Computing functions – Yokogawa JUXTA MXD User Manual
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IM 77J04X12-01E
1st Edition
Aug 31,2005-00
6. COMPUTING FUNCTIONS
6.1
MXD-A Free Program
This computing unit is used to meet individual applications by pro-
gramming the available commands using a PC (VJ77 Parameters
Setting Tool) or the JHT200 Handy Terminal. Set the computing pro-
gram in G01 to G59.
6.2
MXD-L Analog Memory
This computing unit carries out the analog output (Y) of the value that
corresponds to the analog input (X) as an ordinary computing unit as
long as the contact input (DI) is ON (SHORT).
When the contact input is OFF (OPEN), the unit holds the analog out-
put at that time (Y) all the time.
6.3
MXD-M Peak Holder
This computing unit carries out the analog output (Y) of the value that
corresponds to the analog input (X) as an ordinary computing unit as
long as the contact input (DI) is ON (SHORT).
When the contact input is OFF (OPEN), the unit outputs the analog
signal (Y) that corresponds to the peak value of subsequent analog in-
put (X).
6.4
MXD-N Bottom Holder
This computing unit carries out the analog output (Y) of the value that
corresponds to the analog input (X) as an ordinary computing unit as
long as the contact input (DI) is ON (SHORT).
When the contact input is OFF (OPEN), the unit outputs the analog
signal (Y) that corresponds to the bottom value of subsequent analog
input (X).
6.5
MXD-P Program Setter
This computing unit resets the program, outputs and holds the starting
value of the time table when the contact input (DI) is ON (SHORT).
When the contact input is OFF (OPEN), the unit starts the program
and outputs the analog signal (Y) according to the time table. When
the program ends, the unit outputs the end value of time table and
holds it until the next reset command (contact input in ON (SHORT)
status) enters.
Up to 21 time tables can be set and give relationship of time vs. out-
put.
Any number (1 to 20) of line segments of time table can be set in H43.
Set a number (1 to 20) of line segments in H43.
Set X axis (time) in H01 to H21: CONST.
X axis breakpoint H01 corresponds to Y axis breakpoint H22 and
shifts orderly thereafter.
Fixed constants (H01 to H43) can be changed using the Handy Termi-
nal.
0 to 100.0% in H01 to H21 corresponds to 0 to 1000 seconds.
0 to 100.0% in H22 to H42 corresponds to 0 to 100.0% of output.
Number of line segments 1 to 20 of time table corresponds to 100 to
2000%.
●
Setting condition of time table:
0.0%
Ϲ
(H01 to H21)
Ϲ
32000% (0 to 320000 seconds)
−
6%
Ϲ
(H22 to H42)
Ϲ
106%
H01
●
Setting resolution:
Time: 1 second (0.1%)
Output: 0.1%
●
Setting accuracy of time table:
(
±
5.0% of set value)
±
1.0 second
●
Number of significant digits: 4
X axis:
t
0
to
t
20
(e.g. 123456 seconds unacceptable, 123400 sec-
onds acceptable)
Y axis: Y
0
to Y
20
(e.g. 12.34% unacceptable, 12.3%, acceptable)
6.6
MXD-Q Integrated Pulse Output
This computing unit outputs the integrated pulse according to the fol-
lowing expression.
DO = K1 · X · 10
where
DO: Integrated pulse output (pulse/hour)
X: Input signal (%)
K1: Integration factor (no unit)
Pulse output is ON pulse of 100 ms. However, the maximum number
of output pulse is 5 pulses / second. Also, the analog signal is always
output as monitor of input signal (X).
Integration factor (K1) can be set in H01: CONST.
Fixed constant H01 can be changed using the Handy Terminal.
●
Setting range of integration factor:
0.01 to 18 (1% to 1800%)
Number of significant digits: 4
Minimum unit: 0.00001
●
Computation accuracy:
1000
±
2 (pulse/hour) (However, when K1 = 1, X = 100%.)
●
Specification of contact output:
Maximum permissible load: 30 V DC/200 mA
●
Number of significant digits: 4
(e.g. 1.23456 unacceptable; 12.34, 1.234, 0.01234 acceptable)