Protection Relay (MELPRO-A series)
Product Features
Protection relay for digital type high voltage power system maintain high stability and stable characteristics.
Improve reliability by sufficient self-diagnosis function and dualoutput circuit.
Since compatible with the conventional model, renewal to MELPRO-A is easy.
High Reliability
Adopt the highest performance CPU situated in the front line of the digital age.
The high speed digital computation realizes the high accuracy operating characteristics never before possible. The operating characteristics are configured by the software, so that little deterioration and the stabilized operation can be realized.
Adopting self-diagnosis function for countermeasures against problem may arise.
The self-diagnosis function which monitors continuously the input, built-in power source and CPU is equipped. In the failures occurring of the relay, they can be detected immediately by the self-diagnosis function. Furthermore, dual output circuit makes possible to prevent the occurrence of misoperation due to the hardware failures.
Superior resistance to attack by tough environment
Adopt the structure to be resistant to the disturbances such as the electric surge and noise, harmonics, radio noise from the cellular phone, temperature and humidity.
High Performance
MOC-A1 type
The optimal operation time characteristic can be chosen along with the characteristic of the overcurrent relay at the sending distribution substation.
Four kinds of operation time characteristics are installed as a time-delayed element.
Since the optimal characteristic can be chosen along with the characteristic of the overcurrent relay at the sending distribution substation or the conditions of down stream apparatus, design time can be limitted as the minimum.
MDG-A1 type
By the substantial measurement display function, a setup of a setting value is easy.
Since the relay itself is always measuring and indicating Io and Vo of a system, the residual Vo and Io can be grasped, and the optimal setting is possible.
The data in case of the earth fault is saved by the“ System fault record function”.
The system input value at the time of the occurrence of the earth fault is measured and saved.
Since each value, such as Io, Vo, and a phase, is indicated on LED by changing a display selection switch, early investigation of the cause of the fault and prompt operation restoration are possible.
The same relay model can respond to the protection for the electric circuit of all classes. Extension and change of an installation place are also easy.
Due to adopting variable setting on Io, Vo and operation time, MDG-A1 type relay can be applicable for any circuit such as incoming feeder and distribution feeder in the high voltage power system.
Moreover, flexibility brought by adoptiong operating condition changeover switch can respond to all high voltage power system protections.
Easy Renewal
Since compatible with the conventional model, renewal to MELPRO-A is easy.
The panel cutouts are the same as the conventional model "E series". It can renew easily, without using an adapter etc. Moreover, compatibility with another conventional model is also high, and then design change can be limitted as the minimum.
Saving of maintenance work
Since the RD type is draw-out type, maintenance is smooth and safe.
Since MELPRO-A relay unit can be pulled out from a switchboard without removing any wiring, therefore, MELPRO-A has a good maintainability. Moreover, in a case side, it has a shortening of CT circuit, then, possible automatically to prevent from CT circuit opening.
