Calibration; General Description - Valmet SMART-PULP Operating And Installation Instructions

SMART-PULP

2.3 CALIBRATION

After installation you calibrate the transmitter for each pulp type. Ensure that the configuration described in
section 2.2 has been completed before you start calibration. You can save precalibrations for 8 pulps or pulp
mixes in the transmitter's memory. The Calibration menu contains the following 4 submenus:
1. NEW RECI (New Recipe) 2. SAMPLING (Take Sample)
3. LABORATO (Laboratory) 4. SP.GRADE (Special grade correction for recipe number one)

General description

Figure 2.3a shows the calibration
principle.
Calibration curves for several
applicable pulp types are saved in
SMART-PULP's memory for each
sensor type.
The calibration curves,
experimentally defined in Valmet
Automation's laboratory, represent
consistency (% Cs) as a function of
the shear force (N) acting on the
sensor.
In the transmitter's post-installation
calibration you tune the selected
calibration curve for the pulp to be
measured on the basis of
consistency samples. The tuning is
done either as single-point calibration
to define the zero offset P2, or as
two-point calibration where you also
define the curve's slope correction
P1 (see Fig. 1.3b). The original
curve's P1 = 1 and P2 = 0. In
sample-based calibration SMART-
PULP will itself calculate corrections
P1 and P2 in accordance with
laboratory results and samples.
You can save 1-8 calibrations for
different pulp types in the
transmitter's memory. You can take
the desired calibration into use either
directly from the transmitter or with
remote selection through binary
inputs or HART® (MODBUS).
Calibrations etc. operations are
carried out through menus. You do
not have to make any mechanical
settings. Calibration data is
preserved in memory even if power
is not switched on.
Smart Consistency Transmitter
RECIPE 1
Pulp type
Filler %
Slope factor
P1
Zero offset P2
Figure 2.3a SMART-PULP Calibration
LL
LS
JL
Calib curves/
Pulp types
UL
Shear force N
Selection of sensor-specific
set of calibration curves
Recipe definitions
Sampling
Consistency
analyses and
calibration
Selection of
active recipe
Pulp type
Filler %
Slope factor
P1
Zero offset P2
23
BCs160VA
Nov. 15, 1997
GL
RL
WS
HL
RECIPE 8
Pulp type
Filler %
Slope factor
P1
Zero offset P2
Operator Terminal,
Binary inputs,
®
HART , MODBUS
ACTIVE RECIPE