Grounding relay dd-1/60

Series models

DD-1/40 Grounding relay ;

DD-1/50 Grounding relay ;

DD-1/60 Grounding relay ;

One 、 purpose

DD-1 Type a grounding relay is an overcurrent relay with instantaneous action , It is used as grounding zero sequence overcurrent protection for high-voltage three-phase alternator and motor in small current grounded power system . The relay coil is connected to the zero sequence current transformer ( Cable type 、 Busbar type ） Or zero sequence current protection composed of three phase current transformers . When the zero point of the protected motor is grounded through impedance, the relay is connected to the differential circuit of the converter . When the relay is connected to the zero sequence current filter composed of three current transformers , Locking relay shall also be connected , To prevent possible maloperation caused by unstable current due to external through short circuit .

Two 、 Main technical parameters

Setting range of relay action current and coil impedance value .

Relays of various specifications , When the coils are connected in series or in parallel , Its impedance angle is +35°.

Rated current ：100mA、 frequency 50Hz.

Set the scale error ： No more than ±6%.

Action value becomes worse ： No more than 6%.

Return coefficient ： Not less than 0.5.

Power consumption ： When the setting current is small, it shall not be greater than 0.015VA.

Action time ： stay 1.2 When times the setting current , The action time shall not be greater than 0.3s;3 When times the setting current , The action time shall not be greater than 0.1s.

Contact capacity ： The voltage is not greater than 250V, The current is not greater than 0.5A when , The breaking capacity of relay contact is in DC inductive load circuit （ The intermediate constant is 5±0.75ms） by 20W,

In the AC circuit 100VA.

Medium strength ： The insulation between the relay circuit and the enclosure metal shall withstand AC 50Hz, voltage 2000V after 1min Without breakdown or flashover .

3、 ... and 、 Internal wiring diagram and external wiring diagram

Ordering instructions ：

The relay model and specification must be indicated when ordering 、 Power supply mode and setting range of auxiliary power supply 、 Structural form code 、 Wiring mode before or after the board 、 Quantity and other requirements .

“ The coil of grounding relay is connected to zero sequence current transformer （ Cable type 、 Busbar type 、 Or a zero sequence current filter composed of three phase current transformers ）. When the zero point of the protected motor is grounded through impedance, the relay is connected to the differential circuit of the converter . When the relay is connected to the zero sequence current filter composed of three current transformers , Locking relay shall also be connected , To prevent possible maloperation caused by unstable current due to external through short circuit .”

Shanghai Joseph relay business department