YOKOGAWA Vigilant Plant EXA TB Series, Руководство пользователя

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<6. PROCEDURES FOR CONVERTER OPERATION>
6-20
IM 12E04A02-02E
8. Determine the position of the decimal point => H000.0 mg/l
using the [>] key.
Every time the [>] key is pressed, the decimal
point moves to the right one digit and when it
reaches the least signi fi cant digit, it returns to
the most signi fi cant digit.
9. Press the [ENT] key. => H000.0 mg/l
The most signi fi cant digit fl ashes and
waits for the numerical value entry.
10. Select a digit and set the desired upper limit => H020.0 mg/l
using the [^] or [v] key.
Every time the [>] key is pressed, the decimal
point moves to the right one digit and when it
reaches the least signi fi cant digit, it returns to
the most signi fi cant digit.
11. By pressing the [ENT] key, the upper and lower => H020.0 mg/l
limits are entered. The entire display fl ashes once.
12. When the [ENT] key is pressed, the procedure => L05.00 mg/l
returns to 1.
In operation of step 6 or 11, if the upper and lower limits are beyond the permissible range (0 to
2000 mg/l), "not" is displayed. In this case, reset the message by pressing the [>] key and repeat
the operations from step 2.
Also in step 11, if the span between the upper and lower limits does not meet the following
conditions when checked, "not" is displayed. Reset the message by pressing the [>] key in a
similar manner and repeat the operations from step 2.
Range span (Upper limit - lower limit)
≥
20 % of the upper limit
≥
2.00 mg/l
If the upper and lower limits are only to be con fi rmed, pressing the [ENT] key alternately displays
L and H.
If the auto-range switching function is to be used, set the ranges as shown below.
• Set 0.00 mg/l for all lower limits (L).
• Set the upper limits (H) in the following manner.
Range
1
≤
Rang 2
≤
Range 3
• If two-range operation is required, set Range 2 = Range 3.
• If one-range operation is required, set Range 1 = Range 2 = Range 3.
(2) Setting Averaging Coef fi cient (time constant) (FUNCTION "4")
The converter display and analog output are computed for average by the program. In this
setting, the extent of averaging (signal time constant) can be changed. Table 6.9 shows an
approximate correspondence between the averaging coef fi cient and a 90 % response time.
The 90 % response time is about the averaging coef fi cient x0.75 seconds. This coef fi cient is
set at 30 (about 22 seconds for a 90 % response time) upon shipment from the factory. If the
fl uctuation of measured readings is large, e.g., due to suspended matter in the measurement
object, change the averaging coef fi cient as necessary.
3rd Edition : May. 31, 2010-00