Mitsubishi Electric FR-D720-0.2K-G Instruction Manual page 20

(3) Dust, dirt, oil mist
Dust and dirt will cause such faults as poor contact of contact points, reduced insulation or reduced cooling effect due to
moisture absorption of accumulated dust and dirt, and in-enclosure temperature rise due to clogged filter. In the atmosphere
where conductive powder floats, dust and dirt will cause such faults as malfunction, deteriorated insulation and short circuit in
a short time.
Since oil mist will cause similar conditions, it is necessary to take adequate measures.
Countermeasures
 Place in a totally enclosed enclosure.
Take measures if the in-enclosure temperature rises. (Refer to page 10.)
 Purge air.
Pump clean air from outside to make the in-enclosure pressure higher than the outside-air pressure.
(4) Corrosive gas, salt damage
If the drive unit is exposed to corrosive gas or to salt near a beach, the printed board patterns and parts will corrode or the
relays and switches will result in poor contact.
In such places, take the measures given in Section 3.
(5) Explosive, flammable gases
As the drive unit is non-explosion proof, it must be contained in an explosion proof enclosure. In places where explosion may
be caused by explosive gas, dust or dirt, an enclosure cannot be used unless it structurally complies with the guidelines and
has passed the specified tests. This makes the enclosure itself expensive (including the test charges). The best way is to
avoid installation in such places and install the drive unit in a non-hazardous place.
(6) Highland
Use the drive unit at the altitude of within 1000m. If it is used at a higher place, it is likely that thin air will reduce the cooling
effect and low air pressure will deteriorate dielectric strength.
(7) Vibration, impact
The vibration resistance of the drive unit is up to 5.9m/s
Y, Z axes. Vibration or impact, if less than the specified value, applied for a long time may make the mechanism loose or
cause poor contact to the connectors.
Especially when impact is imposed repeatedly, caution must be taken as the part pins are likely to break.
Countermeasures
 Provide the panel with rubber vibration isolators.
 Strengthen the structure to prevent the enclosure from resonance.
 Install the enclosure away from sources of vibration.
Installation of the drive unit and enclosure design
2
at 10 to 55Hz frequency and 1mm amplitude for the directions of X,
1
9