How to fix a floor electronic scale?

Very often, the idea comes to us that it is time to take care of your health and adjust your weight. Especially often this thought worries us on New Year's Eve, after a plentiful feast. And so, you take out the scales, and they are faulty or incorrectly show the weight, and without them you can’t control the weight in any way. Do not despair, today we will tell you why there can be such a breakdown and how to fix a floor electronic scale with your own hands.

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Features of electronic scales

Electronic scales are a much more complex device, unlike a similar mechanical device. Indications in the electronic device are displayed, and the principle of operation is based on the functioning of the voltage sensor. The device is turned on automatically (when a person becomes on them) or using a special button.

Important! The weighing error ranges from 100 to 1000 g, and the maximum load is from 100 to 220 kg, depending on the model. manufacturer and cost.

Floor electronic scales consist of the following elements:

• Display.
• Load cells.
• Electronic circuit board.
• Buttons.

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What to do if floor-mounted electronic scales do not work?

If the electronic floor scales do not work and do not turn on, then the cause may be dead batteries. To make sure that it is the power source, remove the battery and check it on any working electronic device. If the device with this power supply also does not function, replace the batteries and the balance does not need further repairs.

Important! Sometimes, a tablet (battery) pulled out of the balance can work on another electronic device, but this does not mean that it is suitable for the balance. Find a brand new battery or other power source that can supply 3 V DC to the terminals. If the scales work, then further repairs are not advisable.

As for the buttons, in simple models they are completely absent. But, in more expensive models, the buttons are usually touch-sensitive, so most likely the problem is not with the buttons.

Important! The most important thing that you need to remember the owner of the electronic scale, you can not touch the display! The display is beyond the scope of our capabilities. Do not touch any fasteners on the display, screws, glue that fastens the display - if air enters under the sealed glass, the polarization of the crystals will be violated, and the screen will turn black in unsightly stains.

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What are load cells, can they break?

Electronic scales are endowed with a fixed platform, and the legs are engaged in the measurement. Under each leg is a sturdy frame made of a special alloy that can be deformed under the weight of a person. These changes are so small that they are not even visible to the human eye, and even such an accurate device as the construction level cannot always determine them. Each frame has a tiny plate, which in diameter reaches no more than 2 cm. This is the main sensor unit of the electronic device.

The most sensitive plate is firmly imprinted in the frame. This plate is poured with glue or compound.Three wires are connected to it, providing a measurement of the resistance of the shoulders of the bridge. At that moment, when a person gets on the scales, all four frames bend and divide the excess weight among themselves. Indications that are displayed on the screen are obtained by summing all the data. For the mathematical calculations, the circuit board of the balance is responsible. Three wires are suitable for it from each corner of the frame.

The bridge itself is a kind of square, on each side of which there is a resistor. Power is supplied to one diagonal of the bridge, and readings are taken from the other.

As you can see, weight sensors are ordinary pieces of iron that are very difficult to damage, because they are not afraid of even moisture (unlike a printed circuit board). Sensors can only be destroyed mechanically, so the reason that the electronic floor scales do not work can still be in them.

Next, we’ll show you how to fix a floor electronic scale if it’s not about batteries at all.

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How to fix electronic scales?

If it’s not about the batteries and you are determined to fix the electronic floor scales yourself, follow these instructions.

Step 1. Disassemble the device

First of all, the device must be disassembled. To do this, remove 2 3-volt batteries to de-energize the device and unscrew the screws on the bottom cover

Step 2. Perform a visual inspection

Under the cover you will see 4 legs, a printed circuit board, a battery compartment, a screen with buttons and wires connecting all these elements. The front and rear legs have a slight difference - a rubber ring and additional contacts with wires. The first time you press the scales, the rubber ring should flatten, and the contacts close and as a result, the scales turn on. After switching on, the device waits for the closure of both buttons, this will mean that the person stood on the scales with two legs.

Having carefully examined everything, examine:

• The quality of electrical connections.
• Installation of the electronic board.
• The integrity of all the details.

Step 3. Identify and repair a mechanical problem.

