The refrigerator Atlant stopped cooling, but the motor hums only for a few seconds or is silent? Often the problem lies in the electrical part of the motor-compressor, and the only way to confirm this without disassembling the entire system is testing the windings. This procedure allows you to quickly determine whether the unit is alive or needs to be changed without calling a technician for initial diagnostics.
To carry out the work, you will need a minimum set of tools that any home craftsman will have. The most important thing is to follow safety precautions, since we will be working with high voltage. In this article, we will analyze a step-by-step algorithm of actions, typical faults and methods for identifying them.
Before grabbing screwdrivers, make sure that you understand the essence of the process. Dialing is a measurement of the resistance of electrical circuits. If the circuit is intact, the device will show a specific value; if not, it will go to infinity or zero. This is a basic method of troubleshooting in electrical engineering.
Preparation for diagnostics and safety measures
The first step should always be a complete deenergization device. Unplug the power cord from the outlet. Even if the refrigerator is not working, life-threatening voltage could remain in the circuit. Let the equipment stand for 10-15 minutes so that the capacitors, if any, are discharged in the starting relay.
You will need access to the bottom of the housing where the compressor is located. Models Atlant usually have an open design, but sometimes it is necessary to remove the back metal cover. For work, prepare a multimeter (tester), a screwdriver and pliers. If you do not have a multimeter, you can use a simple “control” (a light bulb with wires), but the accuracy will be lower.
⚠️ Attention: It is strictly forbidden to touch the metal parts of the compressor or wires while turning on the refrigerator to the network for a “hearing” test. This can lead to a severe electric shock, since the housing may become energized if the insulation breaks down.
Visually inspect the starting relay and wires. If you see melted plastic, blackened contacts, or smell a burning smell, diagnostics may no longer be needed - the unit is clearly faulty. However, in order to understand whether the compressor or just the “tablet” (starting relay) has burned out, you need to ring the windings.
Make sure that the workplace is well lit. You will have to work in a confined space behind the refrigerator where there may be cobwebs and dust. Wipe the contacts with a dry rag to eliminate the influence of moisture on the device readings.
Removing the start relay and accessing the contacts
To get to the winding terminals, you need to remove the start-protective relay. On refrigerators Atlant it is attached to the side or top of the compressor and covered with a plastic casing. Carefully remove the casing by snapping the latches or unscrewing the screws.
The relay is held on three contacts, which are inserted into the connector on the compressor housing. Take a photo of the position of the wires before removing them so that you don’t mix up the phasing during reassembly. Gently rock the relay from side to side to remove it from its terminals. Do not use excessive force to avoid breaking the ceramic insulators.
After removing the relay, you will see three contacts arranged in a triangle. They can be signed with letters R, S, C or have color coding. Some models Atlant use the marking 1, 2, 3. It is important to understand which contact is responsible for what in order to take measurements correctly.
Contacts can be oxidized. If they show green deposits or rust, carefully sand them with fine sandpaper or a knife until they are shiny. Oxides create additional resistance, which can distort the measurement results and lead to a false conclusion about a motor malfunction.
Determination of compressor winding terminals
Three pins on compressor - these are inputs for three different circuits. Two of them lead to the working windings, and the third is common. Understanding their purpose is critical for correct diagnosis. Usually the circuit looks like this: a common wire, a starting winding and a working winding.
In the classical circuit for single-phase motors used in Atlantakh, the winding resistances are different. The working winding is made of thicker wire and has less resistance. The starting winding is wound with a thinner wire, so its resistance is always higher.
To determine which terminal is located, use a multimeter in resistance measurement mode (Ohm). Call pairs of contacts with each other. You will get three resistance values. The greatest value will be between the starting and working windings. The smallest is between the working winding and the common wire.
- 🔌 Common contact (C) —the point where the resistance to the other two contacts is minimal (the sum of the resistances of the two windings).
- ⚙️ Working winding (R) —has an average resistance, usually in the range of 10-25 Ohms.
- 🚀 Starting winding (S) —has the highest resistance, often 1.5-2 times higher than the working one.
The table below shows approximate resistance values for popular compressor models Atlant. Remember that the exact numbers depend on the motor power and year of manufacture.
| Pair of contacts | Circuit type | Normal resistance (Ohm) | Fault symptom |
|---|---|---|---|
| Working - General | Working winding | 10 - 25 Ohm | Infinity (break) or 0 (short circuit) |
| Starting - General | Starting winding | 20 - 40 Ohm | Infinity (break) or 0 (short circuit) |
| Working - Starting | Sum of windings | 30 - 65 Ohm | Discrepancy with the sum of the other two |
| Any - Housing | Insulation | Infinity (∞) | Any value (breakdown to the case) |
The process of dialing with a multimeter
Turn on the multimeter and put it in resistance measurement mode to the limit of 200 Ohms or 2 kOhms. If the device is analog (with a pointer), be sure to perform a zero calibration by connecting the probes to each other. Digital multimeters do not need calibration, but it is necessary to check their operation by shorting the probes (should show 0 or close to zero).
