1, press the start switch electric hoist does not work

Mainly due to the hoist not connected to the rated working voltage, and can not work, there are generally three kinds of situations:

(A) whether the power supply system for electric hoist power transmission, usually with test pencil tests, such as no power transmission, power transmission, etc. after work; (2) the main hoist, electrical damage to the control circuit, the line is disconnected or bad, also make the hoist motor can not be energized, such a situation, the need to repair the main, the control loop, maintenance, in order to prevent the main, three-phase motor control circuit to give power to the motor phase and burned, or hoist motor suddenly energized operation, cause harm, be sure to hoist the motor is disconnected from the power line, only to master, control circuit power transmission, and then move the start and stop switches, electrical control and circuit inspection and analysis of the work, or to have the problem of electrical lines repair or replacement, when the confirmation Lord, the control circuit trouble, before re-commissioning; (3) hoist motor terminal voltage is lower than the rated voltage of more than 10%, motor starting torque is too small, so do not move goods lifting hoists, and unable to work , check with a multimeter or voltage meter and other measuring motor input voltage, indeed due to low voltage, so that the motor can not be started, the need to wait for the system voltage returns to normal before using electric hoist. Sometimes, hoist motor voltage is normal, while the hoist is not working, it should be considered for other reasons, for example: motor is burned, overhaul need to replace the motor; gourd unused for long periods, poor maintenance, the brake wheel and cover rust, brake wheel when starting off is not open, the motor only issued a "hum" sound, turn it up, Hulu does not work. At this time, you should remove the brake wheel, cleaning corroded surfaces, and then re-test; serious motor sweep chamber, but also make the motor does not rotate, found this situation, you should stop using the motor must be overhauled or replaced in order to ensure the normal hoist work. In addition, the production of non-overloading using electric hoist, when the goods are excessively overloaded, hoist crane does not move goods, the motor will only issue a "hum" sound, rather than running, and in severe burning motor, or even cause an accident, this time should be immediately shut down, reduce cargo, the gourd work at rated power.

2, electric hoist abnormal noise when running

Many electric hoist failure, such as control of electrical appliances, motor or reducer failures, often accompanied by abnormal noise, the noise level of the position and not with the cause of the malfunction and sound different and have different, overhaul, to see and hear more, You can use the sound characteristics according to the fault or determine beep location, locate and repair faults.

(1) abnormal noises occur in the control loop, issued a "hum" noise, usually contactor malfunction (such as AC contactor contacts being exposed, the voltage level does not match, the core was stuck, etc.) to deal with fault contact with device for repair, you can not repair must be replaced after processing, self-noise elimination.

(2) motor makes any abnormal noise, immediately stop and check whether the motor running single phase, or bearing damage, coupling axis errors and "sweep chamber" faults, these will make the motor abnormal sound, the sound of a different fault location and the level and tone a difference, single-phase operation, the entire motor makes regular suddenly strong suddenly weak "buzzing" sound; while the bearing is damaged when the bearing near the issue along with the "thump - thump" of the "buzz" sound; while coupling axis errors, or when the motor slight sweep chamber, the entire motor makes high "buzzing" sound, not when accompanied by a shrill voice. In short, the difference should be based on the noise, to find fault, for itemized repair and restore normal performance of the motor when the motor fault untreated, prohibit the use of gourds.

(3) abnormal noises issuing from the reducer, reducer failure (such as lack of lubrication or bearing gearbox, gear wear or damage, bearing damage, etc.), then should stop to check, first determine the reducer gearbox or bearing added prior to use lubricating oil, lubricating oil use is changed regularly, if not required lubrication, reducer will not only generate excessive "buzzing" sound, but also excessive wear or damage to the gears and bearings. Some people think that being without reducer or just add a little oil, can still operate without catastrophic failure, this idea is wrong. I installed an electric hoist units, but had forgotten to give workers inject lubricant inside the gear unit, just one-day trial, which emit high noise reducer, gear box open and found the gear due to excessive wear and scrapped. Reducer bearing damage, and motor bearing failure similar, also in the vicinity of the bearing an abnormal sound. In order to prevent the failure to expand, either excessive wear or damage to the gear reducer or gearbox bearing damage, need to repair or replace the demolished immediately, eliminate the fault and reduce noise.

