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

AGV-HP(O) 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 AGV-HP(O). At a minimum, the
environmental temperature must be controlled to within 0.25ºC per 24 hours to ensure the AGV-HP(O)
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 AGV-HP(O) 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 AGV-HP(O). 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 AGV-HP(O), 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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