Lamtec LT 2 Assembly And Commissioning Manual page 46

4 Technical Description
Limit value 1 (2,3,4) affects (parameters: 930/940/950/960)
Max. comparative value (param. 931/941/951/961) / Min. comparative value (param. 932/942/952/962)
Off:
Constant value:
Calculated analogue
value:
Max. LV constant (param. 933/943/953/963) / Min. LV constant (param. 934/944/954/964)
Example 1:
Example 2:
This parameter indicates which reference value is to be monitored. The following
reference values are available for monitoring:
• Off - The limit value is momentarily not in use.
• O measurement value
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• Configurable measurement values: one of six possible measurement values
defined by the user is monitored.
• Probe internal resistance Ri probe
• Probe voltage U-O
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Three possible settings are available for the upper and lower comparative value:
The comparative value is not active.
A constant reference value is chosen as the comparative value.
A value calculated from the O
reference value. In the LT 2/KS1-DK lambda transmitter, one of 12 different available
reference values may be selected. Configuration of the analogue values to be
calculated.
If a constant value is selected as the reference value, this constant is defined in Max.
or Min. LV. Please note that only integer values can be entered here. If the constant
reference value is shown in the display with decimal places, the sequence of numbers
in the reference value must be entered with the decimal point omitted.
The O measurement value is to be monitored, the limit value output must be set as
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follows:
Undershoot at 5.5% and exceeded at 15.6 vol.% O
A constant value is set as default for the Min. or Max. reference value:
- For the Max. LV constant: 156
- For the Min. LV constant: 55
NOTE:
If you wish to monitor the measurement value only for instances where it exceeds or
undershoots the limit values, set the switching threshold in such a way that it never
responds.
Example: You wish to monitor the O
undershoots the minimum limit. Set max.
You wish to monitor the probe voltage U-O
display in mV without decimal places. You must enter the limit values as integers in
mV. Thus, entering 100 corresponds to 100 mV.
actual value or an analogue input is employed as the
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measurement value only to ascertain if it
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limit value to 30,0% (300).
. The voltage value is shown in the
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