Hukseflux 2403 Thermal Sensors User Manual
- June 1, 2024
- Hukseflux
Table of Contents
Hukseflux 2403 Thermal Sensors
Specifications:
- Manufacturer: Hukseflux
- Product: Thermal Sensors
- Communication: RS-485 for latest pyranometer models
- Software: Internal software for sensitivity correction
- Standards: IEC 61724-1, ISO 9060, ISO TR 9901, ASTM G213
Product Usage Instructions
Objective of the Workshop:
The in-company workshop aims to provide insights into solar radiation
measurement for PV system performance monitoring.
Discussions include standards compliance, instrument classification,
recommended practices for use, maintenance, inspection, and calibration.
Management Summary:
The workshop covers topics related to solar radiation measurement and
system optimization. The content is also briefly summarized in the following
pages.
Major Updates:
The latest pyranometer models feature digital communication over RS-485,
replacing traditional analogue outputs. Hukseflux provides internal software
for sensitivity correction after recalibration.
Increasing Instrument Performance:
Emphasis is placed on using spectrally flat Class A instruments and PV
reference cells for POA measurements. The focus is on stability, accuracy, and
universality across different cell types.
Formalities:
Investors are increasingly seeking formal documentation for PV monitoring
systems. Test certificates are provided with each instrument, and asset
managers may request proof of performance verification during production and
maintenance.
Focus on Data Availability:
Data availability is a key aspect of the workshop discussions. The importance
of characterizing pyranometer responsivity, considering temperature and
irradiance angle is highlighted for accurate measurements.
FAQ:
Q: Can I access the latest updates on Hukseflux Thermal Sensors online?
A: Yes, for the latest information on Hukseflux Thermal Sensors, visit
www.hukseflux.com or contact them via email at
[email protected].
In-company workshop: solar radiation measurement
Experts from Hukseflux explain and discuss recent developments in solar
radiation measurement for PV system performance monitoring at your company
An accurate measurement of solar radiation is the backbone of PV system
performance assessment. In our in-company workshop, we discuss PV system
performance monitoring according to the IEC 61724-1 standard. You will also
get the latest insights in instrument classification according to ISO 9060,
recommended practices for use, maintenance, inspection and calibration
according to ISO TR 9901 as well as an introduction to ASTM G213 on
uncertainty evaluation. In many cases, we can help save costs.
Objective of the workshop
The in-company workshop is offered to you free of charge by Hukseflux. We present the latest developments in solar radiation measurement and help you optimise system design, measurements and maintenance.
Management summary
Asset managers increasingly insist on having the highest accuracy – class A –
monitoring systems according to the latest IEC 617240-1 standard for PV system
performance monitoring. The standard requires instruments with the right
paperwork (according to ISO 9060), dew and frost mitigation by heating, and
regular (recorded) inspection and recalibration as proof of reliable
performance.
IEC Class A – grade monitoring records increase the PV power plant’s value.
This high-level quality assurance is also useful when legal issues arise, for
example, warranty claims.
The latest trends in PV monitoring are:
- measurements according to IEC 61724-1 Class A, including quality assurance: regular cleaning, inspection and re-calibration
- implementation of the new recommendations for monitoring of bifacial PV systems
- use of digital sensors for easy instrument exchange, and cost savings on cabling
- use of highest accuracy – Spectrally Flat Class A – instruments
- improvement of data availability by mitigation of dew and frost using heating
- uncertainty evaluation according to ASTM G213
Each topic is discussed during the in-company workshop and (briefly) on the following pages.
Major updates of IEC 61724-1
The IEC 61724-1: Photovoltaic system performance monitoring – Guidelines for measurement, data exchange and analysis – has been updated in 2021. It not only defines the measuring system components and procedures (as in the 2008 version), but also aims to keep measurement errors within limits. It does so by establishing accuracy classes for monitoring systems.
The new 2021 standard includes:
- 2 accuracy classes, A and B, for monitoring systems, to be used in conformity declarations. The 2017 Class C is now Class B
- accuracy requirements for monitoring equipment per class
- required quality checks (i.e. calibration and cleaning) per class
- recommended minimum number of instruments used as a function of the PV system scale
- new in 2021: requirements for reflected radiation and albedo measurement
- new in 2021: requirements for tracker tilt measurement
From analogue to digital
While traditional pyranometers have analogue outputs, the latest pyranometer models communicate over RS-485.
Advantages:
- use of digital sensors for easy instrument exchange, exchangeable sensors
- no possibility to manipulate data
- on-board calibration history records
Potential disadvantages are:
- not all calibration laboratories can handle these digital sensors
- not all manufacturers allow access to the internal software to correct the sensitivity after recalibration. Hukseflux does!
