ISR 12-LO
•
IGAR 12-LO Operating Manual
Settings / Parameter Descriptions
•
28
Operation note:
Dependent on the settings the maximum value storage either works in single
storage mode or in double storage mode:
Single storage:
The single storage is used when you want to reset the stored value using an
external impulse via one contact closure from an external relay (i.e. between two measured
objects). The relay contact is connected directly to the pyrometer between pins J and K. This
mode allows a new value to be established, after each impulse from the reset signal.
Double storage:
When entering the reset intervals via push buttons or PC interface the double
storage is automatically selected. This mode utilizes two memories in which the highest
measured value is held and is deleted alternately in the time interval set (clear time). The other
memory retains the maximum value throughout the next time interval. The disadvantages of
fluctuations in the display with the clock frequency are thereby eliminated.
Note:
The maximum value storage follows the function of adjustment of exposure
time. This results in:
•
Clear time
≤
the adjusted response time is useless.
•
Clear times must be at least 3 times longer than the response time.
•
Only maxima with full maximum value can be recorded, which appear at
least 3 times longer than the response time.
4.9
Operating mode
The series 12 pyrometers are designed for use in ratio mode. Additionally,
the pyrometers can be used in two other modes:
In the mono mode the pyrometer only, measures in one wavelength and the
ratio mode is off. In this case the operating mode is equivalent to a
conventional 1-color pyrometer (see
4.6, Emissivity
).
The metal mode is a special mode which calculates the temperature combining the ratio and the
1-color signal with an algorithm. The metal mode can be used to determine the temperature of
metals and alloys with unknown emissivity ratio (K). It should be used only for a short time to
achieve a good approximation of the object temperature if the temperature reading in 2-color
or 1-color mode seems to be incorrect. After this the pyrometer must be switched back into
2-color mode and the temperature reading has to be corrected with the adjustment of the
emissivity slope K until the instrument shows the temperature determined in the metal mode. A
condition for the use of the metal mode are settings of
ε
= 1 and K = 1.
Note:
Metal mode can be affected by the setting of the switch-off level, see (
4.10
).
4.10
Switch-off level (OFF / %)
The switch-off level is a function to avoid measuring errors caused by too low
signals. Ratio pyrometers can measure temperatures correctly even with very
low signals, i.e. for example through a dirty viewing window or if dust exists
in the field of view or if the spot is not filled by the measuring object. If the
signal is too low for a correct measurement, the pyrometer interrupts the
measurement and displays 1° below of beginning of the temperature range. Depending of the
application the switch-off limit can be adjusted between 2 and 50%, ex works at delivery set to
10%.
Note:
The smaller the value the higher the chance that daylight or reflections affect
a correct measurement.
Settings:
mono mode
ratio mode
metal mode
Settings:
2%
. . .
50%
