GB1231973A - - Google Patents

Abstract

1,231,973. Automatic exchange systems. SIEMENS A.G. 28 March, 1969 [29 March, 1968], No. 16352/69. Addition to 1,058,893. Heading H4K. The " short circuit " or " short cut " connection used in the switching network described in the parent Specification is made by operating two relays in the same column of the co-ordinate array. To set up a required connection all the relays arranged in the intersecting row and column are reset and the particular relay set up. This procedure is then repeated for the second connection except that the column relays are not reset. In operation marker contacts Z1 and 2S2 are operated if the respective row and column are not busy and the pairs of contacts 13, 14; 23, 24; 33, 34 and 43, 44 operated to reset the row, the column, the relay itself and finally to set the relay respectively. In order to set up a second relay in column 2, the respective line marker contact Zn (Z1 is now open) is operated and the row relays reset by closing contacts 13, 14. Contacts 23, 24 are not operated and the sequence then continues as before with the closure of contacts 33, 34 and 43, 44 to set up relay Kn2. The contacts 23, 24 are prevented from operating by use of the controller shown in Fig. 5 where a pulse emanating from Pr1 can be diverted to Pr3 when an inhibiting signal is applied at KW. In a modification of the system, Fig. 4 (not shown) each relay operating coil may be connected in series with a varistor and only a single column line connection is required. Specification 1,227,056 shows a similar arrangement for operating relay switches.