Increasing instrument performance
The use of lower accuracy than spectrally flat Class A instruments and the use of PV reference cells for POA is decreasing; these sensors are not sufficiently stable and not universally applicable with every cell type. The temperature dependence and directional response of PV reference cells is a major issue because these are not specified or standardised.
Formalities: test certificates with every instrument
The approach of investors tends to get more formal. When auditing PV
monitoring systems, asset managers ask for documented proof of performance
verification during the production of instruments as well as field maintenance
records.
ASTM 2848-11, covering test methods for PV systems, states: “Pyranometers are
sensitive to both temperature and the angle of incidence of irradiance” and
recommends: “that pyranometer responsivity be characterized to the extent
practicable”.
Focus on data availability
Dew, frost and snow deposition cause significant non-availability of data; as
shown in Figure 2.
The trends to improve data availability is:
- heating of pyranometers
Figure 4 Uncertainty evaluation according to the ASTM Guide G213 of a measurement of Global Horizontal Irradiance (GHI) on a sunny day, expressed in W/m2. The maximum value around solar noon is 1000 W/m2. The different colours represent different error sources.
Uncertainty evaluation/data analysis using ASTM G213
Measurement accuracy does not only depend on instrument properties but also on
measurement conditions:
- a very accurate instrument, like the class A sensors mostly used in the PV industry, will quickly underperform without a regular schedule of maintenance and calibration
- assessment of data availability and rejection of data are integral parts of the evaluation of the measurement. Data is eventually presented including a measurement uncertainty
ASTM International has released the G213-17 “Standard Guide for Evaluating
Uncertainty in Calibration and Field Measurements of Broadband Irradiance with
Pyranometers and Pyrheliometers”. It provides guidance and recommended
practices for evaluating uncertainties when calibrating and performing outdoor
measurements with pyranometers and pyrheliometers. In conformity declarations,
providers can now refer to this standard
Figure 6 Individual testing of every instrument; Hukseflux performs individual
testing of temperature response and directional response of all Class A
instruments.
NEW : pyranometers recommended practice for field use ISO TR 9901 ISO TR 9901 has been revised in 2021. Hukseflux can give a quick overview!
Hands-on with the sensors
During the workshop, several sensors can be demonstrated. Users will be able
to find out for themselves how easy it is to use them.
Saving costs on system and maintenance
You can save costs in many ways, for example, by paying attention to the
design of the monitoring system; we can assist in optimising power supply
cabling, dew and frost mitigation, and measures to improve immunity to high-
impulse voltages and charges- surges. We can also assist in saving costs of
calibration.
Measurement versus model
Modellers increasingly use virtual representations or “digital twins” in
system analysis. Show us what your digital twin needs as input so that we can
optimise.
Cost of Ownership
Asset managers increasingly accept the need for regular recalibration of the
PV plant monitoring systems. Calibration of Class A pyranometers is not easy,
and can only be performed by a limited number of organisations.
For pyranometers under a professional
maintenance regime, the total cost of ownership over the instrument’s lifetime
will not only be determined by costs of purchase but also by maintenance
costs.
On the side: use of PV module temperature sensors
The measurement of PV module temperature has a significant impact on the
measured performance ratio. Users should carefully select and install such PV
module temperature sensors. Poorly designed sensors will measure with a lower
accuracy than the 2 ˚C
required by IEC 61724-1.
Figure 7 PVMT01 installed on the rear side of a PV module. The sensors are
preferably installed at the centre of a cell close to the centre of the
module. IEC requires 3 sensors per monitoring station.
The role of monitoring parties
Asset managers increasingly separate the responsibilities for PV plant
operation and performance monitoring. The role of the monitoring party will,
in our opinion, concentrate on the analysis and quality assurance of the data,
including instrument maintenance and calibration. A major challenge is to
perform maintenance and recalibration of pyranometers efficiently.
About Hukseflux
Hukseflux is the leading expert in the measurement of energy transfer. We
design and manufacture sensors and measuring systems that support the energy
transition. We are market leaders in solar radiation and heat flux
measurement.
Customers are served through our headquarters in the Netherlands, and locally
owned representative sales offices in the USA, Brazil, India, China, Southeast
Asia and Japan.
Interested in having this workshop at your company?
E-mail us at : [email protected]
Copyright by Hukseflux. Version 2403. We reserve the right to change specifications without prior notice. For Hukseflux Thermal Sensors go to www.hukseflux.com or e-mail us: at [email protected]