What Should We do When there is An Electrical Failure in the Vacuum Furnace?

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Vacuum furnaces are widely used for heat treatment of metal materials under low vacuum, reducing and protective atmosphere, and can also be used for heat treatment of special materials, such as the development of carbonization processes for carbon products. The heat preservation material in the furnace adopts alumina ceramic fiber, which has a good effect of energy saving on body temperature. The outer closed vacuum tank is equipped with a double-layer water cooling system. The whole machine has a novel structure and is easy to operate.

Abnormal temperature, including over-temperature alarm, or display temperature not reaching the set value.Troubleshooting method for over-temperature alarm:

1. First check whether the parameters of the thermostat in the working area are normal, and check all the parameters with reference to other thermostats in normal use.

2. According to the circuit diagram, check whether the output terminal of the solid state relay in the corresponding working area is broken down. This method: after power failure, use a multimeter to measure the resistance between two points on the output terminal of the solid state relay. Normally, the resistance will be more than a few megohms. If it is broken down, there is almost no resistance, and it must be replaced with a new one according to the same model,

3. When the power is turned on, gently shake the thermocouple probe in the corresponding work area by hand to see if the corresponding thermostat shows a large fluctuation range. If this phenomenon occurs, it means that the thermocouple probe is in poor contact and needs to be replaced with a new one.

The display temperature is too low to reach the set value:

1. Similarly, first check whether the parameters of the thermostat in the working area are normal and whether there is an output signal.

2. Check whether the thermocouples in the corresponding working area are damaged. In order to verify whether these thermocouples are in good condition, you can exchange them with the thermocouples on the normal thermostat and connect them to the thermostat, and observe the temperature display. If the thermocouple is indeed damaged, it must be replaced. (Note: If the thermocouple to be replaced is in the inner cavity, the vacuum sealing performance will also be involved.

3. If there is no problem with the thermostat and thermocouple, you need to test whether the heating tube is energized and working normally. Method: After the power is turned on, start the heating. According to the circuit diagram, directly use a test pencil to test the wire connected to the heating tube in the corresponding work area (the white high temperature wire is on the solid output terminal) to see if there is electricity. If there is electricity, you need to use a clamp meter to measure whether the current is different from other working areas. Normally, the difference is not big.

4. If no electricity arrives, you must check the circuits one by one according to the circuit diagram to see at which link the electricity is cut off, and whether any components are burned out.

The vacuum cannot be drawn up or is too low:

1. First of all, confirm whether the vacuum source of the plant is normal and whether the compressed air pressure is normal.

2. Check whether the vacuum meter is in good condition, and compare it with the vacuum meter in normal use to see if the parameters are normal?

3. Check whether the door is closed tightly, whether the sealing film at the door is damaged or deformed, and whether there is any foreign matter on the door panel? please check carefully!

4. If there is no problem with the door, you need to check the corresponding work area pipeline, pneumatic valve, thermocouple entry and other locations. Usually there are more cases at the entrance of the thermocouple, because if there is a replacement of the thermocouple, the vacuum sealing performance will often be destroyed, and the AB glue must be re-sealed for sealing.