Metal detectors may have various problems under long-term use, so we need to understand common problems and learn how to solve them. Next is the knowledge of metal detector troubleshooting, and I hope it will be helpful to those who need it.
There is a long beep after turning it on or after a while
The detector does not need to be adjusted, and the switch is also special: forward is high sensitivity, backward (cannot be locked) is low sensitivity, and the middle is off.
When there is a long beep, just press the button "RESET" in the middle of the front of the detector to get rid of it.
The instrument is an unstable, false alarm
First, stop the conveyor belt from running. If the instrument does not alarm, the instability is caused by the frame. If the instrument still alarms after the conveyor belt stops, the instability is caused by the instrument.
Instability caused by the instrument, please check the following:
- Whether the grounding of the power supply is good.
- Whether the floor where the instrument is placed is vibrated.
- Whether there is moving metal near the instrument, such as trolleys, inspection tools, operator's watches, keys, etc.
- Whether there is a large load on the phase line of a 220v power supply shared with the instrument, such as electric welding machines and large motors.
- Whether the metal detector power supply voltage is stable, and whether there is interference such as a high-power frequency converter around the instrument.
- Whether the sensitivity is set too high, if the sensitivity is too high, the sensitivity can be reduced appropriately.
Instability caused by rack, please check the following:
- Whether the rack support is loose.
- Whether the rack screws are loose.
- Whether the conveyor belt rubs against the inner wall or bottom of the probe, and whether the conveyor belt is polluted. When the conveyor belt is mixed with metal, it will cause the instrument to periodically alarm. If the instrument does not alarm when the conveyor belt stops and always stops at a fixed position after starting the conveyor belt, it can be judged that there is metal mixed on the conveyor belt at the probe position. At this time, you can use a clean towel dipped in alcohol to wipe the front and back of the conveyor belt until the instrument does not falsely alarm.
- In the northern region, the weather is dry in winter, and the sound of static sparking may be heard when the conveyor belt is running, which will cause the instrument to be unstable. At this time, you can wipe the conveyor belt with a wet towel to eliminate static electricity.
The conveyor fails to start
Open the instrument box, (pay attention to protect the circuit board, do not cause a short circuit) lightly press the start/stop button, and you can see that the relay RL1 on the lower circuit board will act.
If the relay does not work, you can first use a multimeter to measure the reverse voltage of the diode next to the relay. The voltage here changes between 0-15V when the start/stop button is pressed. When the voltage here is 15V, the relay should pick up.
If the voltage is normal but the relay does not work, it can be replaced with the same type of relay. If the voltage here is abnormal, first check whether the wiring behind the panel and the wiring in the instrument box is firm or loose.
Detector vibrating, beeping irregularly, sensitivity becomes very low
If it is used indoors, close to electric wires, and two detectors are used in adjacent areas at the same time, there will be electromagnetic interference in the environment.
Keep a distance of at least 6 meters between the two detectors, and lower the sensitivity until the unstable signal disappears.
The speaker volume is low
Low battery, the wrong battery was used.
To replace the batteries, use only alkaline batteries.
The target ID display is not fixed, and various prompt sounds appear
Multiple targets have been detected, the soil mineralization degree is high, and the detector sensitivity is high.
Move the search coil at different angles, use the ground-clearing function, and turn down the sensitivity.
Conveyor belt deviation
- Judging whether the tension of the conveyor belt is appropriate if the conveyor belt is too loose, it is easy to run off.
- On the pallet support of the conveyor belt, there are two adjusting bolts near the outlet of the conveyor belt, through which the tension of the conveyor belt can be adjusted.
- Observe whether the tightness on both sides is consistent. If the tightness on both sides is inconsistent, it will also cause the conveyor belt to deviate.
- By adjusting the tension on both sides to be the same through these two adjusting bolts, the problem of deviation of the conveyor belt can be solved.
The instrument has no sensitivity
- Check whether there are large metal foreign objects in the probe hole, such as coins, keys, screws, etc., and remove metal impurities.
- Whether the underwater metal detector product selection is correct.
- Whether to be selected in the NG disabled state. In this state, if the instrument detects any metal, it will not perform alarm and elimination actions, but the signal indicator will indicate.
Instrument periodic false alarm
- Whether the conveyor belt is contaminated by metal impurities. If the conveyor belt is contaminated by metal impurities, the detector will alarm every time the contaminated part passes the detection area. Clean the conveyor belt to remove metal impurities.
- Even if the conveyor belt does not rotate, the instrument still periodically false alarms. At this time, there may be a high-power interference source around the detector, such as a vibrating screen.
Instrument irregular alarm
- Occasionally, the detector has irregular false alarms, which may be caused by the unstable power supply, which can be solved by adding a regulated power supply.
- When the product is not detected, the instrument is normal, but when the product to be detected passes through the detection area, it still alarms even if the product does not contain metal impurities, which indicates that the detection parameters are not adjusted properly.
- If there are still false alarms after the conveyor belt stops, check whether there are high-power interference sources around the equipment, such as motors, engines, etc.
- Check for large pieces of moving metal around the device.
- Check whether the grounding wire of the power supply is in good condition. In order to ensure the stable operation of the instrument, a solid grounding wire is required.
The motor won't start
- On the control box panel, lightly press the "Start" and "Stop" buttons, and observe whether the relay in the control module operates. If there is action, it means that the motor is damaged or the starting capacitor is damaged. You can buy the same model motor and replace it. Or contact the company's after-sales service department. Non-professionals are not allowed to repair without authorization to avoid the risk of electric shock.
- If the relay does not operate, the control module may be damaged, or a connection wire may be loose.
When the product passes through the detection head, it will alarm if there is no metal impurity
Check whether it is a product that has been debugged. If the detection product is not set, you need to re-adjust the detection parameters.