Campbell DustVue User manual

Revision: 08/2023
Copyright ©2023
Campbell Scientific, Inc.
DustVue
In-Field Soiling Measurement for
Operational and Site Assessment
(IEC 61724-1 Compliant)
PRODUCT MANUAL

Table of contents
1. Introduction 1
2. Precautions 1
3. Initial inspection 2
4. QuickStart 2
4.1 Configuration 2
4.2 User entered values 4
4.2.1 Definitions of UserEntered and solar panel 5
4.3 View data 6
4.4 Modbus settings and data 7
5. Overview 8
6. Specifications 9
6.1 Back-of-module temperature measurements 9
6.2 Modbus TCP communications 10
6.3 System 10
6.4 Power requirements 10
6.5 Compliance 10
6.6 Maintenance button 11
7. Installation 11
7.1 Connector panel 11
8. Operation 12
8.1 Measurement 12
8.2 Soiling loss index details 12
8.3 Offset correction 13
9. Maintenance 14
Appendix A. Variable description 15
Appendix B. Modbus register map 17
Table of Contents - i

1. Introduction
The DustVue Soiling Loss Sensor provides solar energy professionals with information needed to
evaluate and manage the impact of soiling on power production at the site. Plant operators can
use this information to determine when to clean the array, which saves the cost of unnecessary
cleanings and also helps to minimize damage caused by frequent cleanings.
The DustVue is designed to be the principle component of an independent soiling measurement
station, or as an add-on peripheral to any new or existing meteorological station. The DustVue is
delivered field ready and requires no programming. The DustVue will work with any photovoltaic
(PV) panel up to 700 W. Smaller wattage panels can be used. Consult Campbell Scientific before
purchasing if using a panel smaller than 20 W. Two highly accurate and rugged back-of-panel
temperature sensors are included.
2. Precautions
READ AND UNDERSTAND the Safety section at the back of this manual.
DANGER:
Fire, explosion, and severe-burn hazard. Misuse or improper installation of the internal
lithium battery can cause severe injury. Do not recharge, disassemble, heat above 100 °C (212
°F), solder directly to the cell, incinerate, or expose contents to water. Dispose of spent lithium
batteries properly.
WARNING:
• Protect from overvoltage.
• Protect from water.
• Protect from ESD (electrostatic discharge).
IMPORTANT: Maintain a level of calibration appropriate to the application. Campbell Scientific
recommends factory recalibration of the DustVue every three years.
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3. Initial inspection
The DustVue ships with the following:
lDustVue enclosure
l2 back-of-panel temperature sensors: CS241-17-PT Surface-Mount Temperature Sensors
lUV-resistant 8 in. cable ties used to secure the temperature sensor cables
lFlat-bladed screwdriver for connecting wires to terminals
lUSB 2.0 Cable Type A Male to Micro B Male for computer communications
lCR310 Certificate of Calibration
l8 GB USB flash drive with Device Configuration Utility software
Upon receipt of the DustVue, inspect the packaging and contents for damage. File damage
claims with the shipping company.
Immediately check package contents. Thoroughly check all packaging material for product
components that may be concealed. Check model numbers, part numbers, and product
descriptions against the shipping documents. Model or part numbers are found on each product.
On cabled items, the number is often found at the end of the cable that connects to the
measurement device. The Campbell Scientific number may differ from the part or model number
printed on the sensor by the sensor vendor. Ensure that you received the expected cable lengths.
Contact Campbell Scientific immediately about discrepancies
4. QuickStart
4.1 Configuration
Device Configuration Utility software is required to set time, set/view IP addresses, change
Ethernet settings, and view data. This software can be installed from the USB drive sent with the
DustVue. It is also available as a free download at www.campbellsci.com/devconfig.
1. Open the Device Configuration Utility
2. In the Device Type panel, select CR300 Series.
3. Follow the steps shown in the right panel of the window to connect.
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4. Set the Ethernet settings
a. Select the Deployment tab.
b. Fill in the Ethernet information appropriate for your network.
c. Press Apply on the bottom left of the screen to save the Ethernet network settings.
5. Set time. Although set at the factory, confirm time settings are correct and if necessary,
reset the clock at the time of deployment.
a. In the Logger Control tab use the drop down next to Reference Clock Setting and
