Bio-Rad Model 680 Microplate Reader Accessories User Manual
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4.2 Functions
Overview
4.2.1 Calculations
The Microplate Reader uses Beer's Law to calculate the absorbance value of each well.
Beer's Law states that absorbance is equal to the log10 of the ratio of the baseline
measurement intensity (Io) to the sample measurement intensity (I).
Beer's Law
Absorbance = Log10 (Io/I)
Before measuring the plate, the reader takes a reading for all eight photodiode channels.
These values are recorded as the baseline measurement (Io) values for each channel,
respectively. The reader then records the sample measurement (I) value for each well, and
calculates the absorbance using these values. Channel-to-channel error is significantly
reduced because the Io value for a given channel is used only in determining the absorbance
of the wells of that channel.
4.2.2 Security
password
The Model 680 Microplate Reader requires user login with password. This security feature
helps to prevent any unwarranted modifications to the analysis conditions/protocols and data
stored in the instrument, and identifies operator on reports. The reader has two user settings,
the Administrator and the Common user. Each user level has its own security password.
4.2.3 Memory
Back-up
The battery back-up provides memory even after the reader is turned off.
The following information will be saved in the memory until new reading parameters are set
by the user or a new plate is read by the instrument. Note that if a
run is aborted before it is
finished, all the previous plate reading data remain in memory and none of the data from the
aborted reading is stored.
1.
10 latest plate reading result for End-point protocol
2. 2 latest sets of Kinetic plate reading result (Max 30 series of readings for each
Kinetic)
3.
64 End-point Protocol settings and 2 Kinetic Protocol settings
4. A set of Checkmark reference data and one latest set of Checkmark reading
result
5.
5 set of Standard curve data for the storage of standard curves and graphs
6.
8 wavelength values for filters
7. Laboratory
name
8.
Two security passwords (for the Administrator and the Common user)
9.
External printer type (ASCII or ESC/P type)
In addition to the battery back-up memory, the instrument has a small amount of none volatile
memory to keep the system information after the battery is dead. The Serial Number is stored