You have to manage the meter configuration and values each time a meter is replaced.
In WorkStation, in the System Tree pane, select the trend log whose meter configuration you want to manage.
On the File menu, click Properties .
In the End time box, enter the end time of the old meter.
In the End value box, type the value of the old meter when it was replaced.
In the Start time box, enter the start time of the new meter.
In the Start value box, type the current value of the new meter.
In the Meter constant box, type the constant value of the new meter.
Type the constant of the new meter if unit conversion is not used in the trend log, for example, the old trend log counted in grams and the new one counts in kilos (10 3 ) type 1000.
If unit conversion is used in the trend log - do not change the meter constant.
In the Min value box, type the first value of the new meter when it rolls over.
In the Max value box, type the last value of the new meter before it rolls over.
Click OK .