Omega Engineering OMB-CHARTSCAN 1400, User Manual

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3-6 ChartScan User’s Manual
Calibration Memory Write Enable/Disable
ChartScan’s constants for chassis calibration and the calibration password are stored by ChartScan in Non-Volatile
RAM (NV-RAM). The password is a safety feature used to prevent unauthorized personnel from entering
calibration mode and altering the calibration constants.
As a safeguard, the calibration password and chassis calibration constants are hardware protected by use of a
Calibration Enable/Disable switch (pushbutton, or micro-switch, as described in the following notices).
Calibration mode disabled is the factory default setting. This setting should not be changed, unless you want to
change the password or chassis calibration constants.
CAUTION CAUTION CAUTION CAUTION
Ensure calibration mode is “disabled” during normal ChartScan operation. Otherwise, the
calibration password and calibration constants may become corrupt and normal operation may
be disrupted.
Standard ChartScan units have a Calibration Enable/Disable Pushbutton .
If it is necessary to change the calibration password (via the
*K
command) or to calibrate the
chassis, the calibration mode can be enabled by indenting the pushbutton. For details on
calibration, refer to Chapter 6, ChartScan Calibration.
Early production ChartScan units do not have a Calibration Enable/Disable Pushbutton . These
units enable and disable the calibration mode using micro-switch number 9 (on the DIP switch).
If it is necessary to change the calibration password (via the
*K
command) or to calibrate the
chassis, the calibration mode can be enabled by setting micro-switch 9 to the “up” (1 position).
For details on calibration, refer to Chapter 6, ChartScan Calibration.
RS-232/422 Interface Configurations
Configuring RS-232/422 Parameters
CAUTION
CAUTION CAUTION
CAUTION
The RS-232/422 interface is only to be used for serial communications. Cable length should not
exceed 50 feet (15 meters).
•
The DIP switch is only read when power is first applied to ChartScan, and for that reason
must be set before applying power to the unit.
•
RS-232 configuration is required when using a Net232 ethernet/RS-232 converter.
Note: Unless an interface option is used, ChartScan’s serial port operation will be with RS-232 electrical
characteristics. For serial port use, ChartScan’s rear panel DIP switch settings determine the baud rate, stop
bits, parity, and handshake.
Use the following steps when you desire to change RS-232/RS-422 serial port parameters. Note that there are
separate steps for early production units.