Malfunctions Of An Angle Grinder And How To Fix Them

Possible malfunctions and ways to eliminate them Possible malfunctions and ways to eliminate them Closing timing and state of the main contacts The timing of closing the main contacts can be eliminated by tightening the clamp,

Possible malfunctions and solutions

Closing timing and state of main contacts

The timing of the closure of the main contacts can be eliminated by tightening the clamp holding the main contacts on the shaft. If there are traces of oxidation, sagging or frozen metal drops on the contacts, the contacts must be cleaned.

Strong hum of the magnetic system of the electromagnetic starter

Strong humming of the magnetic system can damage the starter coils. During normal operation, the starter emits only a faint noise. A strong hum of the starter indicates a malfunction.

To eliminate humming, the starter must be turned off and checked:

A) tightening the screws securing the armature and core,

B) whether the short-circuited turn, laid in the cuts of the core, is not damaged. Since an alternating current flows through the coil, the magnetic flux also changes its direction and at some points in time becomes equal to zero. In this case, the opposing spring will pull the armature away from the core and armature bounce will occur. A short-circuited loop eliminates this phenomenon.

C) the smoothness of the contact surface of both halves of the electromagnetic system of the starter and the accuracy of their fitting, since in electromagnetic starters the current in the winding strongly depends on the position of the armature. If there is a gap between the armature and the core, the current passing through the coil is greater than the rated one.

To check the accuracy of the contact between the armature and the core of the electromagnetic starter, you can put a sheet of carbon paper and a sheet of thin white paper between them and close the starter by hand. The contact surface must be at least 70% of the cross section of the magnetic circuit. With a smaller contact surface, this defect can be eliminated by correctly installing the core of the starter’s electromagnetic system. If a common gap has formed, then it is necessary to scrape the surface along the layers of the sheet steel of the magnetic system.

Lack of reverse in reversible magnetic starters

The lack of reverse in reversing starters can be eliminated by adjusting the mechanical interlock rods

Sticking of the armature to the core occurs as a result of the absence of a non-magnetic spacer or its insufficient thickness. The starter may not trip even if the coil voltage is completely removed. Check for presence and thickness of non-magnetic gasket or air gap.

It is necessary to check the condition of the starter interlocking contacts. The contacts in the on position must fit tightly to each other and turn on simultaneously with the main contacts of the starter. The clearances of auxiliary contacts (the shortest distance between an open moving and fixed contact) must not exceed the permissible values. It is necessary to adjust the auxiliary contacts of the starter. If the failure of the auxiliary contact becomes less than 2 mm, then the auxiliary contacts must be replaced.

Timely testing and adjustment of electromagnetic starters helps prevent malfunctions and damage in advance.

Typical malfunctions of magnetic starters, probable causes of these malfunctions, and methods for their elimination are shown in the table:

I. Starter does not turn on

  • The coil of the contactor is damaged (switching starter for PVI-32) The fuse in the control circuit is blown
  • Overcurrent protection has tripped. Signal lamp with red filter is on
  • The power contacts of the contactor touch the walls of the arcing chambers (except PVV-320)
  • Defective Start button
  • Broken diode in push-button
  • The wires are damaged.
  • Control (break, short
  • Some closure), increasing
  • Circuit resistance
  • Control over 20 Ohm
  • Insulation between conductors
  • Remote control below 300 ohms (cable pinched)
  • Malfunction in the control unit
  • Determine and eliminate the cause of the protection operation
  • Adjust the position of the moving contacts
  • Check the button and fix the problem
  • Switch to serviceable cable cores or replace the cable Measure the resistance of the control circuit, strip the contacts and tighten the fasteners at the electrical connections, replace the cable if necessary
  • Measure the insulation resistance between the cores and, if necessary, replace the cable
  • Replace the defective unit with a backup

