Technical details about the sensor supply

Schematic diagram of the sensor supply

Ubatt internal supply voltage
F electronic fuse
R 330 Ω
USensor 0...22 V
Ex parameters
Uo 25,6 V
Io 82 mA
Po 0,523 W
  Lo [µH] Co [µF]
1000 0,31
250 0,36
100 0,465

The sensor supply is activated by setting a value for the warmup time in the input window "Universal input" (see Universal input). The warmup time specifies how long before the measurement the sensor supply is switched on. If it is set to 0sec., the sensor supply will neither be activated prior to nor during the measurement.

Tip: The time of the first recording following the PowerOn is calculated and is not completed exactly according to the time after the PowerOn specified via the record interval. If the record interval is 1 minute long, the first recording is selected in such a way that it is completed at the full minute mark. This means that if the PowerOn is completed at 12:05:34, the first recording is taken at 12:06:00, i.e. 26 sec. after the PowerOn.

 

Tip: Example to explain the correlation between warmup time and measurement cycle

Basic settingsMeasurement cycle 1min.
Measurement channel -> configurationWarmup time 20sec.
Output at the deviceSensor supply 

Explanation: The sensor supply is activated 20sec prior to the measurement interval each time, meaning that the value provided at the time of measurement is valid.

 

Tip: Example to explain the filter time in conjunction with the Ext. warmup time

Basic settings Record interval 5min.
Measurement cycle 1min.
Measurement channel -> configuration Ext. warmup time 1sec.
Filter time 500ms
Output at the device Sensor supply  

Explanation: The sensor supply is always activated 1sec before expiry of the measurement cycle. The filter time starts 500ms before expiry of the measurement cycle, which ensures that a valid value is available at the time of a measurement. However, this also means that the filter time must be taken into consideration when selecting the Ext. warmup time. In the current example, the sensor connected to the input must at the latest supply stable values 500ms following activation of the sensor supply. Otherwise, invalid values would be taken into consideration while averaging during the filter time resulting in the measurement value being distorted.