Attach one probe to one of the compressor contacts, and the second to the other. Record the reading. Then move the probe to the third contact and record again. You need to get three values for all possible pairs. Compare them with the data from the table above. If the device shows “1” or “OL” (Over Limit), it means there is a break in the circuit Pay special attention to checking for a “breakdown”. Press one probe onto any copper fitting on the compressor (where the tube goes in) or onto an unpainted part of the housing. Using the second probe, touch all three contacts in turn. The device should be silent and show infinity. If the arrow trembles or numbers appear on the screen, the insulation has burned out and current flows to the housing..
Pay special attention to checking for “breakdown”. Press one probe onto any copper fitting on the compressor (where the tube goes in) or onto an unpainted part of the housing. Using the second probe, touch all three contacts in turn. The device should be silent and show infinity. If the arrow moves or numbers appear on the screen, the insulation has burned out and current flows to the housing.
⚠️ Attention: If the multimeter shows a resistance close to zero (less than 1 Ohm) between any two contacts, this means interturn short circuit. You cannot operate such a compressor - it will burn out instantly or knock out the machine in the panel.
☑️ Diagnostic checklist
Interpretation of results and Troubleshooting
You need to be able to read the resulting numbers correctly. If the resistance of one of the windings differs significantly from the norm (for example, 5 Ohms instead of 15), this is a sign. Such an engine will work, but will quickly overheat and the thermal protection relay will trip, after which the refrigerator will turn off again. interturn short circuit. Such a motor will work, but will quickly overheat and the thermal protection relay will trip, after which the refrigerator will turn off again.
If the winding breaks, the device will show infinite resistance. Often the thin wire of the starting winding breaks. In this case, the compressor will hum, but will not start, since no starting torque is created. The hum will continue until it heats up and the thermal protection opens.
A breakdown to the housing is the most dangerous malfunction. It means that the insulation inside the motor is broken, and a potential of 220 volts appears on the metal casing. If you touch it with your hand, you may receive an electric shock. Such compressors Atlant must be replaced immediately.
Why can the resistance “float”?
When the windings heat up, the copper resistance increases. If you have just tried to start the refrigerator, let it cool for 30-40 minutes before calling, otherwise the readings will be incorrect.
Sometimes there is a situation when all three contacts ring with each other with the same or similar resistance. This may indicate that the common wire is broken inside, or that the motor has a specific winding pattern (which is rare for household refrigerators). In 99% of cases, for Atlantov the resistances should be different.
Typical errors in diagnostics
Beginners often forget that the starting relay also has an internal circuit. If you call the compressor together with the relay, the results will be incorrect. Always remove the relay completely. Another mistake is the “floating” test, when the compressor is not fixed and vibrates when touched by the probes.
Another common mistake is using the “test” mode (tweeter) instead of the resistance measurement mode. The tweeter will work at both 10 Ohms and 100 Ohms, without making it clear whether the value is normal. For accurate diagnostics, you need a digital indicator in Ohms.
Do not ignore the condition of the wires going to the relay. It often happens that the compressor itself is working, but the wire is broken or oxidized at the point where it enters the block. Carefully inspect the insulation along the entire length of the visible wires.
Frequently asked questions (FAQ)
Is it possible to check a compressor without a multimeter?
It is impossible to accurately determine the state of the windings without a device. You can only judge indirectly by the operation: if the motor hums and immediately clicks, the starter is likely to break or jam. If the plugs are knocked out, there is a short circuit. But to be sure, you need a tester.
What should the compressor temperature be when checking?
The compressor should be cold. After work, the oil and windings are hot, which changes the resistance of the copper. Allow the equipment to cool to room temperature before diagnostics.
What to do if the resistance is normal, but the refrigerator does not turn on?
Most likely, the start relay, thermostat or control module is faulty. A hydraulic wedge (jamming of the piston group), which is not detected by an electrical test, is also possible.
Is it possible to start a compressor with a break in the starting winding?
Theoretically, by starting the shaft manually or using a capacitor, but this is a temporary measure. The engine will operate with overheating and low efficiency, which will quickly lead to its final failure.
Where can I find the wiring diagram for my Atlant model?
The diagram is usually drawn on a sticker attached to the start relay or on the back wall of the refrigerator. Information can also be found in the service documentation for the compressor model code.