2. The starter turns on, but does not stay on when the Start button is released

  • There is no circuit bridging the clamps of the Start button Malfunction of the RCU unit
  • Check for continuity and repair. Replace block
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3. When pressing the BRU or BKI button, the signal lamp does not light

  • Violation of the circuit in the button Check BRU or Check BKI. Warning lamp burned out. Malfunction inside the unit
  • Check button circuit and repair. Replace lamp. Replace control unit

4. The circuit breaker does not turn on (only for PVI-32)

  • Circuit breaker defective

5. The starter turns on and immediately turns off under the influence of overcurrent protection, the signal lamp with a red filter lights up

  • Short circuit in the protected power circuit Inconsistency of the setting of the overcurrent protection with the inrush current. Malfunction of the UMP or PMZ protection unit
  • Determine the location of the short circuit and repair the damage. Check the protection setting and adjust it to match the starting current. Replace block.

6. When the overcurrent protection or overload protection is triggered, the signal lamp does not light up

  • Signal lamp burned out

7. The starter shuts down spontaneously, it cannot be turned on again

  • Breakage or increase in the resistance of the remote shutdown circuit over 100 Ohm or decrease in the insulation resistance between the control conductors (the cable is pinched) Increase in the resistance of the grounding circuit over 50 Ohm (for PV-1140-250 starters)
  • Measure the resistance of the control circuit, clean the contacts and tighten the fasteners at the electrical connections. If necessary, switch to reserve wires or replace the cable

8. The starter hums strongly

  • The armature of the contactor does not fit tightly to the core due to: contamination damage to the skew poor fixing of the armature and the core large pressing of the contacts damage on the short-circuited loop of the low voltage network
  • Remove grease and dust. Eliminate damage. Eliminate the skew. Secure the anchor and core. Adjust the pressure of the power contacts. Replace the coil. Check the mains voltage and bring it in line with standards

9. Excessive heating of the power circuit contacts

  • Insufficient contact force
  • Excessive contact wear
  • Adjust contact pressure Check contact wear and replace if necessary

10. Excessive heating of the entire starter

  • Pantograph does not match the starter
  • Screws, nuts fastening live parts are loose
  • Replace the starter according to the load of the pantograph Tighten the fasteners

11. No voltage 36 V in the power circuit of the local lighting fixture (automation system)

  • The fuse in the lighting (automation) circuit of the secondary winding of the starter’s step-down transformer has blown

12. When the starter is turned on

  • Malfunction in the contactor closing force system Excessive or weakened pressing of the power contacts Low voltage in the network at the moment of closing the contactor power contacts
  • (for starters PVI-1140)
  • Adjust contact pressure. Measure the voltage and take measures to ensure the rated voltage value at the starter clamps Check the operation of the contactor forcing system

Topas malfunctions, their causes and remedies

Even a reliable wastewater treatment system like Topas can fail. In most cases, the cause of a system malfunction is non-compliance with the requirements of operation and untimely maintenance.

Often, hygienic and kitchen waste, plastic bags, solutions of caustic synthetic agents get into the wastewater treatment system. Such waste, in accordance with the operating rules of the Topas septic tank, should not enter wastewater, since the system cannot cope with their processing and disposal. Failure to comply with these requirements leads to clogging of the septic tank, and, as a result, to failure.

Often, the cause of a septic tank malfunction is a banal power outage, which leads to its overflow. Below are the main possible Topas malfunctions, their causes and remedies.

1. Unpleasant smell from the septic tank, or the exit from it of dirty water with an unpleasant odor.

The cause of this malfunction may be untimely maintenance of the septic tank, as well as a breakdown of the working sensor or pump airlift in the receiving chamber. In this case, it is necessary to flush and clean the system or replace the sensor.

2. There is a knockout of the septic tank protective shutdown device.

In this case, it is necessary to check the working sensor, drain pump and compressor, inspect the integrity of the wiring and, if necessary, repair or replace it.

