of the separation plate to
neutralize the static charge.
2 Press
the
ION
key to start the neutralization.
The
mark and the LED flash.
The neutralization will stop after the preset time
of "Neutralizing time (ion)" in the function table
(the factory setting is 3 seconds).
The minimum display of
BM-20, BM-22 and BM-252 is
switched to 0.1 mg while performing the neutralization.
When pressing the
ION
key during the neutralization,
the neutralization stops.
Note
Keep a space between electrodes and the weighing sample.
Placing the sample to close to an electrode may cause the
sample to become charged.
Remove any obstacle between electrodes and the weighing sample.
Maintenance Of The Electrode Unit
In general, when using the eliminator for a long time, dust and
stains may stick to the electrodes. Clean them periodically to
maintain performance.
When pins of the electrode are rubbed down and the
neutralization function does not recover after cleaning them,
replace the electrodes with four new units. The standard life
time is approximately 10000 hours.
Replacing Electrode Unit
1 Turn the electrode unit 45 degrees counterclockwise. Remove it.
2 Replace all four units with new ones at the same time.
Note
Do not remove and clean the electrodes while the
mark and the LED are flashing.
Static eliminator
LED
Sample
Separation plate
Key
In the neutralization
Weighing display
Example: Display of
BM-20,
BM-22, BM-252
Electrode unit
Step 1
Step 2
Cleaning
Electrode