The tolerance time setting can be used in processes with intermittent breaks in the measurement due to non-representative sample on the prism. This typically occurs when there are large voids in the process liquid.
If the optical image can be interpreted, the tolerance time setting does not have any effect. When the optical image can no longer be interpreted (status messages, for example, NO SAMPLE, NO OPTICAL IMAGE, PRISM COATED), the measurement is held for the given number of seconds.
For example, a setting of 10 s ensures that any NO SAMPLE state which is shorter than 10 s does not make a dip into the output signal. The factory setting is 5 s. To se the tolerance time, access the 6 TOLERANCE TIME menu item.
The tolerance time counter is reset always when there is a representative sample on the prism (for example, the nD can be determined). The following figure shows this behavior with an intermittent measurement signal. When the signal drop is shorter than the tolerance time (for example, at t = 10 s or t = 35 s in the figure), the output signal does not drop. If the signal drop is so long that the tolerance time counter reaches zero, there is a drop in the output signal (at t = 80 s in the figure).
