Hitachi X200 manual For Correct Operation, Application to Motors

For Correct Operation

Application to Motors

Application to general-purpose motors

Operating frequency	The overspeed endurance of a general-purpose motor is 120% of the rated speed for 2 minutes (JIS C4,004). For operation at higher
	than 60Hz, it is required to examine the allowable torque of the motor, useful life of bearings, noise, vibration, etc. In this case, be
	sure to consult the motor manufacturer as the maximum allowable rpm differs depending on the motor capacity, etc.
Torque characteristics	The torque characteristics of driving a general-purpose motor with an inverter differ from those of driving it using commercial power
	(starting torque decreases in particular). Carefully check the load torque characteristic of a connected machine and the driving torque
	characteristic of the motor.
Motor loss and	The torque characteristics of driving a general-purpose motor with an inverter differ from those of driving it using commercial power
temperature increase
Noise	When run by an inverter, a general-purpose motor generates noise slightly greater than with commercial power.
	When run by an inverter at variable speeds, the motor may generate vibration, especially because of (a) unbalance of the rotor
Vibration	including a connected machine, or (b) resonance caused by the natural vibration frequency of a mechanical system. Particularly, be
	careful of (b) when operating at variable speeds a machine previously fitted with a constant speed motor. Vibration can be minimized
	by (1) avoiding resonance points using the frequency jump function of the inverter, (2) using a tire-shaped coupling, or (3) placing a
	rubber shock absorber beneath the motor base.
Power transmission	Under continued, low-speed operation, oil lubrication can deteriorate in a power transmission mechanism with an oil-type gear box
	(gear motor) or reducer. Check with the motor manufacturer for the permissible range of continuous speed. To operate at more than
mechanism
	60Hz, confirm the machine , s ability to withstand the centrifugal force generated.
Application to special motors
Gear motor	The allowable rotation range of continuous drive varies depending on the lubrication method or motor manufacturer.
	(Particularly in case of oil lubrication, pay attention to the low frequency range.)
Brake-equipped motor	For use of a brake-equipped motor, be sure to connect the braking power supply from the primary side of the inverter.
Pole-change motor	There are different kinds of pole-change motors (constant output characteristic type, constant torque characteristic type, etc.), with
	different rated current values. In motor selection, check the maximum allowable current for each motor of a different pole count. At
	the time of pole changing, be sure to stop the motor. Also see: Application to the 400V-class motor.
Submersible motor	The rated current of a submersible motor is significantly larger than that of the general-purpose motor. In inverter selection, be sure
	to check the rated current of the motor.
Explosion-proof motor	Inverter drive is not suitable for a safety-enhanced explosion-proof type motor. The inverter should be used in combination with a
	pressure-proof explosion-proof type of motor.
	*Explosion-proof verification is not available for X200 Series.
Synchronous (MS) motor	In most cases, the synchronous (MS) motor and the high-speed (HFM) motor are designed and manufactured to meet the
High-speed (HFM) motor	specifications suitable for a connected machine. As to proper inverter selection, consult the manufacturer.
Single-phase motor	A single-phase motor is not suitable for variable-speed operation by an inverter drive. Therefore, use a three-phase motor.

Application to the 400V-class motor

A system applying a voltage-type PWM inverter with IGBT may have surge voltage at the motor terminals resulting from the cable constants including the cable length and the cable laying method. Depending on the surge current magnification, the motor coil insulation may be degraded. In particular, when a 400V-class motor is used, a longer cable is used, and critical loss can occur, take the following countermeasures:

(1)install the LCR filter between the inverter and the motor,

(2)install the AC reactor between the inverter and the motor, or

(3)enhance the insulation of the motor coil.

Notes on Use

Drive

Run/Stop	Run or stop of the inverter must be done with the keys on the operator panel or through the control circuit terminal. Do not operate by
	installing a electromagnetic contactor (MC) in the main circuit.
Emergency motor stop	When the protective function is operating or the power supply stops, the motor enters the free run stop state. When an emergency
	stop is required or when the motor should be kept stopped, use of a mechanical brake should be considered.
	A max. 400Hz can be selected on the X200 Series. However, a two-pole motor can attain up to approx. 24,000 rpm, which is
High-frequency run	extremely dangerous. Therefore, carefully make selection and settings by checking the mechanical strength of the motor and
	connected machines. Consult the motor manufacturer when it is necessary to drive a standard (general-purpose) motor above 60Hz.
	A full line of high-speed motors is available from Hitachi.

Installation location and operating environment

Avoid installation in areas of high temperature, excessive humidity, or where moisture can easily collect, as well as areas that are dusty, subject to corrosive gasses, mist of liquid for grinding, or salt. Install the inverter away from direct sunlight in a well-ventilated room that is free of vibration. The inverter can be operated in the ambient temperature range from -10 to 50˚C.(Carrier frequency and output current must be reduced in the range of 40 to 50˚C.)

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