Toshiba Density (Consistency) Meter LQ500, Operation Manual

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6.3.2 Verifying and setting measurement conditions
(1) Verifications and settings for initial powering-ON
In the event of starting the operation after turning on the power for the first time since installing this
density meter, it is necessary to first set the measurement conditions of the converter. Various
measurement conditions (parameters) are verified and set by means of the setting key while
viewing each menu screen of the LCD indicator. Major measurement conditions are as follows.
①
Verifying and setting the measurement range.
Unless otherwise specified in your order, the value here is set to 0 to 3%TS, which is the
provisional set value at the time of factory shipment. Reset the value in accordance with the
operation condition of your plant. If the measurement range is specified in your order, verify
that the value is set as specified. If the value is different, reset it.
②
Verifying and setting the operation mode
At the time of factory shipment, this is set to "CONT" (the normal continuous operation
mode). In the event of the density meter being made empty due to pump shutdown or valve
closure, etc. or of using such a method that stops the flow for some time, it is recommended
that "EXT" (the external synchronized operation of switching between ON/OFF of
measurement by means of ON/OFF of the external contact input signal connected with the
pump ON/OFF) be selected.
In the event that the external synchronized operation is selected, the values of
delayed time
(dt) and output at contact OFF(ho) are the provisional set values at the factory shipment.
If the those values are meet to the operation conditions of the plant rest it to an appropriate
value in accordance with the operation conditions of the plant.
③
Verifying and setting the simulated output in setting mode.
Normal measurements are suspended while this density meter is in the setting mode (see "2
SETTING MENU"); thus, both the density display and the density output are given the
simulated values ( density test output (ot)) that are set beforehand. Although, at the time of
factory shipment, the value is provisionally set to "1.5%TS" (50% of the specified full-scale
density if the measurement range is specified), reset it to an appropriate value in accordance
with the operation conditions of the plant.
④
Verifying and setting the moving average times
At the time of factory shipment, the "moving average times" is set to 1 (without the moving
average). If the averaged output is required to be used for density control, etc., set it to about
10. The more the moving average times, the worse the responsiveness becomes with regard
to density variation. Therefore, set it to an appropriate value in accordance with the plant
conditions, including the right balance with the responsiveness.
⑤
For other measurement conditions, the standard values are set. Therefore, it is normally
unnecessary to change these settings.
[NOTE] “10 VARIOUS FUNCTION” describes various functions of the Density Meter LQ500.
If necessary, make additional settings for using these functions appropriately.
(2) Verifications at the time of normal power-ON
In the event that measurement conditions of the converter are already set with the operation not
being the first one since installation, verify the set value while referring to (1).