Accuracy And Temperature Effects - Aerotech PRO165SLE Hardware Manual

PRO165SL/SLE

1.2. Accuracy and Temperature Effects

Aerotech products are designed for and built in a 20°C (68°F) environment. Temperature changes
could cause a decrease in performance or permanent damage to the stage. At a minimum, the
environmental temperature must be controlled to within 0.25ºC per 24 hours to ensure the stage
specifications are repeatable over an extended period of time. The severity of temperature effects
on all specifications depends on many different environmental conditions, which include how the
stage is mounted. Contact the factory for more details.
The accuracy specification of stage is measured 25 mm above the table with the stage in an
unloaded condition. The stage is assumed to be fully supported by a mounting surface meeting or
exceeding the specification in
The accuracy of the screw is a key element in the overall positioning accuracy of the SL stage. A scale
error can be expected if temperature of the screw differs from 20° C (68° F). The greater the
temperature difference, the greater the error. The temperature of the screw depends on the speed
and duty cycle of the stage. The faster the movement and higher the duty cycle, the more the stage
accuracy will be affected by heat. The thermal expansion coefficient of the screw is 11.7 ppm/°C.
SLE stages contain a linear encoder for direct feedback of the carriage position. The stage travel as
seen by the linear encoder will expand at the rate of 3.25 ppm/°C as the temperature of the encoder
scale deviates from 20°C.
The ThermoComp™ option is a hardware and software solution that uses the functionality of the
Automation1 or A3200 controller to mitigate the effects of changing temperature by detecting and
compensating for thermal changes. ThermoComp™ is effective at compensating for both self-
heating and environmental temperature changes.
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Section 2.2.
Hardware Manual
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