Control apparatus or system for purged and pressurized enclosures for electrical equipment

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel with valve means for controlling flow of said gas to said enclosure,
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure, and
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• valve means for controlling flow of said gas to said enclosure for pressurization or purging, and
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange solenoid valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said solenoid valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts requiring Type X pressurization or purging,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts requiring Type X pressurization or purging,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• said control system comprising
• means to supply a purging or pressurizing gas to said enclosure at a predetermined pressure,
• adjustable regulating means including a manual operator and pipe fittings providing safe connections,
• means for controlling said gas supply to maintain said predetermined pressure,
• means rendering said gas supply tamper proof to prevent unauthorized adjustment of said predetermined pressure,
• means providing fail-safe, downstream, differential pressure indication responsive to enclosure pressure to indicate pressure to permit adjustment of said valve to predetermine said pressure,
• piping connections to said enclosure from said system,
• means to provide continuous flow of purging and pressurizing gas through said system past said pressure indication means to an atmospheric vent to prevent gas from being trapped therein,
• means to control continuous flow of purging and pressurizing gas through said system past said pressure indication means to vary the flow rate through said system and venting gas to atmosphere,
• means providing color coded indication of said predetermined pressure wherein selected colors indicate low, safe and high pressures, respectively and including means to indicate enclosure pressure in inches of water, and
• a supporting panel supporting said pressure indicating and pressure control means and having indicia for indicating the mode of use and the necessity for use of the system to meet safety requirements.

A control apparatus for a system for purging and pressurization of electrical equipment including

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• said apparatus comprising
• means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control apparatus for a system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• said apparatus comprising
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange solenoid valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said solenoid valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control apparatus for a system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts requiring Type X pressurization or purging,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• said apparatus comprising
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• rapid exchange valve means for controlling flow of said gas for rapid exchange of gas in said enclosure,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to active said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control apparatus for a system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts requiring Type X pressurization or purging,
• means to supply a purging or pressurizing gas to said enclosure at a first predetermined pressure,
• means for venting said enclosure at a second predetermined pressure,
• said apparatus comprising
• automatic means for controlling said gas supply to maintain said first predetermined pressure comprising
• a supporting panel,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to regulate pressure during permit the rapid exchange function,
• automatic valve means for controlling flow of said gas to said enclosure for pressurization or purging,
• pressure indicating means responsive to pressure of said gas to indicate the pressure thereof to permit adjustment of said valve to produce said first predetermined pressure,
• an electronic control unit including
• timing means controlling said valve means, and
• an automatic pressure control switch and alarm responsive to enclosure pressure operable to activate said alarm and deenergize said system and said electrical equipment on predetermined pressure loss in said enclosure.

A control apparatus for a system for purging and pressurization of electrical equipment comprising

• an enclosure in a hazardous area containing combustible gases, vapors or dusts, or in danger of containing combustible gases, vapors or dusts,
• said enclosure having electrical equipment therein endangered by said combustible gases, vapors or dusts,
• said control system comprising
• means to supply a purging or pressurizing gas to said enclosure at a predetermined pressure,
• adjustable regulating means including a manual operator and pipe fittings providing safe connections,
• said apparatus comprising
• means for controlling said gas supply to maintain said predetermined pressure,
• means rendering said gas supply tamper proof to prevent unauthorized adjustment of said predetermined pressure,
• means providing fail-safe, downstream, differential pressure indication responsive to enclosure pressure to indicate pressure to permit adjustment of said valve to predetermine said pressure,
• piping connections to said enclosure from said system,
• means to provide continuous flow of purging and pressurizing gas through said system past said pressure indication means to an atmospheric vent to prevent gas from being trapped therein,
• means to control continuous flow of purging and pressurizing gas through said system past said pressure indication means to vary the flow rate through said system and venting gas to atmosphere,
• means providing color coded indication of said predetermined pressure wherein selected colors indicate low, safe and high pressures, respectively and including means to indicate enclosure pressure in inches of water, and
• a supporting panel supporting said pressure indicating and pressure control means and having indicia for indicating the mode of use and the necessity for use of the system to meet safety requirements.