NewElec’s 330 Series motor protection relays are designed for heavy industry service and are suitable for use on wound rotor motors used on moving machinery such as hoists and overhead cranes. As thermal overloading or overheating of the motor may lead to insulation failure and damage of the winding, the motor should be protected against these adverse conditions. Motor protection against mechanical over loading, stalling of the motor shaft, low supply voltage, single phasing of supply mains, unbalancing of supply mains and sudden phase loss, as well as rebuilding the supply voltage is necessary. In addition, the 330 Series relays continuously calculate heating and cooling rates, ensuring that motor loading and CDF are maintained within the tolerable thermal envelope of the protected motor.
Contact Raymond Evans, NewElec, Tel 012 327-1729, email@example.com
Source: EE plublishers