Solar Traffic Sign Maintenance

Many road operators and traffic facility maintenance personnel have reported that after using solar-powered traffic signs for 1 to 2 years, problems such as "no light at night", "shortened battery life", and "abnormal LED flashing" often occur. In fact, 80% of these issues are due to a lack of scientific maintenance! Next, NOKIN will, based on years of professional experience, guide you step by step on how to carry out full-cycle maintenance - this can not only extend the lifespan of solar-powered traffic signs but also reduce road safety hazards and lower long-term replacement costs.
 

Solar LED Traffic Signs Working Principle

To do a good job in maintenance, one must first understand the "structural logic" of the equipment - knowing the function of each component, so as to accurately identify problems. The core components of solar-powered traffic signs include solar panels, controllers, batteries, LED light sources and sign panels, etc. The normal operation of solar-powered traffic signs cannot do without the cooperation and coordination of these components.
 

Energy collection during the day: When the photovoltaic panels are exposed to light of ≥ 20,000 lux (equivalent to the light at 10 a.m. on a sunny day), they start to convert into electrical energy.
 

Controller intelligent charging: After the electrical energy is stabilized by the controller, it is input into the battery for storage (for example, a 12V battery will automatically cut off power when charged to 13.8V to prevent overcharging).
 

Automatic power supply at night: When the evening light is less than 5000lux, the controller switches to "discharge mode", and the battery supplies power to the LED module until dawn the next day.
 

4 Principles for Maintaining Solar Powered Traffic Signs

Scientific maintenance is not something that can be done on a whim. It requires following four major principles to be both effective and safe.
 

4 Goals of Solar Traffic Signs Maintenance

The ultimate goal of maintenance is "cost reduction + safety guarantee", and the specific goals include:
 

• Maximize energy harvesting: Avoid a decrease in power generation due to dirty panels and ensure sufficient battery life at night (at least 8 hours).
• Extend battery life: Reduce battery wear and tear and avoid battery replacement every 2-3 years.
• Ensure the visibility of the sign: Guarantee that the brightness of the LED and the effect of the reflective film meet the standards to prevent traffic accidents caused by "unclear visibility".
• Ensure structural safety: Prevent equipment from toppling over due to rusting of supports and settlement of foundations (toppling over equipment by the roadside on expressways may cause traffic accidents).

4 Principles That Must be Adhered to

• Regular execution: Maintain at a fixed frequency of "monthly/quarterly/annual", such as "check battery voltage monthly and clean the panel quarterly", to prevent problem accumulation.
• Documented management: Each maintenance is recorded with "date, issue, and handling method" (template in Part 6), facilitating the traceability of fault causes.
• Adjust by season: Prevent sand and dust in spring, high temperatures in summer, fallen leaves in autumn, and snow accumulation in winter, and deal with environmental impacts in a targeted manner.
• Safety first, operation later: All electrical checks must be "de-energized" (turn off the power switch of the controller) before operation. Safety belts must be worn during high-altitude maintenance to prevent falls.

Reminder

When photovoltaic panels are covered with a thin layer of dust (with a thickness of less than 1mm), the power generation will decrease by 15% to 30%.

If there is bird droppings or oil stains (such as vehicle exhaust adhering), the power generation will decrease by 30% to 50%.

A 2-cm scratch appeared on the panel, causing the power generation to drop by 8% to 12%. In severe cases, it directly led to a shutdown at night.
 

Solar LED Traffic Signs Regular Maintenance List

Regular maintenance should be divided into key points by "month/quarter/year". The maintenance frequency and methods for different components vary, and they can be directly followed accordingly.
 

Solar Panel Cleaning

Panel cleaning is the "easiest to operate but most easily overlooked" step. Correct cleaning can increase power generation by more than 20%.
 

Key points of operation

• Use a soft-bristled brush (with a bristle length of ≥2cm, such as a car wash soft brush) to sweep away the surface dust.
• Wipe with a microfiber cloth (such as an eyeglass cloth) dipped in "neutral detergent dilution" (dishwashing liquid: water = 1:10).
• Finally, rinse thoroughly with a low-pressure water hose (water pressure less than 0.3MPa, equivalent to a medium-range household showerhead) to avoid leaving any detergent residue.

