The limit of detection data for Cd, Cu, Na and Zn are 3.4, 4.2, 9.2 and 0.9 mg L - 1, respectively. A significant increase in the sensitivity (20%) was found only with the addition of 0.55% (m/v) La solution. Several spectrochemical buffers (citric acid, EDTA, chlorides of Ca, Cs, La, Li, and Na) were studied for improving the sensitivity of the AAS determinations for Cr. All the absorbance maxima are observed in the near cathode region (e.g., in the range of 0.5-1.0 mm from the cathode), while the AA signal smoothly fades towards the anode. The analyte atom distribution along the vertical axis of the conically-shaped ELCAD plasma (height: 3.5 mm) is element specific. A flow injection system was developed and applied to introduce 3 mL of aqueous standards of a set of environmentally relevant metals (Ca, Cd, Cr, Cu, Na, Pb and Zn) into the plasma. For this purpose, the ELCAD cell, placed on a platform adjustable with micrometer screws, was inserted into the optical path of a commercial line-source AAS instrument.
They accept all traditional and modern communication media, i.e. The adjustment to other communication media takes place via media converter. The relays provide optical ports for relay-to-relay (R2R). The readings are available right after fault clearance for quick line clearance and system restoration parallel lines or resistive line faults fed from both line terminals. This results in precise readings, even under difficult system conditions, e.g. Back-up zones provide remote back-up for upstream and downstream lines and other power system componentsĬontrary to traditional measurement approaches, the distance-to-fault locator uses measurement quantities from both line terminals. The high-speed distance relay operates fully independent from the differential relay.
The readings are available right after fault clearance for quickline clearance and system restoration Contrary to traditional measurement approaches, the distance-to-fault locator uses measurement quantities from both line terminals. optical emission spectra eISSN 2397-7264 Received on 4th April 2019 Revised 20th May 2019 Accepted on 29th May 2019 E-First on 5th August 2019 doi: 10.1049/hve.2019. Back-up zones provide remote back-up for upstream and downstream lines and other power system components. Complex system configurations receive clearly defined protection zones and maximum fault coverage. The protected differential zone may be easily extended from 2 up to 6 line ends. The differential protection scheme is fully available in a chain topology.įault locator for one and two terminal measurement for high accuracy on long lines with high load and high fault resistance.Ĭapacitive charge current compensation increases the sensitivity of the differential protection on cables and long lines. In a process control design we work with programmable logic controllers from the following companies: Siemens (Simatic), Saia, Wago, Teco, Amit. Tolerates loss of one data connection in a ring topology (routing in 120 ms).
If the communication method is changed, fl exible retrofitting of communication modules to the existing confi guration is possible.
Elcad optic serial#
The serial protection interfaces (R2R interfaces) of the relays can flexibly be adapted to the requirements of all communication media available. The SIPROTEC 7SD52/53 has the following features:Ģ full-scheme main protections in one unit (differential and distance protection) A special GPS-option allows the use of the relays in communication networks, where the delay time in the transmit and receive path may be quite different. The units measure the delay time in the communication networks and adaptively match their measurements accordingly. Several teleprotection schemes ensure maximum selectivity and high-speed tripping time. The relay also provides a full-scheme and non-switched distance protection as an optional main 2 protection. The relays may be employed with any type of system grounding. Also, transformers and compensation coils within the differential protection zone are protected as are serial and parallel-compensated lines and cables.
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