Remote calibration system
First Claim
1. Apparatus for remote calibration of combustible gas measurement apparatus or the like comprising a sealed sensor transmitter unit and a remotely located control apparatus for said unit, said sensor transmitter unit comprising means for detecting the presence of combustible gas and for transmitting an output signal responsive to the concentration thereof to said remotely located control apparatus, means for determining whether said output signal is within a predetermined operative signal range, and for transmitting a sensor fault signal to said remotely located control apparatus, zero calibration input channel means for generating and transmitting a zero calibration initiating signal to said remotely located control apparatus in response to an externally applied activation signal, span calibration means for generating and transmitting a span calibration initiating control signal to said remotely located control station in response to an externally applied activation signal, and means for receiving an acknowledgement signal from said remotely located control station, and said remotely located control apparatus comprising means for receiving said output signal, zero signal and span signal, means for transmitting an acknowledgement signal to said sensor unit, and means for storing zero and span response calibration values of said sensor unit upon initiation of respective zero and span calibration cycles by said zero calibration means and span calibration means.
3 Assignments
0 Petitions
Accused Products
Abstract
Methods and apparatus for remote calibration of combustible gas detectors in which calibration initiation signals are applied to a sealed, explosion-proof sensor assembly to effect a remote calibration sequence and storage of calibration factors.
106 Citations
10 Claims
- 1. Apparatus for remote calibration of combustible gas measurement apparatus or the like comprising a sealed sensor transmitter unit and a remotely located control apparatus for said unit, said sensor transmitter unit comprising means for detecting the presence of combustible gas and for transmitting an output signal responsive to the concentration thereof to said remotely located control apparatus, means for determining whether said output signal is within a predetermined operative signal range, and for transmitting a sensor fault signal to said remotely located control apparatus, zero calibration input channel means for generating and transmitting a zero calibration initiating signal to said remotely located control apparatus in response to an externally applied activation signal, span calibration means for generating and transmitting a span calibration initiating control signal to said remotely located control station in response to an externally applied activation signal, and means for receiving an acknowledgement signal from said remotely located control station, and said remotely located control apparatus comprising means for receiving said output signal, zero signal and span signal, means for transmitting an acknowledgement signal to said sensor unit, and means for storing zero and span response calibration values of said sensor unit upon initiation of respective zero and span calibration cycles by said zero calibration means and span calibration means.
-
8. A method for remotely calibrating the output signal of a combustible gas detector or the like comprising the steps of;
-
applying an external zero calibration initiation signal to a receiver for said zero calibration initiation signal contained in an explosion proof enclosure and transmitting a zero calibration signal to a remotely located control station; measuring the combustible gas concentration at a sampling location and transmitting an ouput signal representing zero combustible gas concentration to said remotely located control station as a zero calibration factor; detecting the stability of said zero output signal and storing the value of said signal upon said stability detection, to represent zero baseline response of the detector; applying an external span calibration initiation signal to a receiver for said signal contained in an explosion-proof enclosure and transmitting to said control station a calibration initiation signal; measuring at said location the concentration of a known calibration gas containing a predetermined concentration of combustible gas for transmitting to said remotely located control station and transmitting an output signal representing said known concentration of combustible gas; and storing the value of said predetermined concentration signal as a span calibration factor. - View Dependent Claims (9, 10)
-
Specification