Ashida ADR141C - Protection Features Overview; Main Protection Functions; Over Current and Earth Fault Element; Relay Design Features

NUMERICAL OC/EF PROTECTION RELAY ADR141C/241C
ASHIDA Electronics Pvt. Ltd.
Ref: Manual / ADR141C / 241C
Issue: 04D
Date : 10.07.2014
Page 7/86
2. Protection Features:
9 4 Element (3 Phase + EF) Non Directional Over current IDMT/DMT.
9 Selection of Curve: Five selectable curve (Normal Inverse1 (C1), Normal Inverse2, (C2)
Very inverse (C3), Extremely inverse (C4), Long time inverse (C5)) and Define Time (C6)
9 Instantaneous Over-Current Protection with adjustable timer.
9 Breaker Failure detection.
9 In-built CB Trip Circuit Supervision function during pre closing and post closing of CB.
9 On site CT Secondary selection 1A or 5A.
9 Internal calculation of zero seq. current (3Io) for Earth fault.
9 Wide range Power supply input 18V to 250V AC/DC.
9 Cold Load Pickup.
9 RS485 communication Port with IEC 60870-5-103 protocol. [Only in ADR241C]
3. Relay Design Features:
9 16 x 2 LCD Backlit display for Parameter and setting display.
9 Online display of CB status and other digital and logical status.
9 Continuous monitoring of module’s internal hardware and alarm generation in case of
failure of any critical components.
9 4 Digital Output contacts for local alarm as Trip.
9 2 dedicated status input for Trip Circuit Monitoring.
9 8 nos of Fault data stored with keypad interface and time stamping.
9 16 Nos. of Event Log provided.
4. Main Functions:
The ADR141C are having following protection functions.
1. Non Directional phase Over current element. (Ip>, and Ip>> )
2. Non Directional 3Io (Internally derived EF) (3Io> and 3Io>>).
3. Trip Circuit Super vision.
4. Breaker Failure Detection.
5. Monitoring Functions.
Each of these functions are independently programmable and can be enable or disable by
user depending upon requirement.
4.1 Over Current & EF Element:
The ADR141C is member of Ashida Numerical Relay family design for protection general
feeder. The relay has one stage of IDMT/DMT setting and one stage of instantaneous setting.
(Ip>, IP>>, 3Io>, 3Io>>). All major international IDMT curves are available. Range for first
stage is 10% to 250% and 50% to 3000% for instantaneous stage for phase and 3Io.
Although the curves tend towards infinite when the current approaches Is (general threshold),