Accuracy And Temperature Effects; Power-On Thermal Drift - Aerotech AGV3D Series Hardware Manual

AGV3D Hardware Manual

1.2. Accuracy and Temperature Effects

Aerotech products are designed for and built in a 20°C (68°F) environment. Extreme temperature
changes could cause a decrease in performance or permanent damage to the AGV3D. At a minimum, the
environmental temperature must be controlled to within 0.25ºC per 24 hours to ensure the AGV3D
specifications are repeatable over an extended period of time. The severity of temperature effects on all
specifications depends on many different environmental conditions, including how the AGV3D is
mounted. Contact the factory for more details.

1.2.1. Power-On Thermal Drift

For the best possible accuracy and repeatability, it is recommended that the +5 V feedback power supply
be connected to the galvano motors for a minimum of four hours prior to performing any critical
operations with the AGV3D. Application of the feedback power supply can raise the temperature of the
galvano motors, resulting in a transient period of "power-on" thermal drift. Allowance for this warm-up
period provides the galvano motors sufficient time to achieve thermal equilibrium.
In applications where a mark-and-measure calibration is performed to improve accuracy, it is essential
that the calibration procedure not be conducted prior to completion of the warm-up period. Otherwise,
the calibration may not be effective due to the change in zero offset that can result from the "power-on"
thermal drift.
To minimize delays in operating the AGV3D, it is recommended that the +5 V feedback power supply is
continuously maintained to the galvano motors, even when they are not under servo control.
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1.2. Accuracy and Temperature Effects
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