Patent ID: 8515697
Filing Date: 2013-08-20
Classification: B61L

Abstract:
1. A monitoring apparatus for determining a state of an item of railroad wayside signaling equipment having a plurality of signaling elements, the monitoring apparatus comprising: a first vital processing unit; a second vital processing unit separate and diverse from the first vital processing unit; a current sensing unit having a first current sensor and a second current sensor, the first current sensor and the second current sensor each being configured to measure a current being provided to one or more of the plurality of signaling elements; and means for measuring a plurality of voltage levels, each of the voltage levels being a voltage level being supplied to a respective one of the plurality of signaling elements; wherein the first vital processing unit receives a first current measurement from the first current sensor and each of the measured voltage levels, wherein the second vital processing unit receives a second current measurement from the second current sensor and each of the measured voltage levels, and wherein the first vital processing unit and the second vital processing unit are each programmed to determine based on one or more of the first current measurement, the second current measurement and the measured voltage levels: (i) the state of the item of railroad wayside signaling equipment, (ii) failures within the item of railroad wayside signaling equipment, and (iii) failures within the monitoring apparatus itself.