Red Lion LEGEND - Manual (Page 8)

GENERAL DESCRIPTION (Cont’d)
Up to ten messages can be programmed. Messages can be requested by an
output status change, User Input(s), or through serial communications. The
messages can be programmed for block or character scroll, to blink, time out, and
to alternately flash between message and indication display. On dual color models
the message can be programmed to be displayed in either color. This capability is
very useful in drawing the operator’s attention to particular messages.
The program disable DIP switch, a code value, and an external User Input
selected for Program Disable can be utilized to provide multi-level protection
against unwanted changes to data values and unit configuration.
The Legend Plus features enhanced serial communications. The Serial port
can be configured for connection to RS-485 or RS-232 devices. It can be used for
data retrieval and for programming various data values.
Optional Legend Plus Programming software (SFLGP) for IBM ® compatible
PCs is available to program all of the Legend Configuration parameters, such as,
messages, count modes, etc. The software allows unit configurations to be
created, uploaded, downloaded, and saved to a file for rapid programming of the
Legend unit.
The six Programmable User Inputs can be configured to provide a variety of
functions. Four User Inputs are located on the upper rear terminal block. The
other two inputs are front panel function keys.
The LGPB offers a choice of seven programmable counting modes for use in
applications requiring bidirectional, Anti-coincidence, and Quadrature
counting. The count inhibit function can be utilized with all of these input
response modes by programming User Input 4 for the Inhibit Count function.
Input A accepts a signal for the Process, Total and Rate displays. Input B
accepts a signal for the Process display or direction control. In the
Anti-coincidence mode, both inputs are monitored simultaneously, so that no
counts are missed, and the final count can be chosen as the sum or difference of
the two inputs.
Rate, Process & Total displays have separate scaling and decimal point
placement, for readouts in different units. The Counter Load feature enables the
operator to modify the count value. This is useful when flawed material has been
counted and it is necessary to adjust the count value accordingly.
The rate operates in the time interval method (1/tau) to calculate the rate value.
This method insures high resolution at all input rates. Averaging can be
accomplished by programming the Minimum and Maximum Update Time for the
desired response. Extensive scaling capabilities allow practically any reading at
very slow input rates.
The construction of the LGPB unit is a lightweight, high impact plastic case
with a clear viewing window. The sealed front panel with the silicone rubber
keypad meets NEMA 4X/IP65 specifications for wash-down and/or dusty
environments, when properly installed. Plug-in style terminal blocks simplify
installation and wiring changes.
SAFETY SUMMARY
All safety related regulations, local codes and instructions that appear in the
manual or on equipment must be observed to ensure personal safety and to
prevent damage to either the instrument or equipment connected to it. If
equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.
Do not use this unit to directly command motors, valves, or other actuators not
equipped with safeguards. To do so, can be potentially harmful to persons or
equipment in the event of a fault to the unit.
BASIC OPERATION
The unit contains three counters that keep track of the Process Count, Batch
Count, and Total Count. The unit takes the actual number of pulses counted (internal
count value) and multiplies them by the Count Scale Factor and Count Scale
Multiplier. This results in the desired reading value for the Process Count display.
The Total Count is scaled by the same Count Scale Factor and Count Scale
Multiplier as the Process, and is additionally scaled by a Total Scale Factor. A Total
Scale factor of 1.0000 provides a total count that is scaled identically to the process
count. A Total Scale Factor of 0.0010 provides 1 total count for every 1000 process
counts. The Batch Count registers 1 count each time a process is completed.
During operation of the Legend Plus, after internal scaling is complete, any
digits remaining to the right of the least significant digit (LSD) of the display is
examined by the unit. If this digit is equal to or greater than 0.5, the LSD of the
display is rounded to the next higher digit. Any number less than 0.5 is ignored.
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