3. Flooding of the septic tank. Possible causes of this problem:

  • The drain pump has failed (replace it if necessary);
  • The airlift of the main pump does not work (check the airlift, the membrane of the compressor, injectors, the float switch, clean or replace them);
  • In winter, the cause of this problem may be freezing of the outlet pipe (check its installation and reinstall if necessary).

4. Leakage of water from the septic tank or the flow of water into it when it is turned off.

In this case, it is necessary to make a visual inspection of the plumbing for leaks, if necessary, replace it or fix the leak. If the body of the station is damaged, call a specialist.

To prevent malfunctions of the Topas septic tank, the following work must be performed regularly:

  • It is necessary to clean the coarse filter every month, in which there is an accumulation of large waste that has entered the drainage system.
  • Clean the device for collecting non-recyclable particles 3-4 times a year.
  • Replace the compressor membranes once every 1.5-2 years.
  • Remove sludge from the sludge pond once every 3-4 months using a standard airlift pump. The frequency of this operation can be reduced to once every 6 months by cleaning with a drain pump.
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Regular maintenance of the Topas septic tank avoids situations leading to system malfunctions and the need for expensive repairs.

The main malfunctions of batteries, methods of their elimination

Since many people do not understand what kind of care the batteries require, breakdowns occur and the service life is significantly reduced.

The symptoms of battery failure are extensive and varied, so it is sometimes difficult to determine the real cause of failure.

The main types of faults

The most common reasons a battery becomes faulty are:

  1. The plates are destroyed.
  2. A short circuit occurs.
  3. Sulfation.
  4. Dirty electrolyte.
  5. Continuous battery discharge.
  6. Overdrive.

Methods for eliminating such breakdowns are difficult to carry out independently, therefore, specialized stations are engaged in their repair.

If you do not know the features of the repair, then a faulty battery can harm human health, which repairs it. The main malfunctions are presented and you need to familiarize yourself in detail, why they appear, how you can eliminate them.


A similar sign of a malfunction indicates the elimination of the battery, because the equipment will no longer work normally, and there is no way to restore the ABK. The problem appears during long-term storage with a discharge of the battery, as well as with constant discharge during operation.

The malfunction is provoked by a lack of electrolyte, when the plates are in contact with air all the time. In some cases, the problem appears when the density of the electrolyte is high, its temperature is high. The main features include:

  1. Very small capacity.
  2. Fast discharge.
  3. The battery gets very hot during charging.
  4. Many gases are emitted during charging.
  5. Charging takes a long time.

If such symptoms persist, the battery can be disposed of. This solution will be safe for the car owner.


A similar sign of a malfunction indicates the elimination of the battery, because the equipment will no longer work normally, and there is no way to restore the ABK. The problem appears during long-term storage with a discharge of the battery, as well as with constant discharge during operation.

The malfunction is provoked by a lack of electrolyte, when the plates are in contact with air all the time. In some cases, the problem appears when the density of the electrolyte is high, its temperature is high. The main features include:

  1. Very small capacity.
  2. Fast discharge.
  3. The battery gets very hot during charging.
  4. Many gases are emitted during charging.
  5. Charging takes a long time.

If such symptoms persist, the battery can be disposed of. This solution will be safe for the car owner.


malfunctions of an angle grinder and how to fix them

In most cases, the defect of reversing the battery can be eliminated

The malfunction consists in the incorrect switching on of the device, after which the poles on the battery change. If the malfunction is such, then you can fix the breakdown several times by charging and discharging the battery. Thus, the capacity will be restored and the battery can be used again.

In some cases, the malfunctions are so serious that the battery is only suitable for disposal.

The above are the main malfunctions of batteries, but there may still be cracks in the lids, tanks and other parts. They appear from mechanical damage, shock during use. Such malfunctions can be detected by visual inspection or by electrolyte leakage. In the presence of cracks, the battery cannot hold a charge for a long time, therefore it constantly discharges.


Many battery failures result from improper use and maintenance. A very important point is the service after the purchase, the first MOT.

