- Self-Power Design: Starting from 10% / 20% of the Load current as per model selection.
- Two sets of protection setting groups
- Energy pulse output tripping 24V@0.4Ws
- DEFT & Inverse characteristics for O/C and E/F, individually selected for phase & earth fault
- 2 Optically isolated digital inputs for Remote Trip, Protection blocking
- 4 Digital Output contacts for annunciation
- Relay gets energised either from Current, Aux. voltage, Front USB (whichever is available)
- Last 5 Fault and 10 Event records with Date & Time stamp
- USB port for data downloading/uploading via PC / Laptop
- RS-485 port with communication protocol of IEC 103 or MODBUS for SCADA communication
- Wide operating range of the Aux supply voltage (AC/DC)
- Battery Free Environment friendly Product
- In-built energy harvesting power backup works in the absence of Aux / Load current to energise the Display/LCD.

Innovative Self Power Protection Relay for RMUs drawout : CSDPR-V2-400
FEATURES
In the family of protection relays, CSDPR-V2-400 is a numeric multi-powered Overcurrent relay specially designed for ring main units & feeder protection. It consists of all the necessary protection and monitoring functions required for RMU. The advanced Controller continuously monitors line load current and E/F currents with standard CTs. These measured values are then used for different protection functions such as IDMT / DT overcurrent protection, E/F protection, Cold load pickup etc. Metering is available on LCD display. The power module derives power from the current flowing through the line; therefore external power supply is not required. Relay provides pulse output to Trip the RMU or compact CB having low low-energy series tripping coil. Along with that, Relay provides potential-free output contacts for Alarm/Annunciation.
The C&S Electric CSDPR-V2-500 self-powered relay offers significant benefits in reliability and cost-effectiveness by eliminating the need for an external auxiliary power supply for core protection functions, which is crucial for applications like Ring Main Units (RMUs).
- The primary advantage is, Relay draws its operating energy directly from the current transformers (CTs) in the protected circuit, ensuring continuous operation even during a main power outage or auxiliary supply failure.
- It can also be energised from an auxiliary voltage supply (AC/DC), an internal battery, or a front USB port (for configuration), providing flexibility during commissioning and maintenance.
- The device is designed to store enough energy to trip the circuit breaker even with low current faults
- It integrates various protections in a single compact unit, including:
- Over-current (O/C)
- Short-circuit (S/C)
- Earth fault (E/F) and Earth fault high set
- Cold load
- Harmonic blocking
- Unbalance/Asymmetric protection
- Circuit Breaker Failure Protection
- The relay stores the last several fault and event records with a date and time stamp.
- Its small and compact design facilitates integration into Ring Main Units and other space-constrained switchboards.
- Features an RS-485 Modbus communication port (rear) and a front USB port for PC/laptop interfacing, enabling remote monitoring, control, and easy configuration using software like CSE LIVELINK.
- An LCD display and push buttons allow for easy viewing of measured parameters, fault data, and setting adjustments.