BEKA BA654D, Руководство пользователя

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5.6 RATE SETTINGS
See Fig. 11
5.6.1 Rate Scaling (For pulse inputs)
The Rate Scaling factor, which may be
adjusted between 0.001 and 999999, defines
the arithmetic relationship between the units of
measurement of the batch display and the rate
display units of measurement.
Rate Scaling Factor = Units of rate display
Units of batch display
When calculating the Rate Scaling Factor, the
required units of measurement for the rate
display must be converted to those used for
the batch display as shown in the following
example.
The BA654D batch display is in UK gallons but
the rate display is required in litres.
Rate Scaling Factor = Units of rate display
Units of batch display
= 1 litre
1 gallon
= 1 litre
4.5461 litres
Rate Scaling Factor = 0.21997
If the rate display is required in the same units
as the batch display, the Rate Scaling Factor
should be set to 1.0
000001.
Set Scale Factor
5.6.2 Rate D.P. (For pulse inputs)
The position of the rate display decimal point,
which determines the resolution of the display,
is set by this function. In operation leading
zeros are suppressed
00000.0
Set Display D.P.
5.6.3 20mA Display (For 4/20mA input)
The rate display at 20mA is set with this
function. The range of adjustment is between
0.00001 and 999999
00100.0
Set 20mA Display
The display may represent flow per second,
per minute or per hour. The units of time are
defined by the Timebase, which determines
how the measured rate is integrated to
produce the batch display. See 5.6.5
5.6.4 Rate Legend
This function enables the units of the rate
display to be entered. Up to six upper and
lower case alphanumeric characters may be
used. Some of the operator screens will
display this legend against the rate display.
XXXXXX
Set Rate Legend
5.6.5 Timebase
The exact function of the timebase depends
upon whether the batch controller is
conditioned to receive a pulse input or a
4/20mA analogue input.
Pulse inputs
Number of pulses received is proportional
to volume dispensed.
The timebase multiplies the rate display by
60 if flow per minute is to be shown and by
3,600 if flow per hour is to be shown.
4/20mA Analogue input
Amplitude of the input current is
proportional to rate of dispensing (flow).
The timebase does not affect the rate
display. If the rate display represents flow
per minute, the batch display is divided by
60, if the rate display represents flow per
hour the batch display is divided by 3,600.
/Second
/Minute
/Hour
Set Rate TimeBase
Highlight the required option and press E to
enter the selection.