So that breakdowns do not constantly pursue the owner, you do not have to spend extra money, it is necessary to carry out proper maintenance of the battery. Here are some helpful tips to help you extend the life of your lead-acid battery without causing damage:

  1. It is necessary to constantly remove dirt, oil and other debris from the battery case.
  2. Check, if necessary, tighten the battery fasteners under the hood.
  3. From time to time, the plugs for venting gases need to be cleaned, but the procedure is carried out carefully. At home, you can use a needle or toothpick.
  4. Check the wires that come out of the battery. They should not be damaged, oxidized. The fixing of the wires is made reliable.
  5. The electrolyte level is monitored inside using a glass tube. If necessary, add distilled water.

The subsequent check consists in the same rules, but also control of the density of the liquid in the battery, its correction is added.

A prerequisite for the durability of lead-acid batteries is to check the level and density of the electrolyte

Now you need to figure out what kind of battery malfunctions are and how to fix them.

Major malfunctions and methods of their elimination

Before studying the types of faults in the refrigeration system, it is necessary to study more widely the features of the main instruments used to detect failures. List of equipment used to detect a malfunction in the refrigeration system includes:

  • Pressure gauge;
  • Thermometer;
  • Leak detector;
  • Vacuum gauge;
  • Ampere-voltmeter;
  • Megohmmeter.

Malfunction symptom

Possible reasons

Recommendations for elimination

1. When the circuit breaker is turned on, the green lamp does not light

2. Compressor does not start, no noise.

3. Compressor does not start, noise is present, thermal relay is activated.

1.1. There is no mains voltage or the mains cable connection is loose. 1.2. Lamp burned out.1.1. Check the presence of voltage in the network, as well as the reliability of the connections. 1.2. Replace lamp.
2.1. There is no power supply in the network, the fuse is blown, the switch is off. 2.2. Faulty electrical wiring. 2.3. Sticking or breakage of the thermostat in the off position. 2.4. The thermostat is disconnected due to low temperature. 2.5. Resistance of motor windings several megohms2.1. Check the network, replace the fuse, turn on the breaker. 2.2. Check wiring. 2.3. Correct or replace the thermostat. 2.4. Replace the thermostat sensor. 2.5. The internal thermal relay has tripped. Wait 2-3 hours for the relay to return.
3.1. Faulty electrical wiring. 3.2. Very low voltage. 3.3. Loose contacts. 3.4. Motor winding damaged. 3.5. Phase voltage imbalance. 3.6. Mechanical compressor defect (jamming). Electric motor burned out.3.1. Check wiring. 3.2. Establish the cause and fix it. 3.3. Tighten contacts. 3.4. Replace compressor. 3.5. Establish the cause and eliminate. 3.6. Replace compressor.
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4. The system is functioning normally, but with a very short cycle time. 4.1. The thermal relay of the evaporator fan is very often activated. 4.2. The high pressure switch is triggered very often: insufficient air flow; dirty condenser; excess refrigerant; the presence of air in the system; the fan is not working. 4.3. Very often the low pressure switch is triggered: incomplete closing of the solenoid valve of the liquid line; a leak in the compressor valve; lack of refrigerant; the expansion valve filter is clogged; breakdown of the expansion valve. 4.1. Check the correct connection and the condition of the fan. 4.2 Check the high pressure switch. Check and eliminate the cause of the reduced air flow; clean the condenser; bleed refrigerant; remove air from the system; check and fix the fan. 4.3. Check the setting of the low pressure switch. Replace the solenoid valve; replace the valve plate or compressor; eliminate the cause and refuel; clean the filter; replace the expansion valve. 5. The system operates continuously or with a long cycle. 5.1. Lack of refrigerant. 5.2. The thermostat contacts are stuck or frozen in the closed position. 5.3. Very high heat load of the room to be cooled or poor thermal insulation. 5.4. Insufficient system capacity. 5.5. The evaporator is frozen. 5.6. Blockage in the system. 5.7. The expansion valve is clogged. 5.1. Check tightness, repair leaks and top up. 5.2. Clean contacts or replace thermostat. 5.3. Establish the cause and fix it. 5.4. Replace with a more powerful one. 5.5. Defrost. 5.6. Locate and eliminate. 5.7. Clean or replace.

