Questions Answered

The sensitivity of any solar sensor deviates over time when exposed to solar radiation. Most sensors have a recommended 2-year recalibration interval.

However, thanks to superior design, build quality and stability, many of our class and industry-leading sensors, including the Class A MS-80 and MS-80S Pyranometers, and MS-57 Phyrheliometer, have a 5-year recommended recalibration interval.

Your sensor should have come boxed with a calibration certificate showing the date of the original calibration and recommended recalibration interval. But, if your sensor has been stored correctly, you can calculate the actual recalibration date, based on the recommendation, from the date of installation or first use.

The calibration is not altered when the product is not used.

EKO Instruments offers Pyranometer, Pyrheliometer & Viscometer recalibration from our accredited global calibration laboratory in Tokyo, Japan. Pyranometer recalibration is also available at our laboratory in the Netherlands.

All EKO products come with a minimum 2-year warranty.

Some products, including the IS0 9060:2018 Class A MS-80, MS-80S Pyranometer and MS-57 Pyrheliomter come with a 5-year warranty.

Check the product manual and documentation you received with your sensor to confirm the warranty conditions or contact your local EKO sales representative.

‘Soiling’ is when the dome or window on your sensor becomes dirty or otherwise blocked with dust or frost, for example.

When measuring solar radiation with pyranometers, pyrheliometers or spectroradiometers, soiling can affect the radiometer output or measured irradiance (re. accuracy) of your data.

EKO sensors are designed to reduce the impact of soiling, and our range of S-Series sensors with in-built diagnostics, and digital outputs, can help to manage and further mitigate the effects of soiling with easy access to sensor status and measured data.

Even so, soiling can occur and should be analysed case-by-case. Regular rain, for example, can have a positive effect, minimising the impact of soiling. On the other hand, dry weather can lead to more dust deposition on the dome over time. Local conditions and changing weather make it difficult to predict when your sensor may need cleaning; however, rain, snow, ice, dust, sand, and salt are the most common causes of soiling, so keep an eye on these conditions and the data from your sensor.

If you do notice that your sensor’s dome or window is affected by sand or salt residue, please clean the quartz window with a soft cotton cloth and alcohol or demineralised water.

Outdoor PV modules are even more prone to soiling. Small particles on the transparent surface of the modules cause light to diffract, reducing the amount of solar energy reaching the sensitive surface of the cell. As a consequence, the modules’ power output will drop proportionally. Monitoring and maintaining your sensors will help you catch and mitigate the impact of PV module soiling considerably.

EKO sensors are designed to reduce the impact of soiling, and our range of S-Series sensors with in-built diagnostics, and digital outputs, can help to manage and further mitigate the effects of soiling with easy access to sensor status and measured data.

Even so, soiling can occur and should be analysed case-by-case. Regular rain, for example, can have a positive effect, minimising the impact of soiling. On the other hand, dry weather can lead to more dust deposition on the dome over time. Local conditions and changing weather make it difficult to predict when your sensor may need cleaning; however, rain, snow, ice, dust, sand, and salt are the most common causes of soiling, so keep an eye on these conditions and the data from your sensor.

In general, it is recommended to check and clean the dome every week. However, that may not always be possible, and many large PV sites or remote applications may have longer maintenance intervals. Data redundancy, that is, multiple instruments used together to analyse and compare irradiance data, will help you to understand the effect of soiling, identify trends, and customise your maintenance plans.

Though we do offer a range of spare parts and supplies our advice to customers, whenever they have an issue or question about their sensor, is to get in touch. Our service team will work with them to assess their needs and the best solution.

You can also find compatible accessories on individual product pages.

Whether your product is under warranty or not, contact your local EKO office using our online contact form, to discuss your situation and find out how we can help

All EKO products are built to the highest quality standards and are thoroughly tested and calibrated during production.

Even so, regular inspection of your sensor and data is advised to ensure consistent performance. Instant changes to the regular data pattern or collocated measurements, for example, may indicate a performance change or issue that necessitates servicing or recalibration.

Data redundancy, that is, multiple instruments used together to analyse and compare irradiance data, can also help you catch any issues.

The internal diagnostics systems of our S-Series range of sensors are another big help, giving users visibility over internal temperature, humidity, tilt and roll angle, helping to ensure optimum performance without the need for regular physical checks.

If you have any doubts or questions about the performance of your sensor, please contact your local EKO office using our online contact form.

Our STR-21G and STR-22G sun trackers do not require recalibration or re-adjustment. They are built to automatically track the sun’s position through calculation and active measurement of the sunspot.

Time information used for the solar position algorithm is retrieved by the GPS receiver and is frequently updated. The sun sensor actively measures the actual position of the sunspot and compensates for misalignments.

Find out more and explore available downloads for the STR-21G by visiting the product page.

We recommend a monthly check to ensure that the sun tracker cables and cables for all associated solar sensors are still in place, that the sun tracker is still at a horizontal level and that the sun sensor front window is not dirty.

Other than that, no specific maintenance is required.

EKO Instruments Co., Ltd. (EKO) calibration laboratory is accredited and certified by PJLA (Ref: #74158) to perform pyranometer and pyrheliometer calibrations per the requirements of ISO/IEC 17025:2017, which are relevant to calibration and testing.

EKO was the first manufacturer in the world to offer an in-house calibration service for pyranometers and pyrheliometers, and we provide a calibration certificate with all new and recalibrated pyranometers and pyrheliometers.

Customers can have the highest level of confidence when purchasing an ISO/IEC 17025:2017 calibrated sensor, or when sending an existing sensor to us for recalibration. EKO’s accredited laboratory status is regularly re-examined to ensure that we maintain the required standards of technical expertise.

EKO Instruments offers Pyranometer, Pyrheliometer & Viscometer recalibration from our accredited global calibration laboratory in Tokyo, Japan.

EKO offers pyranometer recalibration at our laboratories in Japan and the Netherlands. We also work with a network of partner organisations, including specialised laboratories, meteorological institutes, and universities, to offer recalibration services worldwide.

You can book a recalibration via our services page. For more details or questions about available recalibration services in your region, please contact your local EKO office via the contact page.