The characteristics of explosion-proof motors compared with ordinary motors are:
(1) Satisfy the requirements of the increased safety explosion-proof motor and adopt a series of measures to reliably prevent sparks, arcs and dangerous high temperatures, and can safely operate in explosion hazardous locations in Zone 2.
(2) Adopt brushless excitation, set the rotary rectifier plate and static excitation cabinet, the excitation control system is reliable; the polarity deviation and the excitation excitation are accurate, no impact; the excitation system is out of step protection is reliable, and the whole step ability is strong; the circuit design is reasonable The discharge resistor does not generate heat during operation; the excitation current regulation range is wide.
(3) Synchronous machine, AC exciter and rotating rectifier plate coaxial. The commutator disk is located between the main motor and the exciter, or outside the housing.
(4) The enclosure protection class is IP54.
(5) Class F insulation is used, and temperature rise is assessed according to Class B.
(6) Change the traditional water cooling to the upper water cooling, that is, the water cooler is placed on the upper part of the motor.
(7) An increased-safety type moisture-proof heater is fixed in the hood at the bottom of the motor and is used for heating and moisture-proof at the time of shutdown.
(8) Select high-quality raw materials, electrical and mechanical calculations to leave a larger margin, to meet the operating reliability and increased safety requirements of the temperature of the motor.
(9) Complete monitoring measures are provided; Increased-safety self-balanced current transformers for differential protection are installed in the main terminal box; Pt thermal resistances for stator winding work and spares are provided; the index number is Pt100; The instrument monitors the leakage of the water cooler; the two-piece seated sliding bearings are equipped with on-site temperature display instruments and remote signal terminals, respectively.