B. The liquid line is frozen or fogged up. 6.1. The filter drier is clogged. 6.2. Liquid valve not open enough. 6.1. Replace. 6.2. Open completely.

7. The suction pipeline is frozen over. 7.1. The expansion valve is leaking too much refrigerant or is poorly matched. 7.2. The expansion valve is locked in the open position. 7.3. Evaporator fan is not working well. 7.4. Excessive refrigerant. 7.1. Adjust the expansion valve or replace. 7.2. Clean the expansion valve or replace. 7.3. Determine the cause and eliminate. 7.4. Drain off excess refrigerant.

8. Noise in the system. 8.1. Poor fixation of equipment or defective shock absorbers. 8.2. Nozzles knock. 8.3. The impeller is deformed. 8.4. The fan motor shaft is worn out. 8.1. Secure equipment or replace shock absorbers. 8.2. Bend over until contact is eliminated. 8.3. Replace the impeller. 8.4. Replace motor.

9. The temperature in the refrigerated space is higher than the required one. 9.1. Thermostat is not adjusted. 9.2. Low-performance expansion valve. 9.3. Insufficient evaporator surface. 9.4. Insufficient air circulation. 9.1. Adjust. 9.2. Pick up and replace. 9.3. Replace the evaporator. 9.4. Improve circulation.

10. The compressor has turned off, the lamps in the cabinets are off (the anti-theft switch is off).

10.1. The input circuit breaker in the air cooler control cabinet has tripped:

10.1.1. Power surge in the network.

10.1.2. Phase voltage imbalance.

10.1.3. Short circuit.

10.2 Low pressure switch tripped.

10.3. Air cooler fans failure.

10.1.1. Make sure that the mains voltage is normalized.

10.1.2. Eliminate and activate the compressor motor protection circuit breaker.

10.1.3. Check insulation resistance.

10.2.1. Check system charge. Refuel.

10.2.2. Check the low pressure switch (switch).

10.2.3. Wait for the compressor to start, see 11.1.

11. The red light is on only in the air cooler control cabinet.

11.1. Air cooler fans trouble (circuit breaker or internal fan thermostat tripped).

11.1.1. The fan blades of the air cooler are iced up.

11.1.2. One or more air cooler fan motors are defective.

11.1.1. Perform forced defrost until the ice or snow coat is completely removed from the fan blades, then turn on the fan circuit breaker.

11.1.2. Replace defective air cooler fans

12. Red lamps are on both on the panel of the EA- control cabinet and in the EB- control cabinet.

Compressor alarm (compressor motor circuit breaker tripped).

12.1. Increased compressor current draw. Overheating of the engine.

12.2. Power surge in the network. Phase voltage imbalance. Short circuit.

12.3. Lack of oil.

12.4. Liquid refrigerant in oil.

12.5. Low oil temperature.

12.1.1. Check FST parameter on EWDR 974.

12.1.2. Check the setting of the high pressure switch (switch).

12.1.3. Check oil level and cleanliness.

12.1.4. Check suction superheat.

12.1.5. Check the resistance of the motor windings and insulation.

12.2. Check mains voltage and wiring,

12.3 L. Check oil level.

12.3.2. Check the crankcase heater.

12.4. Prevent liquid refrigerant from entering the oil.

12.5. Wait until the oil warms up.

12.6. High condensing pressure.

12.7. Control circuit failure.

12.6.1. Clean the condenser.

12.6.2. Check condenser fan operation.

12.6.3. Check system charge.

12.6.4. Check the high pressure switch (switch).

12.6.5. Check the ambient temperature.