Honeywell R0512 Manuel D’Utilisation

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EXCEL 50/100/500/600/800 
ATTRIBUTES 
 
 
EN2B-0092GE51 R0512 
33 
 
Pseudo totalizers: 
In the event that you have selected the datapoint type "pseudo totalizer inputs," you 
must set the attribute "Scaling Factor" to "1"; otherwise, the number of pseudo 
totalizer inputs will not be counted. 
 
 
Sensor Offset 
The attribute “Sensor Offset” is designed for the compensation of the resistance of 
the sensor wiring for low-resistance sensors, like Pt 100, Pt 1000, Balco 500.  
The voltage offset due to the wire resistance is approximately constant, the attribute 
“Sensor Offset” functionality has therefore been designed to compensate constant 
voltage offsets at the analog input. 
 
 
Function principle 
The principle is that the attribute “Sensor Offset” can be defined at a selected tem-
perature, e.g., 1 °C at 20 °C. The Excel controller processes this temperature offset 
into a voltage offset, e.g., -0.11 V, and applies this very voltage offset for correcting 
(offsetting) all voltages measured. 
 
In order to display a temperature, the controller processes the resulting voltage 
back into a temperature. This principle and the processing (including mathematical 
rounding) from “°C” into “volt” and back into “°C” leads to slightly inconstant offsets 
across the temperature range. 
 
Example for a selected “Sensor Offset” of 1°C: 
 
Measured Temperature  
Corrected Temperature 
20°C 
 
 
19°C 
-10°C 
 
 
-8,4°C 
 
For XFL and XFC I/O modules, "Sensor Offset" functionality is supported from 
CARE 5.0 and controller firmware 2.06.05 onwards. 
 
 CAUTION 
Regarding sensor offset, the behavior of controllers with OS < 2.06.05 
engineered using CARE 4 differs significantly from controllers with OS 
2.06.05 and higher engineered using CARE 7 and higher.  
 
For example, for XL50 internal AI and XL500 internal AI (XF521/527 
modules), the sensor offset is subtracted from the datapoint value. 
 
For XL50 and XL800 controllers using XF821 modules, the sensor offset is 
added to the datapoint value. 
 
See also section “Sensor Offset Handling” in Excel CARE – User Guide 
(EN2B-0182GE51). 
 
 
Suppress Point 
The attribute "Suppress Point" means that datapoints are no longer processed and 
checked. As a result, no alarms are generated for suppressed points. Where you 
have flexible datapoints, this attribute acts upon all basic types of physical 
datapoints. 
 
IMPORTANT 
Never suppress a datapoint used via your application program. This 
causes system failure. 
 
 
Switching Down 
The attribute "Switching Down" is used in conjunction with flexible datapoints of the 
type "feedback". On switching down from one stage to another, it determines