left of curve Trip or clear on and to right of curve All devices should be considered at same voltage 18 . 4. Extremely Inverse Time Overcurrent and Earth Fault Relay A high set overcurrent unit (type CAG) can be fitted in the same case to provide instantaneous protection under maximum short circuit conditions (see Application Sheet R-5087). This is depicted for five of the ST settings as a dashed-horizontal line. Trip Curve: IEC 60255 Standard Inverse IEC 60255 Very Inverse IEC 60255 Extremely Inverse IEC 60255 Long-Time Inverse IEEE Moderately Inverse IEEE Very Inverse IEEE Extremely Inverse US CO8 Inverse US CO2 Inverse This curve is shown as a multiple of the PICKUP setting (I). All Relays Have An Extremely Inverse Working Curve Inverse Curve : T : 80 Trs / Margin = 0.35 Sec. Many factors impact the absolute value of C t besides the concentration of the target. The TimeDial setting combined with SHORT PU and SHORT TIME setting (shown in heavy lines) depict the IEC-C response. Notes: 1. selected curve at a specified value of current between 2 and 30 multiples of the pickup setting. Fault Detection Use multiple inverse curves to coordinate with down-stream reclose fast and delay curves. Protection relays type Sepam 2000 or Sepam 40/80 make use of a different IDMT formula in which the time multiplier setting is replaced by a set time in seconds. Notes: 1. B Ins / Mara Setting : 100% 500/5A 400/5A 200/5A 100/5A YAA + XV +++ T 1.292 .622 11.99 + 4.422 2.222 A. Response: Extremely Inverse & Short Delay Trip This curve is for 50Hz or 60Hz applications. Time Dial: 3 Tap Multiple: 2 Curve Characteristic Op Time Rst Time (sec) (sec) U1 Moderately Inv 2.303 1.080 U2 Inverse 6.490 5.950 U3 Very Inverse 4.169 3.880 U4 Extremely … This curve is shown as a multiple of the PICKUP setting (Ir). IEEE Extremely Inverse, Short Delay Flat Time-Phase Current Characteristic Curve based on I r for Magnum DS and Magnum SB Circuit Breakers 70C1040 IEC-A Normal Inverse, Short Delay Flat Time-Phase Current Characteristic Curve based on I r for Magnum Circuit Breakers 70C1031 Schneider equivalent time setting. The time lever settings are selected so that all relays operate in 0.2 sec at 20 times the tap setting. The Extremely Inverse portion of the of the curve will be no faster than the Short Time Setting. IDMT Relay Low Current setting: Over Load Current setting is 125%, Plug setting of Relay is 0.8 Amp and Time Delay (TMS) is 0.125 Sec, Relay Curve is selected as Normal Inverse Type. Tap Multiple: Op Time: Curve U1 U2 U3 U4 U5 Characteristic Moderately Inv Inverse Very Inverse Extremely Inv Short-Time Inv 5 SEL-351S relays pdf manual download. There are standard inverse, very inverse and extremely inverse … This curve is shown as a multiple of the PICKUP setting (Ir). In early electromechanical relays the curve is set by means of a dial. 3. U4 (extremely inverse) U5 (short-time inverse) U1 Moderately Inverse Curve M = multiples of pickup I P = max phase current M = I P / 51P1P Time dial shifts curve up / down (slower / faster) • Standard U.S. curves (U1–U5) • Standard IEC curves (C1–C5) • Recloser curve: Trip Curve 3000TC0704 01/2008 LaVergne, TN, USA IEC-EIT + EIT-C-10PU (1) Extremely Inverse Time 3000TC Electrical equipment should be installed, operated, serviced, and maintained only by qualified personnel. The TimeDial setting combined with SHORT PU and SHORT TIME setting (shown in heavy lines) depict the IEEE Extremely Inverse … The most common three types of inverse curves used are: Dr Audih alfaoury 8 o Standard inverse (SI) o Very inverse (VI) o Extremely inverse (EI). The transformer inrush current is also plotted a single point on the TCC diagram. Inverse-time overcurrent element settings include a wide and continuous pickup current range, continuous time-dial setting range, and time-current curve choices from both US (IEEE) and IEC standard curves shown in Table 3. The TimeDial setting combined with SHORT PU and SHORT TIME setting (shown in heavy lines) depict the IEEE Extremely Inverse response. 70C1040 - IEEE Extremely Inverse, Short Delay Flat shorter time than normal. It is a used for sw Manual operation load break switch RPS type pole mounted SF6 gas type load break switch is equipped with very simple and reliable mechanism with is operated by a single spring rotate type mechanism, which we call it manual type. No responsibility is assumed by Schneider Electric for any consequences arising out of Calculate The Short-circuit Current In Each Bus. Thus, the setting is called the “time dial setting - TDS”. The amount of time delay reduction is inverse to the amount of time that has elapsed since the previous overload. 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