Xylem WTW DIQ/S 281, Руководство по эксплуатации

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Outputs DIQ/S 281
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6.6.4 Limit indicator
Function The characteristic of the limit indicator is laid down in the
Limit value UL
,
Limit
value LL
,
Hysteresis UL
and
Hysteresis LL
settings. The fundamentals of the
function are described in the introductory chapter (see section 6.2.2).
In order to set up the
Limit indicator
function for a relay output, the relay output
must be linked with a sensor (see section 6.4).
Settings
6.6.5
Frequency controller
Function The characteristic of the frequency output is laid down in the
Start value
,
End
value
,
Frequency (f) min.
and
Frequency (f) max.
settings. The fundamentals of
Setting Selection/Values Explanation
Limit values UL main variable
LL main variable
UL adjoining var.
LL adjoining var.
Main variable
designates the
actual measured parameter of
the sensor (e.g. pH, oxygen,
etc.).
Adjoining variable
designates
an additional measured
parameter (e.g. temperature).
Limit value UL
Upper or lower limiting
value
Any value within the
measuring range
(sensor-dependent) Minimum difference between
the upper and lower limit
value:
5 % of the measuring range
Limit value LL
Hysteresis UL
0 - 5% of the
measuring range Hysteresis for
Limit value UL
and
Limit value LL
.
Hysteresis LL
Behavior at error Open
Close
Unchanged
The relay opens, closes or
remains unchanged in the
case of system errors or
sensor errors (see page 112).
Action Open
Close
Relay action (see
section 6.6.1)
Switching delay
0 ... 3600 s The time period for which a
limiting value must be
exceeded before the relay
operates.
Prevents frequent switching
for measured values that are
close to the limiting value.