FAQ

• Data Loggers

  • What is the extension of the log file of the LOGBOX SD?

    • The extension is .TXT or .XLS. Using the software interface you can select to save this as a text -or Excel file.

  • What is the format of the log file of the LOGBOX SD data logger?

    • The format uses columns,  for example:

      Date	Time	A1	A2	A3
      5-2-2009	10:59:03	3,079	38,763	0,693
      5-2-2009	11:00:03	3,108	38,763	0,697

       

  • How do I connect a Pyranometer with PT100 to the LOGBOX SD Data logger?

    • The picture shows how a PT100 is connected.  PT100 uses four input channels nr 1,2 ,3 and 4. Leaving 4 channels left, nr 5,6,7, and 8, to connect other sensors.

      Please note that the picture uses 2 analogue inputs for the instrument (differential). Of course you can decide to use it single ended, by connecting the – from the instrument to the GND.

      

  • Does the internal battery stop working when you power the Logbox SD with an external power supply? In this case, will you still have power available for excitation on the Power Out connection?

    • The LOGBOX SD has one input for power. You either connect the internal battery or an external power source. So external power will not switch of the battery.

      PWR OUT will provide whatever power is connected as power source for the LOGBOX SD.

  • How does a data logger work?

    • Every logger has an A/D converter with a certain resolution (number of bits) - often 10, 12, 16 or 24 bits resolution.  A logger also has a fixed number of analog input ranges - often 20 mV, 100 mV, 1 V, 5 V and 10 Volt ranges.

      For example we use a logger with 12 bits resolution and 5 Volt  input range.
      This means that the 5 Volt is divided in 2¹²  steps. This is 5/4096 = 0.00122 Volt per step. So the smallest detectable change on the input is 1.22 mV.

      If we connect an SP Lite(2) with a sensitivity of 75 microVolt/W/m^2, one Watt (change) will give 0.075 mV (change) on the output. So we need a change of 1.22 / 0.075 = 16.2 Watt/m² before we see a change in the Logger output.

      As you can understand this is not acceptable. A minimum of 1 W/m² should be detected (preferably a factor 10 times better). This can be achieved by lowering the input range to 100 mV (50 times better). Or by selecting a higher resolution e.g. 16 bits (in stead of 12 bits) this is 16 times better ( 2¹⁶- 2¹² = 2⁴ = 16 ).

  • Can I use the METEON in combination with the AMPBOX?

    • No, the METEON will not work together with the AMPBOX. With a 10 Ohm resistor the 20 mA output from the AMPBOX can be converted to 0.2 V max signal (max for the METEON). But the METEON cannot deal with the zero offset of the AMPBOX (4 mA).

  • Can the data from the METEON be downloaded into Excel?

    • Yes, inside the software, at the graphical chart, there is an export button. You can select the default .txt option or customize the extension into .xls.

  • Can a METEON data logger be connected to UVS-A-T and UVS-B-T?

    • No, the output of the UVS is 0-3V and this is too high for the METEON.

  • What is the logging interval for the METEON?

    • The logging interval can be selected from 2 to 65.535 seconds.

  • What is the operating life of the batteries of the METEON?

    • Two AA size internal Alkaline batteries will operate for approximately 1200 hours / 50 days.

  • How is the METEON powered?

    • With two AA size internal Alkaline batteries.

  • Can we use the METEON outside?

    • The METEON is not suitable for unprotected outdoor use. However, the operating temperature range is – 10 ºC to + 40 ºC. When it is placed in an enclosure protected from dust and rain, it would be possible in practice.

  • What is the difference between the SOLRAD and the METEON?

    • The SOLRAD can be used as a very cost-effective and well performing real-time interface to a PC serial port, logging the data on the PC with the supplied software.

      The METEON however, cannot do this. You need to download the data periodically using the supplied software. The METEON interface is USB.

  • I have an outdoor reading of 2000 to 4000 W/m² with my METEON. This does not make sense since theoretically, readings should be less than the solar constant (1360 W/m²).

    • Please check the calibration factor of the pyranometer which is set in the METEON. A wrong calibration factor of the instrument will result in wrong measurements. Also check if the correct instrument is selected.

      

  • If we take an interval of 1 minute then the sum of all the averages for 1 day it says 394838 W/m². If we set it for 30 minutes, then we will get 1 average per 30 minutes so the sum of all these averages for 1 day would be 13161 W/m². What are we doing wrong?

    • Adding the intervals without dividing this by the (interval) time.

      For example:
       
      Radiation in the morning 4 hours 400 W/m².
      Radiation in the afternoon 4 hours 600 W/m².
       
      If you would take a 60 minute interval on the same day:
      Morning = 4 intervals of 400 W/m²
      Afternoon = 4 intervals of 600 W/m²
      Total over the day 4 x 400 + 4 x 600 = 1600 + 2400 = 4000 W/m² (over hourly interval)
      This is 4000 W/m² per hour or 4000 Wh

      The stored interval in METEON is 30 minutes.
      During the morning you will get 8 intervals of 400 W/m²
      During the afternoon you will get 8 intervals of 600 W/m²
      16 intervals (of 30 minutes) with a total of 8 x 400 + 8 x 600 = 8000 W/m² (over 30 min interval)
      This is 8000/2 = 4000 W/m² per hour or 4000 Wh

  • Can a SOLRAD data logger be connected to UVS-A-T and UVS-B-T?

    • Yes, the SOLRAD is perfect because it has a 0-10V input range available (the output of the UVS meter is 0-3V ).

      Please consider that the SOLRAD is intended to display real-time values and/or to store the integrated values for a day. If you fully want to use data logger options it is better to use a LOGBOX SD.

  • How can we program the SOLRAD for the output to be in W/m² ?

    • The UVS has a ‘Mean Adjustment Factor’ on the calibration certificate.  This is equivalent to the sensitivity of a Pyranometer.  This can be entered into the SOLRAD and the readings will be in W/m².

  • I understand the SOLRAD is not really a data logger. Is this correct?

    • The SOLRAD is not a data logger. It is intended to display real-time values and/or to store the integrated values for a day. 31 records allows a month of daily integrated values to be stored. 

  • How is the SOLRAD powered?

    • The internal battery will only run it for a little more than one day. For longer periods it requires an external DC supply.

  • Can we use the SOLRAD outside?

    • It is not suitable for unprotected outdoor use. However, if it is in an enclosure protected from dust and rain it would be OK in practice.

  • How long can I record data on my COMBILOG data logger

    • This depends on the number of recorded channels and storage interval. A detailed description of the storage capacity can been found in the COMBILOG manual, available on it's product page.

      In case you want to quickly calculate the storage capacity in days for your application, please use the calculation tool below.

      Please enter your desired settings for the data logger:
      Number of Channels:
      Storage interval [seconds]:
      	Calculate
      Total number of days recording time:
      With standard internal memory:
      7MB		Days
      With optional SD-card:
      1024MB / 1 GB:		Days