Solar Irradiance Meter for Factory Rooftop PV Maintenance Malaysia
Solar Irradiance Meter for Factory Rooftop PV Maintenance Malaysia
Factory rooftop solar PV systems require more than visual inspection when maintenance teams investigate performance changes.
Electrical measurements tell technicians what the PV system is producing, but another question is equally important:
How much solar radiation is reaching the panels at the time of testing?
A solar irradiance meter measures incoming solar power in W/m² (watts per square metre) and provides useful environmental information during factory rooftop PV inspection.
For maintenance teams that require portable solar radiation measurement, the VICI LX-107 Solar Power Meter is one option for field use.
Why Factory Maintenance Teams Need Solar Irradiance Data
Imagine a factory engineering team notices that PV production appears lower than expected.
The first assumption might be:
“There is a problem with the solar panels.”
But lower electrical output alone does not identify the cause.
At the time of measurement, solar radiation could be reduced by:
Cloud cover
Haze
Temporary shading
Time of day
Roof orientation
Nearby structures
Changing weather conditions
Measuring solar irradiance provides an additional reference point before technicians proceed with deeper troubleshooting.
What Does W/m² Tell the Technician?
Solar irradiance is commonly measured in watts per square metre (W/m²).
This measurement describes the solar power incident on a surface.
For factory rooftop PV work:
W/m² tells you about the available solar radiation.
It does not directly tell you how much electricity the solar panel is producing.
That distinction is important.
A maintenance team can combine irradiance measurement with PV electrical measurements to understand the conditions under which the system is operating.
Solar Irradiance + Electrical Measurement
A useful inspection should avoid looking at one number in isolation.
For example:
Solar irradiance: ___ W/m²
DC voltage: ___ V
DC current: ___ A
Module temperature: ___ °C
Time: ___
Weather: ___
When these measurements are recorded together, the maintenance report becomes more meaningful.
Example 1 – Low Output and Low Irradiance
A technician investigates a factory rooftop PV array during cloudy conditions.
Electrical output appears low.
The solar irradiance reading also indicates weak incoming solar radiation.
This information tells the technician that environmental conditions must be considered when interpreting the PV output.
Low output under weak sunlight is not the same troubleshooting condition as low output under strong sunlight.
Example 2 – Strong Sunlight but Abnormal Performance
Now consider another inspection.
Solar irradiance is relatively strong, but the PV system still appears to be performing unexpectedly.
The maintenance team may then investigate additional factors such as:
Dirty modules
Partial shading
Module damage
Cable condition
Connector problems
PV string differences
Inverter conditions
Temperature effects
Other electrical issues
The irradiance meter does not diagnose these faults directly.
Its role is to establish the solar radiation condition during the test.
Common Factory Rooftop PV Maintenance Problems
Industrial rooftop solar systems operate in environments that may introduce additional maintenance challenges.
Dust and Dirt
Factories near construction areas, highways or industrial processes may experience contamination on PV module surfaces.
Bird Droppings
Localised contamination can create uneven shading on individual modules.
Rooftop Equipment
Water tanks, exhaust systems, ventilation equipment, antennas and other structures may produce shadows at certain times of day.
Changing Building Conditions
New equipment or structures installed after the original solar project may change shading patterns.
Cable and Connector Condition
Outdoor electrical components are exposed to heat, moisture and weather.
Module Temperature
High operating temperatures can influence PV performance and should be considered when carrying out more detailed analysis.
Solar irradiance is one part of this larger maintenance picture.
How to Measure Solar Irradiance on a Factory Roof
A practical field procedure can include the following steps.
Step 1 – Check the Weather
Record whether conditions are clear, cloudy or rapidly changing.
Step 2 – Select W/m²
Set the solar power meter to the required solar radiation measurement unit.
Step 3 – Position the Sensor
When assessing irradiance relevant to the PV modules, sensor orientation should correspond appropriately to the module plane.
Sensor angle is important when comparing readings.
Step 4 – Avoid Accidental Shading
Ensure the technician, safety equipment or nearby rooftop objects do not shade the sensor.
Step 5 – Record the Irradiance
Take the W/m² reading and record the time.
Step 6 – Take Related PV Measurements
Perform the relevant electrical or temperature measurements close to the irradiance measurement time.
