VersaMax, SpectraMax 340PC384, 190, Plus 384 Microplate Readers User Guide
11
0112-0126 B
The guidelines for cuvette use in the instrument are the same as those that apply to any
high-quality spectrophotometer. You must ensure that the meniscus is comfortably above
the light beam in standard cuvettes and that the sample chamber in a microcuvette is
aligned properly with the beam. The light beam is 0.625 in (15.87 mm) above the cuvette
bottom.
The instrument can accommodate standard-height (45 mm), 1-cm cuvettes and 12 x 75 mm
test tubes when used with the test tube cover. The instrument does not accept short (25
mm high) microcuvettes. See
.
Not all manufacturers’ cuvettes are the same with regard to design, materials, or
configuration. Temperature uniformity within the cuvette may vary depending on the type
of cuvette you use.
Temperature Regulation
The instrument contains an incubator that enables you to control the temperature in the
plate chamber for Endpoint read type protocols. When you power on the instrument the
incubator is off. The temperature in the plate chamber is ambient and isothermal.
The instrument is designed to regulate the temperature of the plate chamber from 4°C
above ambient to 45°C. The instrument control panel and the SoftMax Pro Software enable
you to turn the incubator on and off to adjust the plate chamber temperature. The
temperature set point defaults to 37.0°C at start-up.
The instrument control panel displays the temperature in the plate chamber except for the
SpectraMax Plus 384 where the instrument control panel displays the cuvette chamber
temperature. Use the SoftMax Pro Software to view the plate chamber temperature for the
SpectraMax Plus 384.
Typically, the plate chamber reaches 37.0°C in less than 30 minutes. The plate chamber
temperature is maintained at the set point until you to turn temperature regulation off.
Temperature regulation and control of the plate chamber is achieved through electric
heaters, a fan, efficient insulation, and temperature sensors. The heaters are located in the
plate chamber, which is insulated to maintain the temperature set point. The sensors are
mounted inside the chamber and measure the air temperature.
Accuracy of the temperature set point is guaranteed only if the set point is at least 4°C above
ambient. If the temperature set point is lower than the ambient temperature, the chamber
temperature remains at ambient. Temperature regulation is controlled by heaters only and,
therefore, cannot cool the temperature to a setting lower than ambient. Additionally, the
highest setting (45°C) can be achieved only if the ambient temperature is greater than 20°C.
Should you turn the incubator back on after a momentary shutdown, allow about ten
minutes for the control algorithm to fully stabilize the plate chamber temperature.
The temperature feedback closed-loop control algorithms measure the chamber air
temperature, compare it to the temperature set point, and use the difference to calculate
the regulation of the heating cycles. This technique results in accurate, precise control of the
chamber temperature with a temperature variation of the air inside the chamber of less than
1.0°C. The temperature uniformity within the plate depends on its design and composition.
