YOKOGAWA PH200, Инструкция по эксплуатации

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IM 12B6C2-E-H
34
7-6. Display resolution
ACCESS CODE : 04 (see §7-2)
DISPLAY : *DISP
Adjustment : (X)
Explanation:
The default setting of 1 gives an indication of
0.01 pH unit on the display which is the
maximum accuracy of the instrument when
normal industrial buffer solutions are used. In
some processes the indication of the last
digit can be suppressed to give an indication
of 0.1 pH units only. The instrument will
maintain its accuracy at the same level as
before only the indication is changed!!
Default : 1 = 0.01 pH
7-7. Signalling of fail condition
ACCESS CODE : 05 (see §7-2)
DISPLAY : *BURN
Adjustment : (X)
Explanation:
Besides an indication at the display in the
field, sometimes an indication of errors in the
control room is also necessary. This is possi-
ble by sending a special signal over the 2-
wire connection to the receiving instrument.
A singal of 22 mA is used, because it is
outside the normal analogue range of 4 to
20 mA. If at the receiving end an alarm is set
to the value represented by 22 mA, it is
obvious that the proper action can be taken
from the control room too . The signal uses
the same convention as used in thermo-
couple indication named as burn-out detec-
tion.
Default : 0 = OFF
7-8. Stabilization check
ACCESS CODE : 06 (see §7-2)
DISPLAY : *
i
T.SEC en *
i
PH
Adjustment : Criteria for automatic
calibration stabilization
time and pH.
Explanation:
The criteria for deciding whether a value has
stabilized during calibration is set to a rate of
0.02 pH during 5 seconds. Depending on
the specific needs of your sensor system
this parameter can be changed.
Please keep in mind that changing both
values will not always change the criteria i.e.
0.02 pH/5 s=0.04 pH/10 s=0.10 pH/25 s
etc. If the system has not stabilized an error
E02 will be generated.
Default : 0.02 pH/5 seconds.
X
0
0.1 pH displayed
1 0.01 pH displayed
X
0 UIT
1 AAN
22 mA steady signal on fault.
2 AAN 22 mA pulse during 30 s at start
of fault then normal output.