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8012426/YWL2/3-0/2016-08| SICK
O P E R A T I N G I N S T R U C T I O N S | DUSTHUNTER SP100
Subject to change without notice
START-UP AND PARAMETER SETTINGS
4
4.3.7
Calibration for dust concentration measurement
For exact dust concentration measurement, the relation between the primary measured
variable scattered light intensity and the actual dust concentration in the duct must be
established. To do this, the dust concentration must be determined based through a gravi-
metric comparison measurement according to DIN EN 13284-1 and set in relation to the
values measured at the same time by the measuring system.
Steps to be carried out
▸
Select device file “MCU”, set the measuring system to “Maintenance” mode
▸
Enter the Level 1 password (
see “Password and operating levels”, page 75
▸
Select the “Configuration / IO Configuration / Output Parameters” directory (
ET menu: MCU/Configuration/IO configuration/Output Parameters”, page 65
assign the “Scattered light intensity” measured variable to one of the three analog
outputs available.
▸
Estimate the measuring range required for the dust concentration in operational state
and enter this in the “Analog Output 1
(2/3)
Scaling” field assigned to the selected
analog output assigned to the scattered light intensity.
▸
Deactivate “Maintenance” mode.
▸
Carry out the gravimetric comparison measurement according to DIN EN 13284-1.
▸
Determine regression coefficients from the mA values of the analog output for “Scat-
tered light intensity” and the actual dust concentrations measured gravimetrically.
c:
Dust concentration in mg/m³
K2, K1, K0:
Regression coefficients of the function c = f (I
out
)
I
out
:
Current output value in mA
SI:
Measured scattered light intensity
LZ:
Live Zero
MBE:
Defined upper range limit value
(value entered for 20 mA;
normally 2.5 x fixed limit value)
NOTE:
Carrying out a gravimetric comparison measurement demands special knowledge that
cannot be described in detail here.
c
K2 I
out
2
⋅
K1 I
out
⋅
K0
+
+
=
(1)
I
out
LZ SL
20mA LZ
–
MBE
-----------------------------
⋅
+
=
(2)