RoboteQ AX2550/2850 TV Converter Box User Manual


 
Connecting Sensors and Actuators to Input/Outputs
62 AX2500/2850 Motor Controller Users Manual Version 1.7. February 1, 2005
Internal Voltage Monitoring Sensors
The AX2500/2850 incorporates voltage sensors that monitor the Main Battery voltage and
the Internal 12V supply. This information is used by the controller to protect it against over-
voltage and undervoltage conditions (see Overvoltage Protection on page 32 and Und-
ervoltage Protection on page 32). These voltages can also be read from the RS232 serial
port using the ?e query.
The returned value are numbers ranging from 0 to 255. To convert these numbers into a
Voltage figure, the following formulas must be used:
Measured Main Battery Volts = 55 * Read Value / 256
Measured Internal Volts = 28.5 * Read Value / 256
Internal Heatsink Temperature Sensors
The AX2500/2850 includes temperature sensors making contact with the each of the two
Heatsink sides of the controller.
These sensors are used to automatically reduce the maximum Amps that the controller
can deliver as it overheats. However, the temperature can be read using the RS232 port
using the ?m query, or during data logging (see Analog and R/C Modes Data Logging
String Format on page 102)
The analog value that is reported will range from 0 (warmest) to 255 (coldest). Because of
the non-linear characteristics of NTC thermistors, the conversion from measured value to
temperature must be done using the correction curve below.
It should be noted that the temperature is measured inside the controller and that it may
be temporarily be different than the temperature measured outside the case.