select UTC (Greenwich Mean Time). Click Set Clock to apply the setting.
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4.2 User entered values
UserEntered values will be applied at the factory prior to shipping if they are provided to
Campbell Scientific when the DustVue is ordered.
Confirm all UserEntered values are entered correctly at the time of deployment.
CAUTION:
Be sure to check the Longitude_UserEntered,TempCoefflscTest_UserEntered,TempCoefflscRef_
UserEntered,IscTeststc_UserEntered, and IscRefstc_UserEntered values.
If any UserEntered values need to be changed, do the following the steps:
1. Select the Data Monitor tab.
2. Select the AllUserInputs table.
3. For each value that needs to be changed, do the following.
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a. Double click on the value in the field that needs to be changed:
b. Enter the correct value:
c. Press Enter to set the correct value.
4. When all values are corrected, set the ApplyandRestart variable to 1 and press Enter to reset
the system and apply all the values.
4.2.1 Definitions of UserEntered and solar panel
Table 4-1: User entered values and descriptions
Variable name Description
UTC_Offset_UserEntered User-entered UTC offset of site location, hours
Latitude_UserEntered User-entered latitude of site location
Longitude_UserEntered User-entered longitude of site location
TempCoefflscTest_UserEntered
User entered temperature coefficient of Isc of the test panel.
Default = 0.105%/°C. Configured at the factory if value is
provided
TempCoefflscRef_UserEntered
User entered temperature coefficient of Isc of the reference
panel. Default = 0.105%/°C. Configured at the factory if value
is provided
IscTeststc_UserEntered Published panel short-circuit current (Isc) of the test panel at
STC
IscRefstc_UserEntered Published panel short-circuit current (Isc) of the reference
panel at STC
HrSolNoonOffset_UserEntered
User editable field that defines the number of hours before
and after solar noon that will include measurements for
calculating soiling index. Default = 2 hours
GeffThreshold_UserEntered User editable field that defines the minimum effective
irradiance for calculating soiling index. Default = 500 W/m2
Stable_Data_Count_UserEntered
User editable field that defines the minimum number of
stable data counts for (re)calculating soiling index. Also the
minimum number of stable data counts for performing an
offset correction. Default = 20
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Table 4-1: User entered values and descriptions
Variable name Description
ModBus_ID
User editable field defining the Modbus address. Default = 11
(should not require modification for Modbus TCP
Communication)
ApplyAndRestart Enter a value of 1 to save user entered/edited values and
restart the DustVue
4.3 View data
The DustVue outputs data over Modbus TCP (see Modbus register map (p. 17). Live data is shown
in the Public table. To verify the system is working as expected, review the Raw_Measurement_
Data and the Modbus_Register_Map values.
The soiling loss index, based only on short-circuit current and effective irradiance (including
temperature correction), will show the previous days soiling loss index, assuming the minimum
number of stable data points are recorded.
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NOTE:
Both panels will generally soil at the same rate. The soiling ratio is most important the day
after the reference panel is cleaned.
If zero stable data points are recorded during the previous day, the SLI will show NAN. If the
minimum number of stable data are recorded, the soiling loss indexes will update at midnight.
4.4 Modbus settings and data
The following table shows default Modbus settings for the DustVue. Any device querying
information from the DustVue must have the same settings in order to receive the information.
Table 4-2: Modbus configuration
Parameter Default setting
Comport Ethernet, port 502
Baud Rate Not applicable for Modbus TC/IP. Defined by connection speed.
Parity No parity
Modbus address 11
Data 32-bit, float
Data format CDAB
The Modbus data can be viewed in the Public table.
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5. Overview
The DustVue uses the comparison-of-short-circuit method for assessing solar module
performance and losses due to soiling. Numerous studies have compared the advantages and
disadvantages of the different methods used to calculate losses due to soiling. These studies
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