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６．STARTUP
6-1．Warming-up
The Dust Monitor needs to warm up for approximately one hour after the power supply
is turned on.
6-2．Measuring Range
After warming up, set the optimum measuring range. First, set the Range Switch to
“1～4” if the flow speed is constant, the operation of the filter is normal,
and the dust is the environmental conditions are normal.
When the watch of a smaller change is necessary, a detailed change can be observed
by setting the range between “5～9”.
(However, it becomes easy for the overrange to do when the density is high. )
4mA(0%) 20mA(100%) 4mA(0%) 20mA(100%)
Measuring range1 ： 0.1 ～ 1000mg/m
3
Measuring range6 ： 0.1 ～ 20mg/m
3
Measuring range2 ： 0.1 ～ 500mg/m
3
Measuring range7 ： 0.1 ～ 10mg/m
3
Measuring range3 ： 0.1 ～ 200mg/m
3
Measuring range8 ： 0.1 ～ 5mg/m
3
Measuring range4 ： 0.1 ～ 100mg/m
3
Measuring range9 ： 0.1 ～ 2mg/m
3
Measuring range5 ： 0.1 ～ 50mg/m
3
Use the Range Switch described in section
5. OPERATION METHOD
to set the measuring range.
The numbers on the switch correspond to the ranges.
Attention: The rotate switch has numbers from 0 to 9 on the switch, but only 1 to 9 are used.
Number 0 is the Maintenance mode .
(Refer to
10. MAINTENANCE MODE
.)
The Dust Monitor uses “talc” as standard powder and is designed so that 20mA
will be output at 1000 mg/m
3
, which is the maximum range in a 10 m/s flow speed environment.
Each range is designed so that 20mA will be output at the maximum value of each range.
The linearity of the output at 1000 mg/m
3
will not change.
【Reference: Talc】
Talc is finely pulverized ore and gray-white, smooth inorganic powder.
Talc is chemically called hydro-silica magnesium [Mg3Si4010 (OH)] of which main components
are; approx. 60% of SiO2, approx. 30% of MgO, and 4.88 % of crystal water.
Its physical characteristics are; true specific gravity of 2.7 to 2.8, the hardest among
the inorganic minerals (Mohs’ hardness 1), excellent in heat resistance, and
chemically stable.
6-3．Precautions: What Is Density of Tribo-electric System Dust Monitor
The output value of the Dust Monitor of the Tribo-electric System varies according to
various environmental factors such as “kind of particle”, “diameter of
particle,”“gravity,” or “flow speed” due to its measurement principle, which can
be seen in the formula in section 1.
However, the linearity will not change except under certain environmental conditions.
For the density of the Dust Monitor of the Tribo-electric System, consideration must be
given to the influence by changes of physical characters as mentioned above.
Therefore, it does not always correspond to the density specified in section 6-2.
The density described in section 6-2 is assumed to be at the stages of design and development
of the Dust Monitor, and announced as the guideline for the user to determine the range.
When the user determines the range, check the pulse signal percentages output between
0% and 100%, and then set the appropriate values.
In this way, the tendency of the discharged dust density in the facility can be controlled.
When the density control is needed, the user must determine the density corresponding
to 0% to 100% signals.
After determining the range (0% to 100%) of the density control, check the actual density
when a pulse signal is input to the Dust Monitor.
After that, adjust the range or integral function to obtain the current signal optimal
to the actual density so that the user can read the signal as density from the current
signal of the Dust Monitor.
(This value is not an absolute value but a relatively converted value.)
!