Strictly prohibited:

Flushing with a high-pressure water gun (water pressure > 1MPa) (which may damage the panel coating), scraping with steel wool balls/sandpaper (which may cause scratches), and using strong acid or alkali cleaners (such as toilet cleaner, which may corrode the panel).
 

Best time:

Early morning (6-8 a.m.) or evening (17:00-19:00), when the panel temperature is less than 40℃. Avoid the thermal expansion and contraction of the panel caused by cold water meeting high temperature (which may lead to glass cracking).
 

Frequency suggestion:

In areas with a lot of dust and dense bird droppings (such as near highway service areas and roads beside farmlands) : Once a month;

For ordinary urban roads and suburban roads: once every quarter.
 

Solar Traffic Signs Battery Inspection and Maintenance

Batteries are "consumables". Proper maintenance can extend their lifespan by 30%. The key points for inspection are as follows:
 

Mandatory items to check:

• Voltage detection: Use a digital multimeter to measure the battery voltage (normal voltage for a 12V battery: 13.5-13.8V when fully charged, and no less than 10.5V after discharge).
• Visual inspection: Check if there is patina (corrosion) on the terminals, if the battery is swollen (caused by overcharging), and if there is any leakage (if a sealed battery leaks, it is scrapped).
• Sealing inspection: For Gel/AGM batteries, it is necessary to check whether the exhaust valve is intact to prevent air leakage.

Replacement cycle (by battery type) :

Charging strategy:

Charge strictly in accordance with the manufacturer's parameters. For instance, for LiFePO4 batteries, the charging voltage should not exceed 14.2V and the discharge voltage should not be lower than 10V. Avoid prolonged deep discharge (such as when the battery is completely drained due to continuous rainy days).
 

Solar Traffic Signs Controller and Electrical Connection

The controller is the "brain" of the system. Loose electrical connections can lead to "inability to charge" and "lights not turning on". Key inspection points:
 

Must-check points:

• Controller display: Check if there is an "overvoltage/overcurrent/undervoltage" alarm on the screen (if it shows "E01", it may be overvoltage and needs to be powered off and restarted).
• Wiring inspection: Tighten all wiring screws (use a cross-head screwdriver to tighten them until they do not loosen with "slight force", and avoid breaking the wires).
• Inspection of the protective box: Check if the waterproof seal has aged (such as hardened or cracked), and whether there is condensation inside the box (desiccants should be placed in high-humidity areas).
• Lightning protection device: Check whether the lightning protection wire is firmly connected (in areas prone to thunderstorms, the lightning protection resistance should be measured annually, with a requirement of less than 10Ω).

Safety Tips:

Before all wiring checks, the power switch of the controller must be turned off to avoid electric shock.

In high-humidity areas (such as the rainy season in the south), open the protective box for ventilation once a month to prevent condensation from damaging the circuit board.
 

Solar Traffic Signs LED/Flicker Module and Reflective Panel

LED and reflective panels are the "warning core". If the effect does not meet the standards, it is equivalent to "equipment being installed in vain".
 

LED module inspection:

Brightness test: Stand 300 meters away at night and observe. The outline of the sign can be clearly seen (if not, the LED current needs to be measured. The normal current is 100mA-300mA).

Flashing frequency: According to traffic standards, the flashing frequency should be 60 to 90 times per minute (it can be timed with a mobile phone stopwatch. If the deviation exceeds 10 times per minute, the controller parameters need to be adjusted).
 

Reflective panel inspection:

Appearance: Check if the reflective film is damaged or fallen off (if the edge is lifted by more than 1cm, it needs to be replaced).

Fading test: Use a colorimeter to measure the color of the panel (such as the red mark. When the color difference value ΔE is greater than 5, the reflective film needs to be replaced).

Replacement suggestion: The service life of reflective film is usually 3 to 5 years (outdoors). Even if there is no damage, it is recommended to replace it after 5 years to avoid a decline in reflective effect at night.
 

