IN162827B - - Google Patents

Abstract

1. Device for monitoring the operating state of thyristors which can be fired with the presence of control signals of a control device, wherein the firing power for the firing signals of each thyristor can be generated by, in each case, a firing circuit (SG1, SG2) which is assigned to the latter and which utilizes the blocking voltage at the respective thyristor, wherein a feedback signal can be released by each firing signal corresponding with the control signal and wherein a protective firing device (SZ1, SZ2) is assigned, in each case, to each thyristor, characterised in that the feedback signals of, in each case, at least two parallel-connected thyristors (T1, T2 or T3, T4), which can be fired with the presence of an, in each case, pertinent control signal, can be supplied in parallel form to a storage arrangement (PS1, PS2) by means of which the feedback signals to be compared can be supplied serially to a detector (D), by means of which : in the event of failure of the feedback signals, a first identifying signal, which indicates the failure of the firing power, can be released ; through which, in the event of failure of the feedback signal of one of the thyristors (T1 to T4), a second identifying signal, which indicates the response of the protective firing device (SZ1, SZ2) assigned to the latter, i.e. said one of the thyristors, can be released ; and through which, with the presence of all the feedback signals, a third identifying signal, which indicates the correct operation, can be released ; and in that a storage arrangement (PS1, PS2) and the detector (D) are linked with a clock unit (TG1, TG2), the clock signals of which control the detector (D).