The single pan electronic balance works off of the theory of a double pan mechanical balance, but is a much faster and unencumbered process. The procedure, basically, consists of establishing a calibrated zero point, placing and object on the pan, and reading the mass presented on the digital display.
First, you will be familiarized with the balance controls. Discussion of the calibration and measuring cycle will then be explained. Finally, the actual massing process will be determined.
Since the average cost of an electronic, analytical balance is $2500, it is very much in your interest to learn the following procedure. Take notes! Improper usage of the balance could result in damage! Do you have an extra $2500 laying around?
If chemical is underneath the pan, you may remove the pan by lifting it, in a vertical fashion, off of its pedistal. Clean the chamber with the artist's brush and then replace the pan upon the pedistal.
Check the bubble inside the chamber to see if the balance is level. If not, adjust the leveling screw(s) until adequate. At this point, all balance doors should be closed.
Lightly press the control bar DOWN and then release. You will feel a faint 'click' when this function is performed properly. Immediately the digital mass display will show the following for a few seconds.
This display will then be automatically followed by:
and finally,
will automatically be displayed.
This cycle wil normally take place when turning on the balance. If 0.0000 is not displayed or is slow in its appearance on the digital mass display, vibrations and/or air currents have prevented a stable zero point. Elimination of these factors will immediately allow te balance to zero.
If a power interuption occurs while the balance is operating, the OFF-1 message appears on the digital mass display. If this occurs, simply press the control bar down and then release to resume normal operations.
The balance may be turned off at any time by simply pressing the control bar UP until a 'click' is felt and/or heard. The digital mass display will then go dark.
AE 50/100
The calibration mode has now been completed.
Everytime the balance is switched on, a calibration function should be performed folowing the START-UP procedure. Once calibrated, and with the balance remaining on, no further calibrations are necessary.
Possible selections for integration times are:
-1- Used for a very stable, vibration-free massing table or foundation (a short measuring cycle)
-2- Normal setting
-3- Used for unfavorable ambient conditions (a long measuring cycle).
To make your selection, simply press and hold the control bar down until the letters -Int- appear in the display.
Release the control bar.
Immediately, press the control bar down and release (click the control bar) until one of the previously discussed, selections is made.
At this point, stop and wait for the display to return to the massing mode (i.e., 0.0000). Once the display has returned to the massing modek, the stability or balance sensitivity may be selected.
Possible stability selections are:
-1- Great sensitivity (a long pause before data are released)
-2- Less sensitivity (a short pause before the data are released)-Normal setting.
-off- The stability detector is switched off (digital display may fluctuate).
To make your selection, simply press and hold the control bar down until the letters -ASd- appear in the display.
Release the control bar.
Immediately, press the control bar down and release (click the control bar) until one of the, previously discussed, selections is made.
At this point, stop and wait for the display to return to the massing mode (i.e., 0.0000). If selections 1 or 2 (from above) are made, the digital display may only be read (i.e., while massing or taring) after the stability detector lamp goes out. If selection 3 (ASd off) is made, the digital display can be read at any time. The stability degector lamp will remain off at all times while in this mode. Since this is the case, fluctuations in the mass readings are normal and the operator must decide which mass readings to accept.
To tare out the container's mass, simply place the container on the pan.
Close all balance doors.
Press the control bar down once and release.
The digital mass display will then read 0.0000.
At this point, whatever is placed inside the container will be massed directly.
To obtain the mass of a reagent, simply open the balance door(s), add the required amount of chemical to the container and then close the balance door(s).
Wait for the stability detector lamp to go dark and then read the digital mass display.
If the stability detector was switched off, then the display may be read at anytime.
i.e.
stability detector
DO NOT USE ANY STRONG SOLVENTS!
The small artist's brush may be used to remove residues from the massing chamber.