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Hệ thống cân cấp liệu lò
Báo cáo chuyên đề
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LOW(loss of weight) cấp liệu bằng CF silo
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H th ng cân c p li u lò ệ ố ấ ệ
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Áp suât
ban đầu
Loadcell két
cân
Công tắc
báo mức
Van cánh
bướm
Máy thổi
sục khí
silo
Van một
chiều bằng
tay có công
tắc giới hạn
Van lưu
lượng
Van Shut
off
Khối
ngưng
nước
Các van tay
Sơ đồ nguyên lý của két cấp liệu
Máy thổi
sục khí két
Bình khí
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Định lượng
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Loadcell cân
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Schenck Load Cells
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Nguyên lý loadcell cân
Weighing cell exiting
voltage in mV
(approx. 24.000 mV)
Weighing cells mV ouput to PLC mV input module:
( )
( )
mV 27.32238 volt)(23.967 * mV/V) (2.85*
) tons(47*3
tons)(56.4
mV
: volt23.967 of voltageexiting cells measured and cells, weighingon the
load tons56.4 a Schenck, from cells mV/V 2.85 cells, g t weighin47 with Example
voltage)exiting (Cells * ty)senseabili (Cells*
load cell (Nominal*3
cells)on (Weight
output Cells
==
=
Weight on 3
weighing cells
Weighing cells
Constant (mV/V)
mV from
weighing
cells
Nominal
weight of
1 cells
Theoretical mV value
from weighing cell
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Measured weighing cell
exiting voltage in volts
(approx. 24.000 mV)
Same formula changed a little gives the load on the weighing cells:
( )
( )
tons48.4106
volt)(23.967 * mV/V) (2.85
t)(47*3 * mV) (23.452
cellson Weight
: volt23.967 of tage volexiting measured and cells, weighingon the load
on mV 23.452 measured and Schenck, from mV/V 2.85 cells, ng47t weighi with Example
voltage)exiting (Cells * ty)senseabili (Cells
load) cell (Nominal*3 * cells) from (mV
cellson Weight
==
=
Weight in tons on
3 weighing cells
Weighing cells
Constant (mV/V)
Measured mV from
weighing cells
Nominal load of 1
weighing cells
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Example:
3 Schenck load cells
Type RTN-15 0,1 % (total error)
Nominal Load per weighing cell 15 t
Sensitivity 2.85 mV/V
Trọng lượng đầu ra các loadcell
Rated output = weighing cells sensitivity (mV/V)
Vout = meassured signal (mV) from weighing cell
Rated capacity = sum of nominal weighing cells capacities
Vexc = Voltage applied to weighing cell (10.3 or 30 Vdc)
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