Directional Over current and Directional Earth Fault Recloser Control Relay Block 7SR22 With (0NO+3NC)

Features and technical specifications:

1. Motor Protection
2. CT inputs : 4 No’s
3. VT inputs : 4 No’s
4. Binary inputs : 13 No’s
5. Binary output’s : 14 No’s
6. LED : 8 No’s
7. External DC power supply required
8. RS 485 Communication Port

1. Power Supply Unit (PSU) :-

The relay PSU can be directly connected to any dc supply via a suitably rated fuse from 30V dc to 220V dc. In the event of the supply voltage level falling below the relay minimum operate level the PSU will automatically switch itself off and latch out – this prevents any PSU overload conditions occurring. The PSU is reset by switching the auxiliary supply off and on.

2. Current Inputs:-
Four current inputs are provided on the Analogue Input module. Terminals are available for both 1A and 5A inputs.
Current is sampled at 1600Hz for both 50Hz and 60Hz system frequencies. Protection and monitoring functions of
the relay use either the Fundamental Frequency RMS or the True RMS value of current appropriate to the individual function. The waveform recorder samples and displays current input waveforms at 32 samples per cycle (1600Hz).

3. Voltage Inputs:-
Four voltage inputs are provided on the Analogue Input module. Voltage is sampled at 32 samples per cycle (1600Hz) both 50Hz and 60Hz system frequencies. Protection and monitoring functions of the relay use fundamental frequency voltage measurement. The waveform recorder samples and displays voltage input waveforms at 32 samples per cycle (1600Hz). NB: The Relay has a flat frequency response measuring harmonic currents up to and including the 50th Harmonic but does not measure the content at the aliasing frequencies i.e. 800 Hz (16th harmonic) + 1600 Hz (32nd harmonic) + 2400 Hz (48th harmonic).

4. Binary Inputs:-
The binary inputs are operated from a suitably rated dc supply. Relays are fitted with 13, 33 or 43 binary inputs (BI) depending on the variant. The user can assign any binary input to any of the available functions (INPUT CONFIG > INPUT MATRIX). The Power Supply module includes the relay basic I/O incorporating 3 x BI and 6 x BO. Pick-up (PU) and drop-off (DO) time delays are associated with each binary input. Where no pick-up time delay has been applied the input may pick up due to induced ac voltage on the wiring connections (e.g. cross site wiring). The default pick-up time of 20ms provides ac immunity. Each input can be programmed independently. Each input may be logically inverted to facilitate integration of the relay within the user scheme. When inverted the relay indicates that the BI is energised when no d.c. is applied. Inversion occurs before the PU & DO time delay, Each input may be mapped to any front Fascia indication LED and/or to any Binary output contact and can also be used with the internal user programmable logic. This allows the relay to provide panel indications and alarms.

5. Binary Outputs (Output Relays):-
Relays are fitted with 14, 22 or 30 binary outputs. All outputs are fully user configurable and can be programmed
to operate from any or all of the available functions. The Power Supply module includes the relay basic I/O. The module includes six binary outputs each fitted with 1 contact – providing in total 1 x normally closed (NC), 2 x change-over (CO) and 3 x normally open (NO) contacts. In the default mode of operation binary outputs are self reset and remain energised for a user configurable minimum time of up to 60 seconds. If required, outputs can be programmed to operate as ‘hand reset’. Alternatively, outputs can be programmed as ‘Pulsed’ outputs. When operated, these outputs will reset automatically after a delay of the minimum operating time. The binary outputs can be used to operate the trip coils of the circuit breaker directly where the trip coil current does not exceed the ‘make and carry’ contact rating. The circuit breaker auxiliary contacts or other in-series auxiliary device must be used to break the trip coil current. When the relay is withdrawn from the case all normally closed contacts will be open circuited. This should be considered in the design of the control and protection circuitry.