After a visual inspection, determine the nature of the problem and proceed with the repair:

1. Solder any torn wires into place.
2. If the cable connecting the board and the display does not fit snugly, then slightly raise the board and, as tightly as possible, push it to the display.
3. Then take a small wooden block and place it on the bottom of the case. Thus, the bar will act as a retainer.
4. If the balance stops working due to dust and debris entering it, clean the appliance. Do this carefully so as not to damage the pins and microcircuits.
5. If the internal frames are bent, then level them using standard measuring tools: building level, corner, vernier caliper. This malfunction can occur if an overweight person stands on the scales and bends his legs.
6. If the tracks of the electronic board are damaged, then clean the place of the defect with a fine emery cloth, degrease and puddle. Solder a jumper or a large layer of tin on top of the damage. At the end - cover the damaged area with varnish (nail polish is also suitable).
7. If the balance has been used for a long time, then the contact ends of the device have thinned. Locate the relay in which they worn and replace the contacts. Make and solder the contacts for reliability.

Important! Usually, all mechanical damage leads to the fact that the device readings are incorrect. After you correct all the damage, the balance will fully recover. However, if a visual inspection does not reveal any damage, then proceed to the next step - repair the strain gauge.

Step 4. Troubleshoot using a tester

If visually the balance is in order, then use the tester to find the fault:

1. Each sensor is carefully soldered from the board.
2. Measure the resistance between the three wires.
3. In all 4 corners, the indicators should be the same, if there is a gap somewhere, then a breakdown is detected.

Troubleshooting Instructions:

1. Carefully pick out the glue (compound) covering the plate. Remember that any mechanical damage to the part can lead to a complete failure of the assembly.
2. Inside will be a copper plate with three wires. If one of the wiring is torn, then restore the electrical connection.

What to do if the problem is in the sensor?

If the sensor is completely defective, then you can find another with identical parameters, so that the balance does not “lie” much.

Important! As soon as you find a new sensor, there will be a calibration problem, because each sensor is unique, even if two of them came off the same conveyor. Therefore, bridge connections are guaranteed to be inaccurate.

In order not to use special equipment for calibration, there are small tricks that will help correct the situation with a broken sensor:

• Simply release it from the load.
• Using conventional resistors, simulate the desired values ​​of zero load.

In the first case, the trick will work if the sensor was incorrectly calibrated earlier or lied. And in the second case, the process is simple, because you have already measured the resistance. Disconnect the faulty sensor, and let it play the role of the foot (the adders will count the weight of this foot as zero), and connect the remaining sensors according to the diagram and lay it inside the case.

Important! Repair of the balance may be necessary if it was calibrated incorrectly. To restore it: press the power button and hold until you see the word CAL on the screen. Then a digital mass value will appear. It is with his help that calibrate. To do this, use any item whose weight you know for sure. Put the item on the scale. After a few minutes, the word PASS appears on the display. Remove this inscription and turn off the balance, and then turn on the appliance again.

Step 5. Assemble the device

Put all the parts in place, insert the batteries into the compartment, tighten the bolts. Perform a control weighing.

As you can see, repairing electronic floor scales is not so difficult, because this is just a bunch of resistors and a small electronic board. But if the scales are under warranty, then entrust this matter to professionals.

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Repair of mechanical scales with video

Of course, now everything is in fashion electronic, but well-tuned mechanical scales can also accurately monitor our weight. A primitive spring of mechanics will be able to give a hundred points of odds to smart load cells.

The device of mechanical scales

Under the movable platform is a housing that includes:

• Rocker with arrow and dial.
• Sensitive spring that attaches to a horizontal plate.
• Horizontal plate.
• Four metal shoulders that are connected in pairs.
• Four motionless legs.

The measuring spring is a heart weight, because its tension is proportional to the measured mass.

Important! The scale of mechanical weights is broken down by kilograms (less often by 500 g).

Most often, floor scales do not work due to exceeding the maximum permissible weight. The arrangement of the mechanical balance is such that only load-bearing parts made of metal can be damaged.

Important! The spring and the hands with the dial practically do not fail. The shoulders or the base may bend.

In the event of a component failure, repair of the mechanical balance is as follows:

1. Carefully disassemble the balance.
2. Remove the deformed part.
3. Repair the breakdown by returning the part to its original shape.

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Stock footage

We hope that thanks to our recommendations, you were able to restore the balance and now they are responsible for your ideal weight and good health.