Motor Protection Relay Block 7SR17 With (0NO+5NC)

Features and technical specifications:

1. Motor Protection
2. CT inputs : 4 No’s
3. Binary inputs : 5 No
4. Binary output’s : 8 NO
5. RS485 Communication Port

1. CURRENT INPUTS:-
Current input terminals are available for both 1A and 5A inputs.Current is sampled at 32 samples per cycle (1600Hz for 50Hz and 1920Hz for 60Hz systems). 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.

2. VOLTAGE INPUTS:-
The voltage inputs can be defined with a nominal rating between 40 – 160V. Voltage is sampled at 32 samples per cycle (1600Hz for 50Hz and 1920Hz for 60Hz systems). 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.

3. BINARY INPUTS:-
The binary inputs are opto-couplers and can be operated from a suitably rated supply. The binary inputs are polarity conscious and will not operate if the DC supply polarity is reversed. For consistency and safety it is advised that AC connections for binary inputs are made with the Live connection to the +ve terminal and Neutral connection to –ve.
The user can assign any binary input to any of the available functions (INPUT CONFIG > INPUT MATRIX). 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 voltage is applied. Inversion occurs before the PU & DO time delay.

4. BINARY OUTPUTS (OUTPUT RELAYS):-
All outputs are fully user configurable and can be programmed to operate from any or all of the available functions.
In the default mode of operation binary outputs are self reset and remain energised for a user configurable minimum operate time of up to 60 seconds. If required, outputs can be programmed to operate as ‘hand reset’ or ‘pulsed’. Where an output is programmed to be ‘hand reset’ and ‘pulsed’ then the output will be ‘hand reset’ only. Operating a binary output as ‘hand reset’ fulfils the requirements of ANSI function 86 (Lockout). 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.