Reliability and workability test apparatus for an environmental monitoring system
US4962368A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1989 |
| Grant date | Oct 9, 1990 |
| Priority date | — |
| Expiry date | May 4, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B26/002
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An environmental monitoring system in which a controller is arranged to test the workability and reliability of a plurality of detector units on a cyclic basis. Each unit has an analog sensor and an analog to digital converter for converting the analog sensor voltage to a digital value in a range of 0 to N. Each unit responds to a test instruction to cause the sensor analog output to assume an alarm value. The sensor output is limited to a maximum value that under a no drift condition of the analog to digital converter, its corresponding digital signal value will be intermediate a tolerance range of values, the upper limit of such range being less than N. The controller includes a test routine program for both issuing the test instruction and for determining if the digital signal test value is within the tolerance range and issuing a trouble output indicative of the test value being outside the range. The controller also includes a polling program which directs the polling of the detector units such that a test instruction is sent sequentially to the detector units on successive loop polls, where a loop poll is one poll of all the units coupled to the line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.