Manufacturing for STV has been discontinued. As an alternative, please refer to P342, 889 or G30.

The Type STV relay is a single-phase static overexcitation relay. It consists of an overexcitation sensing unit which has a linear volts per hertz pickup characteristic, and a timing unit to provide a definite time before initiating some protective action. A target seal-in unit is also provided to protect the timing unit contacts during tripping duty. 

The Type STV relay is designed specifically for equipment protection in case of overexcitation. Overexcitation of a generator or power transformer may occur during start-up, shutdown, or as result of remote load rejection. As as result, overheating due to core saturation within a very short time may cause severe damage. This relay, employing a constant volts per hertz pickup, recognizes overexcitation and initiates some appropriate action to protect the equipment. 

Features and Benefits 

• Target seal-in units
• Drawout case

Applications 

• Transformer and generator protection
• Alarm and backup protection

Protection and Control 

• Overexcitation
• Adjustable pick-up voltage
• Adjustable time delay