Tachometer sensor in a washing machine: tachogenerator, Hall sensor
A tachogenerator, also known as a tachosensor, is necessary to record the number of revolutions. It also measures the generated voltage. These are very important indicators that need to be accurately recorded. Monitoring these parameters ensures the machine remains operational and runs all modes and programs correctly. It also helps protect the washing machine from many malfunctions.
When the tachometer fails, the drum rotates uncontrollably. This means the machine's RPM may differ from the required value. This can be noticed when the machine malfunctions during the spin cycle.
The drum can rotate at the speed required for a given cycle. When the washing machine is running, the rotor spins, generating alternating electrical voltage. This voltage is sent to the control module. It analyzes the information received and decides whether to speed up or slow down the drum. If the speed is correct, it can remain constant. This way, the machine is monitored throughout all the preset programs.
Some modern brands of washing machines, distinguished by their high quality and reliability, use Hall sensors instead of tachometers. These are installed in the electric motor.
Typically, the following manufacturers use such devices:
- Siemens,
Bosch- and others.
This component is quite modest in size. When installed, it is secured to a stationary part of the electric motor. Its job is to monitor the magnetic field that arises during rotation. This sensor has three special outputs. They provide the data necessary to monitor the washing machine's RPM to the electronic control module. Based on this data, the module decides whether to increase or decrease the drum speed.
Tachogenerator failure
If you decide that the tachometer sensor is broken, then you should not rush into further action.
First, let's look at other possible causes of the problem:
- First, check the spin button. It's possible it's stuck, which could be causing the problem.
- Check that the tachogenerator is securely fastened. The washing machine vibrates during operation. These vibrations could have loosened it over time.
- Check the contacts with a tester (multimeter). When inactive, a normal resistance is close to 70 ohms. If the resistance changes when the motor shaft rotates, then our sensor should be working properly.
- Another possible cause is a lack of grounding. If a certain amount of charge from the drive belt gets onto the engine pulley, the engine's operation may become very unstable.
Check for these faults. If they are the cause, the washing machine will work normally once you fix them. If the problem persists after fixing these issues, then either the electronic control module or the tachogenerator is faulty.
In neither case do we recommend replacing the part yourself. We recommend leaving this work to professionals. However, if you're confident and have the necessary skills, you can replace the tachometer sensor or module yourself.
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Hello everyone! I have a problem like this: when I turn on the machine for the first time, while it's still cold, it runs the entire cycle of any program at 5, then things get interesting. I set the program, it washes, but before the rinse cycle, meaning it turns on, rinses, drains the water, and... the drum spins endlessly at one speed, but it's clearly lower than normal and nothing else happens. I checked the motor and it seems hot, but my hand tolerates it. I checked the tachogenerator, and the parameters match yours: 70 ohms, etc. Can you suggest anything? Thanks in advance.
It all depends on the brand of your SM. On older Samsungs, the high-speed engine relay failed. Good luck.
My tachometer is reading 530 ohms. Is this normal? (I know there are 165 ohms.) My Zanussi FA 1023 washing machine is either trying and failing, or it won't even start, or it's spinning all the time. It's all a bit unclear. What's wrong with it?
The Whirlpool AWG328/1 tachometer has a resistance of 520 ohms, and the resistance changes slightly as the magnet inside rotates. Is this normal for the sensor? Sensors available with the appropriate dimensions (internal diameter 24 mm, external diameter 39 mm, and height 12 mm) have a stated resistance of 70 ohms.
Thanks for the tips. I turned it over, checked the contacts, put the washing machine back in place, and it worked. It was error 3E.
Good evening, I'm having a problem with my Indesit washing machine: right at the start, the machine fills the tank with water (soaks the clothes) and then drains. It refills the tank, rotates the tank 2-3 times, and then starts draining! This shouldn't happen! And the draining continues until I unplug it. Can you tell me what the problem is? Thank you very much in advance!
After my Indesit wil85 washing machine stopped working, the door (lock) indicator and the easy iron indicator were flashing. I would be very grateful for a solution to this problem!
Good day! My tacho shows 37 ohms. Is this normal?
Good evening! I'm having a problem with my Hansa washing machine. It displays the E08 error code almost every time I wash. The washing machine stops and doesn't spin, even though the filter is clean and the doors are checked. Can anyone tell me what this could be and how to fix it?
Good evening! I have a Candy compact front-loading machine! I recently developed a spin problem—it doesn't display an error, but finishes the program normally (it displays "End"). The laundry remains wet! When I select just spin, it sometimes works, sometimes not! When I run it without laundry, it runs normally and picks up the speed. When loading laundry, depending on the amount and weight, the laundry may remain wet! I previously replaced the heating element!
Try it without any laundry. I also changed the heating element on the Virula. The problem was the uneven distribution of the laundry. The wool sweater was soaked in water and was causing overload.
My LG washer has been washing for 2-6 cycles and the tachometer is failing. Can you tell me why?
Hello! My HANSA washing machine (manufactured in 2004) starts washing, but after the drum has made a couple of spins, it displays an E21 error. We checked the tachometer resistance. It's 228 ohms, and its dimensions are d20/D31/H13mm. Is it working properly?
My Samsung Bio Compact drum isn't spinning, and I can't find the tachometer. The error message says it's the tachometer. Please help.
Could you please help? My Miele w3240 washing machine spins at maximum speed when turned on, and the tachogenerator resistance is 265 ohms. Is this normal, and what should it be for this model? I've searched a ton of resources, but I can't find the answer. Please help!
Hello. Could you please tell me what's wrong? I have an Indesit wi82 washing machine. The entire cycle runs smoothly, without any issues. But as soon as the spin cycle starts, it doesn't turn off automatically; it keeps spinning. I have to turn it off manually. What's wrong? Thanks in advance!
I've replaced four hall sensors on my LG in two months. What's causing the sensor failure?
I have a Samsung S821. The engine burned out initially, so I found a used one and installed it. It started cranking at a crazy speed, so I checked the tachometer. Both the old engine and the new one were 40 ohms. I don't understand which relay controls the tachometer.