Installation of the inverter and enclosure design
When designing or manufacturing an inverter enclosure, determine the structure, size, and device layout of the enclosure by
fully considering the conditions such as heat generation of the contained devices and the operating environment. An inverter
unit uses many semiconductor devices. To ensure higher reliability and long period of operation, operate the inverter in the
ambient environment that completely satisfies the equipment specifications.
Inverter installation environment
The following table lists the standard specifications of the inverter installation environment. Using the inverter in an environment
that does not satisfy the conditions deteriorates the performance, shortens the life, and causes a failure. Refer to the following
points, and take adequate measures.
Standard environmental specifications of the inverter
-10 to +40°C (non-freezing)
With circuit board coating (conforming to class 3C2/3S2 in IEC 60721-3-3): 95% RH or less (non-condensing)
-20 to +65°C
Indoors (free from corrosive gas, flammable gas, oil mist, dust and dirt)
2500 m or lower
-40 to 50°C (non-freezing) at the rated current reduced by 15%.
Temperature applicable for a short time, for example, in transit.
For the installation at an altitude above 1000 m, consider a 3% reduction in the rated current per 500 m increase in altitude.
The permissible surrounding air temperature of the inverter is between -10 and +40°C. Always operate the inverter within this
temperature range. Operation outside this range will considerably shorten the service lives of the semiconductors, parts,
capacitors and others. Take the following measures to keep the surrounding air temperature of the inverter within the specified
Measures against high temperature
• Use a forced ventilation system or similar cooling system. (Refer to
• Install the enclosure in an air-conditioned electric chamber.
• Block direct sunlight.
• Provide a shield or similar plate to avoid direct exposure to the radiated heat and wind of a heat source.
• Ventilate the area around the enclosure well.
Measures against low temperature
• Provide a space heater in the enclosure.
• Do not power OFF the inverter. (Keep the start signal of the inverter OFF.)
Sudden temperature changes
• Select an installation place where temperature does not change suddenly.
• Avoid installing the inverter near the air outlet of an air conditioner.
• If temperature changes are caused by opening/closing of a door, install the inverter away from the door.
• For the amount of heat generated by the inverter unit, refer to
or less at 10 to 55 Hz (directions of X, Y, Z axes)
2. INSTALLATION AND WIRING
2.3 Installation of the inverter and enclosure design