Step 7 – Document the Results
Keep environmental and electrical readings together for easier comparison and future maintenance reference.
Why Measurement Timing Matters in Malaysia
Malaysia's tropical weather can produce rapidly changing sunlight conditions.
A rooftop may experience strong sunshine followed by cloud cover within a short period.
This means:
A solar irradiance reading taken at 10:00 AM should not automatically be assumed to represent conditions during a PV measurement taken much later.
For troubleshooting, take irradiance readings as close as practical to the corresponding PV measurements.
VICI LX-107 Solar Power Meter
The VICI LX-107 is a portable instrument for solar power measurement.
Its useful field functions include:
W/m² Measurement
For measuring solar power per unit area.
BTU Display
An additional measurement unit for relevant applications.
MAX / MIN
Useful for observing changes in solar radiation.
Data Hold
Allows a displayed reading to be held for easier recording.
The handheld format is useful when maintenance personnel need to move between multiple measurement locations across a factory rooftop.
Solar Irradiance Meter vs DC Clamp Meter
These instruments serve different purposes.
Solar Irradiance Meter
Measures incoming solar radiation.
DC Clamp Meter
Measures electrical current without requiring the same direct circuit connection method as a conventional current measurement.
A maintenance team may use both during appropriate PV inspection procedures.
One provides environmental information; the other provides electrical information.
Solar Irradiance Meter vs Thermal Camera
A thermal camera is another useful instrument for solar maintenance.
It can help technicians inspect temperature patterns and investigate potential hotspots or abnormal heating.
However:
Thermal camera → temperature distribution
Solar irradiance meter → incoming solar radiation
They are complementary instruments rather than substitutes.
Factory Solar Maintenance Instrument Checklist
Depending on the maintenance scope and system, an engineering team may require:
Solar irradiance meter
DC clamp meter
Digital multimeter
PV tester
Insulation resistance tester
Earth resistance tester
Thermal imaging camera
Temperature meter
Not every factory requires every instrument.
Equipment should be selected according to the actual maintenance procedure and PV system requirements.
Preventive Maintenance vs Troubleshooting
Solar irradiance measurement can support both activities.
Preventive Maintenance
Record environmental conditions during scheduled PV inspections and maintain more consistent records.
Troubleshooting
Measure irradiance when investigating unexpectedly low or inconsistent PV performance.
This is especially useful when technicians need to distinguish between changing sunlight conditions and potential equipment-related problems.
Who Can Use the VICI LX-107?
The LX-107 can be relevant for:
Factory Engineering Departments
For industrial rooftop solar inspection.
Facility Maintenance Teams
For scheduled PV maintenance.
Solar EPC Contractors
For installation and field testing.
PV O&M Companies
For operation and maintenance work.
Electrical Contractors
For solar-related electrical projects.
Energy Management Teams
For supporting solar performance investigations.
Portable Solar Irradiance Meter for Industrial Maintenance
For factory maintenance teams that need straightforward spot measurements, a portable instrument can be easier to deploy than a permanent monitoring system.
However, the two should not be confused.
A handheld solar irradiance meter is useful for field measurements and troubleshooting.
A permanent monitoring system is designed for continuous data collection.
The correct solution depends on the measurement objective.
VICI LX-107 Solar Power Meter Supplier Malaysia
MTM Precision supplies industrial testing and measurement instruments for factory maintenance, electrical testing, solar PV inspection and engineering applications in Malaysia.
The VICI LX-107 Solar Power Meter can support portable solar radiation measurements during factory rooftop PV inspection and maintenance.
MTM Precision can also assist customers in selecting other instruments required for broader solar and electrical maintenance applications.
Contact MTM Precision
MTM Precision Sdn Bhd
Website: www.mtmpre.com.my
Email: mtmpre@yahoo.com
WhatsApp: 016-660 7346
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia.
Serving industrial and engineering customers throughout Selangor, Kuala Lumpur, Johor, Penang, Perak, Negeri Sembilan, Melaka, Pahang, Kedah, Perlis, Terengganu, Kelantan, Sabah and Sarawak.
Maintaining a factory rooftop solar PV system? Contact MTM Precision for VICI LX-107 Solar Power Meter availability and suitable solar and electrical testing instruments.
08 Sep 2026
