Products Catalog

Specification

Display
The user can configure the Tracker 240 series for the required engineering
units and display resolution. The resolution is user configurable for 1, 2, 5.
and 10 digits. This can be useful if a steady reading is difficult to achieve.
Normally the full resolution would be displayed. For noisy signals an
independent display filter is provided. The user can select the display
update rate to be 2, 4 or 10 per second, and the brightness can be adjusted
to suit ambient lighting conditions.
Calibration Scaling and User Linearisation
Calibrating the Tracker 240 series to load cells can be achieved in one of
two ways. Values from the strain gauge can be entered manually or the
Tracker can read the actual output from the transducer at two points in
the range, normally at zero and another point near the maximum load to
be measured. These measured values are stored with their associated
display values as the calibration parameters. For more demanding
applications, up to 8 points can be independently calibrated to
compensate for transducer non linearity.
Analogue Output
The user programmable analogue output allows the Tracker 240 series to
transmit the measured display value or the Maximum, Minimum,
Average, or a value sent via the serial interface. The analogue output
can be scaled for any portion of the display range and is configurable for
4-20mA, 0-20mA or 0-10 Volt signals. Electrical isolation ensures that
problems with earth loops are avoided.
Serial Communications
The Tracker 240 series are equipped with an isolated RS422/ 485 serial
communications interface to allow connection to computers or PLCs.
Three protocols are provided as standard to allow easy integration with
most SCADA packages. The user can select  Master Mode to allow
digital transmission to a remote  Repeater display or printer. RS232 can
be supplied instead of RS422 / 485 - consult your supplier.
Sensor Connections
The Tracker 240 series use a 6-wire ratiometeric method of
measurement. Up to four 300 ohm load cells can be connected in
parallel. More can be used if the resistance is higher ( e.g. 8 x 600
ohm load cells) and the total current does not exceed 120mA at
10Vdc. An external 10Vdc supply can be used, if required, still
retaining the ratiometric measurement capability. Normally the
transducer connections would be wired as shown.
Digital Status ( Logic) Inputs
Two logic inputs are provided to allow remote control of the indicator
functions via external devices such as switches or PLCs. The inputs may
be activated by volt free contacts or open collector TTL outputs. The two
inputs can be individually programmed by a user to perform one or more of
the following functions: -
Tare
Zero
Part Count
Display Hold
Display Maximum ( Peak)
Display Minimum ( Valley)
Display Average
Display Reset ( Peak Picking Mode)
Display Test ( Lights all Display Segments)
Keyboard Lock
Alarm ( Latch) Reset
Alarm Disable
Analogue Output Hold
Reset Max, Min and Average
Start Fill
Front Panel Function Keys
The five front panel buttons can be used to set