For terminals, electrical engineers need to understand is the process of terminals in use under the current. At present, UL, IEC, CSA, DIN and other institutions in determining Terminal power and performance specifications of the product and there is no uniform standard. Users need to understand the difference between UL and IEC specification. Manufactured in Europe terminals product specifications using IEC standards, and in the United States manufacturing products with UL standards.

This is very different between the two standards. Does not understand the method for determination of product specification engineer will take on considerable risk, terminal blocks selection device is likely to fall short of the required level of power, or use needs far exceeded the design specifications of the device. In Europe, the device's current rating is determined by monitoring current increases temperature of the metal conductor. When the metal pin temperature of 45 ° c higher than the ambient temperature, surveying staff on the current value of the rated current of the device (or maximum value). Other allowable current value of IEC specifications, it is the largest 80% of Terminal current. And unlike the UL standards will enable the metal temperature 30 ° c higher than the ambient temperature of the conductor current nominal value for the current value of 90% for the device.

We can see that the metal parts of the temperature of the conductor is a very important factor in all applications. More important for industrial equipment. Industrial equipment typically requires working in temperatures up to 80 ° c environment. If the Terminal temperature is higher than the temperature of 30 ° c, 45 ° c, the terminals will exceed 100 ° c of temperature. Depending on the selected device type and nominal value of insulation materials, terminals must be less than the rated value of current work, so as to ensure that they can work reliably in the desired temperature range. In some cases, suitable for compact packaging materials may not be able to meet the thermal requirements very well, so when used in this type of terminal devices must be significantly less than the rated value of current.