Solar Traffic Signs Structural and Support Inspection

The support and foundation are the "skeleton". If they are damaged, it may cause the equipment to tip over.
 

Must-check points:

Support bolts: Use a wrench to check all bolts (such as M8 bolts, tighten until "no loosening with force of 10N·m"). Rusty bolts need to be replaced (it is recommended to use hot-dip galvanized bolts for anti-corrosion).

Foundation inspection: Check if there are any cracks in the concrete foundation (if the width is greater than 0.5mm, they need to be repaired) and if there is any settlement (if it becomes level with the ground but shows a "settlement of 2cm", reinforcement is required).

Collision marks: Check the panel and bracket for any vehicle scratch marks (if deformed, they need to be corrected or replaced to avoid affecting structural stability).
 

Emergency handling:

If any bending of the support or cracking of the foundation is detected, immediately set up a "warning cone" to prohibit vehicles from approaching and replace the damaged parts within 24 hours (such as temporarily using steel pipes for support to prevent toppling).
 

Common Faults and Troubleshooting Procedures

FAQ About Solar Traffic Signs Maintain

Q1: How much power generation will be affected if there is a thin layer of dust on the photovoltaic panel?

A: According to Optraffic's 2024 actual measurement:

• Thin dust (thickness < 1mm, such as ordinary dust) : Power generation decreases by 15%-30%;
• Thick dust + bird droppings (such as covering 1/3 of the panel) : Power generation decreases by 30%-50%;
• Oil pollution (such as adhesion from vehicle exhaust) : Power generation drops by 50% to 70%, and in severe cases, the system may shut down at night.

Q2: How often do the batteries of solar-powered traffic signs need to be replaced?

A: Classified by battery type, the replacement cycle under normal maintenance is:

• LiFePO4 (lithium iron phosphate) : 8-12 years, replace when capacity is less than 80%;
• Gel (colloid) : 6-8 years, replace when the volume is less than 75%;
• AGM: 5-7 years, replace when capacity is less than 70%;
• Deep-cycle lead-acid: Replace every 3 to 5 years when the capacity is less than 60%.

Q3: Water has entered the solar-powered traffic signs during the rainy season. How should it be dealt with?

A: Handle the emergency in three steps to avoid short circuits:

• Immediate power off: Turn off the power switch of the controller and unplug the battery wiring.
• Clear accumulated water: Use a dry towel to dry the accumulated water inside the protective box, and use a hair dryer (cold air) to dry the wiring interfaces (to avoid hot air damaging components).
• Inspection and replacement: Check if the sealing strip is aged (hardened or cracked). If it is aged, replace it immediately. Test whether the equipment is functioning properly (observe for 30 minutes after power-on; put it into use only if there are no abnormalities).

Q4: How to protect solar-powered traffic signs when they are damaged by humans (such as smashing the panels or cutting the wires)?

A: Four protective measures to reduce the rate of damage

• Install anti-theft bolts: Use "hexagon socket anti-theft bolts" for brackets and protective boxes (a special wrench is required to open them);
• Install surveillance: Install solar-powered surveillance cameras (with motion detection alarms) around the equipment to deter vandals.
• Increase installation height: Raise the equipment height from 2.5 meters to 3.5 meters to avoid easy contact.
• Select impact-resistant panels: Use "tempered glass + PC board" composite panels (with an impact resistance five times that of ordinary glass).

Q5: The power generation of solar traffic signs drops significantly in winter. How can this be solved?

A: 3 Practical Methods to Increase power Generation in Winter

• Adjust the panel's tilt Angle: Set it as "local latitude + 10°" (for example, at 30° north latitude, set the tilt Angle to 40°) to enhance the sunlight reception rate;
• Timely snow removal: Within 2 hours after snowfall, use a soft plastic shovel to clear the snow on the panels to prevent ice formation (ice formation can reduce power generation by 80%).
• Battery insulation: Cover the battery with an "IP65 grade insulation sleeve" (made of flame-retardant sponge material), which can increase the battery capacity by 20% to 30% at -10℃.