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Copyright This document and parts thereof must not be reproduced or copied without written permission from Hitachi Energy, and the contents thereof must not be imparted to a third party, nor used for any unauthorized purpose. The software and hardware described in this document is furnished under a license and may be used or disclosed only in accordance with the terms of such license.
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This document has been carefully checked by Hitachi Energy, but deviations cannot be completely ruled out. In case any errors are detected, the reader is kindly requested to notify the manufacturer.
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Directive 2004/108/EC) and concerning electrical equipment for use within specified voltage limits (Low-voltage directive 2006/95/EC). This conformity is the result of tests conducted by Hitachi Energy in accordance with the product standard EN 60255-26 for the EMC directive, and with the product standards EN 60255-1 and EN 60255-27 for the low voltage directive.
When two X.21 LDCM is directly communicating with each other one must be set as a master generating the synchronization for the other (the slave). The DTE Signal Element Timing is created from the internal 64 kHz clock. The Byte Timing signal is not used in Hitachi Energy devices. 5.4.4 Technical data...
(slave) IEC18000099-1-en.vsdx IEC18000099 V1 EN-US Figure 69: PDH Communication structure using PCM with X.21 Contact your local Hitachi Power grids representative for more details about C37.94 to X.21 converters. PDH telecommunication via C37.94 interface to transceiver 21-216 5.5.1 Communication requirements GUID-1BF17CA3-93F5-4661-9695-368FE7F359E2 v1 A PDH telecommunication network set-up can be done via 64 kbit/s C37.94 interface to transceiver...
Testing encompasses both fibre-optic and galvanic cable loop-backs depending on their actual positions in the communication network (see Figure 89). Loop-back testing with X.21 galvanic interface requires special procedures and equipment. Contact your local Hitachi Power grids representative for more details. Procedure: Block the trip circuits.