Apr. 08, 2020
Many users will encounter problems in the temperature control system when using dry-type transformers. In fact, for this product, the detection of operating temperature and its alarm control is very very important. Today, transformer manufacturer came to tell you about this matter.
First of all, we must understand that the winding temperature exceeds the insulation withstand temperature and the insulation is destroyed, which is one of the main reasons that the dry-type transformer cannot work normally. Therefore, the safe operation and service life of the dry-type transformer depends largely on the dry-type The transformer winding insulation is safe and reliable.
1. Temperature display system: The temperature change value is measured by a Pt100 thermistor pre-buried in the low-voltage winding, and the temperature of each phase winding is directly displayed (three-phase inspection and larger value display, and historical higher temperature can be recorded), It can output higher temperature as 4 ～ 20mA analog quantity. If it needs to be transmitted to the computer of remote plate rolling machine (distance up to 1200m), it can be equipped with computer interface, one transmitter, and more can monitor 31 transformers at the same time. The over-temperature alarm and trip of the system can also be operated by the Pt100 thermistor resistance signal to operate the plate rolling machine, further improving the reliability of the temperature control protection system.
2. Over-temperature alarm and trip: collect the temperature signal of the winding or core through the PTC non-linear thermistor temperature measuring resistor pre-buried in the low-voltage winding. When the temperature of the dry-type transformer winding continues to rise, if it reaches 155 ℃, the system outputs an over-temperature alarm signal; if the temperature continues to rise to 170 ℃, the transformer can no longer continue to operate, and the over-temperature trip signal must be sent to the secondary protection circuit. Make the transformer trip quickly.
3. Automatic fan control: temperature signal is measured by Pt100 thermistor temperature resistance pre-buried in the hot part of low-voltage winding. The dry type transformer load increases the plate rolling machine, and the operating temperature rises. When the winding temperature reaches 110 ℃, the system automatically starts the fan cooling; when the winding temperature is as low as 90 ℃, the system automatically stops the fan.
Add: Room A1109, No.483 Yulan Street, Baoding City, Hebei Province, China