RLV vapormatic starters are used when the driven machines are of great inertia or when the rating power of starting / driven machine is low. They have the following advantages:
ReliabilityNo moving parts other than the short circuit contactorUnaffected by damp, dusty or corrosive atmospheresSavingsCable saving: integral contactorsFacilitate installation beside motorsElectrical and mechanical maintenance considerably reducedCompetitive priceAdaptabilityEasy adjustment gives "made to measure" starting conditions and conversion to suit different drives.Operating principle
The starting principle is based on the difference in resistivity between a liquid electrolyte and its vapour, contained in an electrode chamber.
The passage of the initial rotor current causes immediate partial vaporisation of the electrolyte and instantaneously adjusts resistance and starting torque to optimum values. During the run-up to speed, the thermal interchanges which occur progressively decrease the resistance.
A timed contactor then short circuits the low residual resistance.
The starting torque is determined according to the requirements of the driven machine or the current limitation.