3, fell down when braking distance exceeds requirements

Electric hoist long-term disabled, someone mistakenly adjust the brake adjusting nut, or the brake ring wear is too large, the brake spring pressure decreases, the braking force is reduced, when the stop, the brake is not reliable, fell over a distance requirements, This situation just press gourd specification requirements, re-adjust the brake nut. But the work should pay attention to, lifting heavy objects, the prohibition adjustment, inspection and maintenance of the brake. Sometimes, adjusting the brake nut, stop down from the still exceeds the requirements, encountered such a situation, it is necessary to consider other reasons, first unpack the brake ring, check whether the brake surface sticky oil, such as a sticky oil , the friction coefficient is reduced, would braking skid, fall distance exceeds the requirements, adjust the brake nut only limited usefulness, then only thoroughly clean the braking surface (cleaning use benzine) to restore the braking surface friction coefficient ; Secondly, if the brake ring, loose or damaged brake ring can not guarantee efficient braking, only the replacement brake ring; sometimes found brake ring is not damaged, only the brake ring and end cap cone poor contact when braking , too little contact with the braking surface, the braking force is too small, the decline over a distance requirements, maintenance, in order to increase the braking force, should find out the position of poor contact, for grinding, increasing the contact surface when braking, not grinding, you need replacement parts; hoist motor coupling ran ineffective or stuck, after the shutdown, the brake cone ring and end cap is bad or not accessible, so that the braking effect gourd good times and bad, such situations, coping couplings for repair or replacement. In addition, long-term use of the brake pressure spring fatigue, so that the spring force becomes smaller, stop, the brake is not solid, you should replace the spring, re-adjust the braking force.

4, the motor temperature is too high

Should first check the hoist is overloaded with overloading the motor heat, long-term overload the motor will burn; motor is not overloaded, still hot, you should check whether the motor bearing damage; should also check whether the motor is required duty work, which is caused by the motor heat One of the reasons, should be used in strict accordance with the motor duty work. The motor is running, the brake gap is too small, not fully disengaged, have a great friction, friction heat, while also representing an increase of additional load, the motor speed is reduced, the current becomes large fever, you should stop working, re- Adjust brake clearance.

5, the weight rose to the air, can not re-start after stopping

Analysis of the reasons, first check the system voltage is too low or fluctuating too large, the case of such a situation, only the other voltage returns to normal after the start; hand, we should pay attention to the three-phase motor operation phase, after the shutdown can not be started, At this point you need to check the power phases.

6, you can not stop or to limit position remains Parking

Such situation is generally contactor contact welding, press the stop switch when the contactor contacts can not be disconnected, the motor running as usual energized, hoist without stopping; into extreme positions such as limit malfunction, Hulu does not Parking. This happens, immediately cut off the power, the gourd forcibly stop. After stopping, repair contactors or stopper, serious damage can not be repaired and must be replaced.

7, gearbox oil spill

Reducer oil spill reasons are: (1) between the gear unit housing and cover, seal assembly is bad or invalid damaged, repair or replace the seals should be removed; (2) Reducer link screw not tightened, after the shutdown should tighten the screws.

8, the motor sweep chamber

Generate sweep chamber reasons are: the motor shaft bearing rings badly worn rotor core displacement, or because of other causes displacement of the stator core, causing the motor rotor and stator gap is too small conical occur sweep chamber. Motor prohibited "sweep chamber", when a sweep chamber, the support ring should be removed for replacement, adjust the gap between the stator and rotor cone so that uniform, or to a repair factory for repair. Through the electric hoist common faults and analysis, so that maintenance personnel to deal with failure gourd know where to start checking, improve maintenance efficiency, in addition, it provides the operator with a live approach to problems.