How to Install a Rainproof LED Power Supply Safely
Short answer
A Rainproof Led Power Supply must be installed in the correct orientation, with its wiring terminals facing downward, protected electrical connections and enough open space for ventilation. It isRainproof, not Waterproof, so it must not be placed where water can enter the housing or collect around the terminals.
Installation should be completed by a qualified electrician. Always follow the exact product label and approved model instructions.
Before installation
- Confirm that the LED load voltage matches the power-supply output voltage.
- Confirm that the calculated LED load is within the approved capacity of the selected model.
- Check that the input supply matches the voltage and frequency shown on the exact product label.
- Choose a location protected from direct water entry and standing water.
- Provide enough space for ventilation and future inspection.
- Disconnect the power before work begins.
Do not rely on a family name or website description when the exact model label gives different information. Ask MIJI to resolve any unclear or conflicting value before installation.
1. Mount the power supply vertically
Install the Rainproof Power Supply vertically with the wiring terminals facing downward. This orientation helps reduce the possibility of rainwater reaching the terminal area or entering through the enclosure openings.
Do not mount the unit with the terminals facing upward. Do not place it flat in a location where water can collect.
2. Maintain ventilation clearance
The current JT source instructions specify:
- at least 10 cm of clearance on the top, bottom, left and right sides;
- at least 5 cm of clearance from the ventilation-hole side.
Do not block ventilation openings with insulation, cable bundles, packaging material or the wall of a tightly enclosed box. Ambient temperature, connected load and cabinet airflow must be considered together.
3. Protect the terminals and cable entry
Rainproof does not mean that exposed terminals or cable joints may be left in direct rain.
- Keep the terminal side facing downward.
- Use suitable cable entry and connection protection for the installation environment.
- Prevent water from following a cable into the terminal area.
- Keep input and output wiring organized and separated where required.
- Do not leave bare conductors or loose terminals.
If the installation may be exposed to standing water, temporary immersion or uncontrolled water entry, stop and select a product and enclosure arrangement approved for those conditions.
4. Follow the wiring diagram on the exact model
The product label is the primary wiring reference. Common markings may include:
- L: AC live
- N: AC neutral
- E or earth symbol: protective earth, where provided
- V+ or +: positive DC output
- V− or −: negative DC output
Do not energize the unit until a qualified electrician has checked the input, output, polarity, earth connection where applicable and terminal tightness. Never assume that every model uses an identical terminal arrangement.
5. Check the LED load before power-on
- The LED voltage must match the power-supply output.
- The total load and engineering margin must be approved.
- Cable length and voltage drop must be considered.
- No short circuit or reversed polarity may be present.
- The selected wire and connection method must suit the project.
A higher-wattage power supply is not automatically the correct choice if the voltage, installation or wiring is wrong.
6. Complete a pre-power inspection
- Confirm that the power supply is firmly mounted.
- Check that terminals face downward.
- Verify the required ventilation space.
- Inspect all connections and insulation.
- Confirm that water cannot enter the terminal or cable-entry area.
- Remove tools, loose wire strands and installation debris.
- Confirm that the connected load matches the approved design.
Power on only after the installation has passed the project’s electrical and safety checks.
7. Inspect the installation during service
Periodically check for blocked ventilation openings, loose or corroded terminals, damaged cable protection, water marks, unusual heat, noise, smell or unstable LED operation.
Disconnect power and arrange qualified inspection if abnormal conditions appear. Do not open or repair the power supply while it is energized.
Additional considerations for hot and dusty locations
For signage projects in hot or dusty environments, do not judge suitability from the word “outdoor” alone. Review the expected ambient temperature, solar heating, enclosure ventilation, dust accumulation, operating hours and connected load.
Where these conditions cannot be controlled, provide the installation drawing and environmental details to MIJI before selecting a JT Rainproof or DM Waterproof model.
Frequently asked questions
Can a Rainproof power supply be installed in direct rain?
Rainproof products still require the approved mounting orientation, protected terminals and controlled water exposure. They must not be treated as Waterproof products.
Can a JT Rainproof power supply be submerged?
No. JT must not be selected for immersion or standing-water conditions.
Why must the terminals face downward?
The downward orientation helps reduce the risk of water reaching the wiring and enclosure entry area. The exact product instructions remain controlling.
How much ventilation space is required?
The current source instructions specify 10 cm on four sides and 5 cm from the ventilation-hole side. Confirm these values for the exact model.
Can I install the power supply myself?
Installation should be completed by a qualified electrician who follows the product label, approved instructions and applicable local electrical requirements.
Need installation support? Send MIJI the model, LED load, installation drawing, environmental conditions and destination market.