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8. Calibration
Connecting the unit with a strain gauge transducer and
setting how the indicator values will be shown is called “cali-
bration”. The following three calibration methods can be used
with the unit.
1. Equivalent input calibration
This calibration method does not depend on actual loads. It
only requires the input of the strain gauge transducer rated
output (mV/V) and the rated capacity (value you want shown).
Use this to calibrate easily when an actual load cannot be
applied.
Examples:
Load
100kN rated capacity, 2.001mV/V rated output
Pressure
10.00MPa rated capacity, 2.002mV/V rated output
Torque
15.00N·m rated capacity, 2.502mV/V rated output
In this manner, by recording values from test reports, the gain
can be determined automatically and shown.
2. Actual load calibration
This calibration method measures the values of actual loads on
the strain gauge transducer.
By applying an actual load that is as close as possible to
the maximum measured value, calibration with less error is
possible.
3. TEDS calibration
This calibration method uses the strain gauge transducer rated
output (mV/V) and rated capacity that are recorded in TEDS
memory.
Note, however, that equipment with TEDS memory includes
both 1kbit and 4kbit devices, but the unit only supports 4kbit.
A strain gauge transducer should have written test results with contents such as the following.
Rated Capacity
Rated Output
Linearity
Hysteresis
Safe excitation voltage (maximum)
Input Terminal Resistance
Output Terminal Resistance
Zero Balance
Load, barometric pressure, etc. (with units of kN, Mpa, etc.)
Voltage (unit: mV/V)
%R.O.
%R.O.
V (bridge voltage)
Ω
Ω
%R.O.
o
The data necessary for equivalent input calibration are rated capacity and rated output.
o
Some of this data is written to the internal memory of the TEDS sensor.
Sensor check before calibrating
After connecting a sensor and providing power, calibration is
not possible if the indicator value is unstable or the status indi-
cator lights magenta. If this occurs, check the indicator value
after issuing a Static Strain Display Switching execution com-
mand, setting it to Static Strain Display Mode. In this mode, the
sensor output itself is shown as a strain amount unit (μST), so
input between 0 and ±5.0 mV/V will be shown as a value from
0 to ±10000.
Overview of zero balancing and Digital
Zero functions
1. Zero balancing value definition
This is the value for which zero balancing is conducted
during the sensor calibration procedures in this chapter.
When Calibration Value Lock is ON, this setting value is
defined as the zero balancing value.
2. Digital zero (D/Z) value definition
The digital zero (D/Z) function that shows zero separately
from the zero balancing value can be used only when
Enable Digital Zero is set to ON.
