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The blower cannot take in solid material, dust or liquid.
Intake of them may cause an accident resulting in damage.
In the case of deceleration by an inverter, etc., a resonance between the main body and a duct
around it may cause an increase in vibration or generation of sound at a specific frequency
(rotation speed). In such a case, use the blower at a frequency other than that frequency. The
shipment inspection of this blower is performed only at the rated rotation speed*. This does
not mean that operation of the blower is guaranteed at frequencies other than that frequency.
* Operation inspection of special order products, parts, etc., may not be performed in some cases.
Precautions for the use of an inverter to operate the blower
(1)
The standard motor may not be used for the operation in some cases as shown below.
•
In the case that the insulation deteriorates due to surge voltage caused by the use of
a 400-V class motor whose insulation is not reinforced
•
In the case of no margin for temperature rise in the motor
•
In the case of no margin for allowable load GD2 of the motor
(2)
At factory shipment, the setting of a commercial inverter is not suitable for the blower.
Change the following values at least.
•
Base frequency:
Adjust to the rated frequency of the blower (50 Hz or 60
Hz).
•
Highest frequency:
Adjust to the rated frequency of the blower.
•
Maximum output voltage: Adjust to the rated voltage of the motor.
•
Upper-limit frequency:
Adjust to the rated frequency of the blower.
•
Lower-limit frequency:
25 to 30 Hz (based on the cooling characteristics of the
motor).
•
V/f characteristics:
Change to square reduction torque.
(3)
Other
precautions
•
The standard blower cannot be operated at an increased speed.
•
Vibrations of components (belt, casing, etc.) making up the blower may increase at a
specific frequency. If the increase in vibration cannot be eliminated even after other
set values are changed, a resonance point may be causing it. In such a case, set a
jump frequency to prevent the increase in frequency.
•
If the blower is installed on a vibration isolation table (rubber, spring, etc.), a
decrease in frequency may become a resonance frequency. In such a case, set the
jump frequency to prevent this symptom (otherwise, the blower and motor are
individually affected).
•
If the carrier frequency is set higher, current leakage may increase, and the earth
leakage breaker may be activated.
•
Do not use the inverter output power for applications other than electric motors
.
