Patent ID: 8698353
Filing Date: 2014-04-15
Classification: G05B

Abstract:
1. A method for operating a redundant system for supplying a load with a voltage, a first output voltage being connected by a first output of a first output module and a second output voltage being connected by a second output of a second output module, to control a load, the method comprising: performing, by a first measurement device included in the first output module, a first test of a first electrical current path at the first output through the load and performing, by a second measurement device included in the second output module, a second test of a second electrical current path from the second output through the load; switching off one of the first or second output voltages of one of the first and second output modules if a result of an associated one of the first and second tests is that a measured value of the current of a respective one of the first and second electrical current paths is below a threshold value; performing, by a read-back input connected to the first and second outputs, a binary test in the one of the first and second output modules, the binary test delivering a logical one if the voltage is still present at a respective one of the first and second outputs and delivering a logical zero if no voltage is present at the respective one of the first and second outputs; the read-back input generating, if a logical zero is delivered, an error message and continuing, if a logical one is delivered, the binary test in cycles for a predetermined duration of a wait time; within the duration of the wait time, operating the other of the first and second output modules having the output voltage still switched on such that the output voltage thereof is switched off; registering the switching off of the other one of the first and second output modules by the one of the first and second output modules performing the binary test and switching, in response to the registering, the output voltage of the one of the first and second output modules back on to assume supplying the load over the associated one of the first and second electrical current paths; and performing a test by the measurement device associated with the other of the first and second output modules after switching the output voltage thereof back on to determine whether a current is flowing and, in an event of no current flowing, generating an error message.