EKO INSTRUMENTS CO., LTD. MS-56 Pyrheliometer Manual Ver.5
Pg. 15
6. Maintenance & Troubleshooting
6 - 1 . M a i n t e n a n c e
Once the MS-56 is installed, it is essentially free of any maintenance although care must be taken to keep the
instrument in the best condition for accurate measurement.
1. Data Verification
By analyzing the measurement data (such as irradiance and temperature), user can verify the condition of the
instrument. When abnormal data is found, either the sight of the pyrheliometer is not aligned or the instrument
has some defect. Check the condition of cable at the same time checking on the pyrheliometer setup
condition.
2. Cleaning of Quartz Window
Clean the quartz window with a soft cotton cloth and alcohol or demineralized water when it gets soiled. Since
soiling will have an effect on the performance of the radiometer by means of reduced optical transmission of
the solar radiation and consequently leads to a reduced detector output. Despite no proper indication can be
given on the required cleaning interval since it is strongly depending on the local environmental conditions
affected by Rain, Snow, Ice, Dust, Sand, or Salt. Environmental factors like frequent rain fall can also have a
positive effect on cleaning by washing off any sand or dust particles. For specific cases it might be an
advantage to remove the Rain Cap and benefit from this effect. The success of this approach can be
determined empirically.
3. Desiccant Inspection
Periodically the desiccants need to be exchanged to maintain a dry environment inside the pyrheliometer. The
frequency of replacement varies with the operating conditions on location but annual replacement is
recommended. The section at the next page shows how to replace desiccant.
4. Pyrheliometer Alignment
The measurement performance can also be inspected by carefully analyzing the measurement data (e.g.
irradiance and temperature). Any abnormality found in the data might be caused by misalignment of the
sensor or defect. At regular intervals, the quality of the cables can be checked like the alignment of the
pyrheliometer.
5. Clean the Sight
Sometimes rain and dirt maybe collected in the through-hole for the sight and the sight spot cannot be
confirmed. Clean and remove the water and/or dirt by using a small diameter pin.
6. Recalibration
EKO Instruments recommend to recalibrate the sensor every 2 years.
