WO2016164335A1 - Purge systems and purge control methods - Google Patents

Abstract

Purge + pressurization systems and purge + pressurization methods are provided. In one example, a purge + pressurization system includes an enclosure with an interior defining a hazardous location area, and an exterior defining a safe area which is physically isolated from the hazardous location area. The enclosure may include a user equipment (UE). There may be a sensor operatively associated with the enclosure to sense an operating condition of the hazardous location area or the UE. A controller may be located in the safe area, and may be configured to control at least one actuator operatively associated with the enclosure to implement a controlled purge + pressurization process to control an environmental condition of the hazardous location area.

Description

PURGE + PRESSURIZATION SYSTEMS AND PURGE + PRESSURIZATION CONTROL

METHODS

REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to, and the benefit of, U.S. Provisional Patent Application Serial No. 62/143,965, filed on April 7, 2015, entitled PURGE SYSTEMS AND PURGE CONTROL METHODS, the entirety of which application is hereby incorporated by reference.

BACKGROUND

[0002] The following relates to purge + pressurization systems and purge + pressurization control methods.

SUMMARY

[0003] Various aspects of the present disclosure are now summarized to facilitate a basic understanding of the disclosure, wherein this summary is not an extensive overview of the disclosure, and is intended neither to identify certain elements of the disclosure, nor to delineate the scope thereof. Rather, the primary purpose of this summary is to present various concepts of the disclosure in a simplified form prior to the more detailed description that is presented hereinafter. The present disclosure provides purge + pressurization systems and purge + pressurization control methods.

[0004] Disclosed examples include a purge + pressurization system, including an enclosure with an interior defining a hazardous location area, and an exterior defining a safe area which is physically isolated from the hazardous location area. The system further includes a user equipment (UE) located in the hazardous location area, and a sensor operatively associated with the enclosure to sense an operating condition of the hazardous location area or the UE. The system further includes a controller located in the safe area, and configured to control at least one actuator operatively associated with the enclosure to implement a controlled purge + pressurization process to control an environmental condition of the hazardous location area, and a plurality of input/output (I/O) modules communicating with the controller. The plurality of I/O modules includes a first I/O module configured to receive a sensor signal from the sensor, and to provide sensor data to the controller; a second I/O module configured to provide control data from the controller to the actuator; and a third I/O module configured to control power to the UE.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1 is a schematic diagram illustrating an exemplary purge + pressurization system and control room.

[0006] FIG. 2 is a schematic diagram illustrating an enclosure and other equipment.

[0007] FIG. 3 is a flow diagram of a startup procedure.

[0008] FIG. 4 illustrates turning on enclosure power.

[0009] FIG. 5 illustrates turning off enclosure power.

[0010] FIG. 6 illustrates an embodiment of a purge + pressurization system.

[0011] FIG. 7 illustrates another embodiment of a purge + pressurization system.

[0012] FIG. 8 illustrates another embodiment of a purge + pressurization system.

DETAILED DESCRIPTION

[0013] Referring now in more detail to the figures, several embodiments or implementations are hereinafter described in conjunction with the drawings, wherein like reference numerals are used to refer to like elements throughout, and wherein the various features are not necessarily drawn to scale. The present disclosure provides purge + pressurization systems and purge + pressurization control methods. These aspects of the disclosure find utility in association with preventing hazards due to arc flash and electrical sparks. In addition, although illustrated in particular contexts, the disclosed concepts can be employed in any setting where purge + pressurization systems are used.

[0014] FIG. 1 shows purge + pressurization system 100 including two areas: safe area 102 and hazardous location area 103. In practice in certain examples, and enclosure 144 has one or more walls defining an interior including the hazardous location area 103, and the exterior of the enclosure 144 is considered the safe area 102, schematically shown in FIG. 1. The safe area 102 in this example includes a purge + pressurization system controller 112, referred to herein as an Electric Power Control Unit (EPCU). The illustrated EPCU 112 includes an electronic memory 116, a processor 120, and the processor 120 is programmed or otherwise configured to implement purge + pressurization control functionality shown schematically at 128. In general, in one example, the purge + pressurization control processing functions 128 include controlling pressure within the interior of the enclosure 144, and controlling application or discontinuation of power supplied to user equipment 180 in the enclosure 144. For example, the EPCU 112 may perform initial purging or cleanout of the enclosure interior during which a certain amount of air or other supply gas is pumped through the enclosure 144 from an inlet or input valve 160 to an outlet or output vent 148, followed by control in an operating mode or state in which a positive gas pressure is controlled in the enclosure interior within a predefined or adaptive acceptance ranges while power is applied to the user equipment 180. The EPCU 112 then monitors the enclosure interior pressure while the user equipment 180 is powered, and selectively discontinues application of power to the user equipment 180 if the enclosure interior pressure falls outside an acceptance or tolerance range. The EPCU 112 in certain examples selectively discontinues application of user equipment power based on other sensed conditions using sensor data from further sensors within the enclosure 144 or otherwise operatively associated with the enclosure 144. For example, the EPCU 112 may also monitor one or more temperature signals or values obtained from temperature sensors (e.g., an RTD in the example of FIG. 1), and selectively discontinue application of power to the user equipment 180 if the monitored temperature exceeds a predetermined or adaptive threshold limit. In this manner, the EPCU 112 implements a purge + pressurization controls that allows the user equipment to operate when the interior of the enclosure 144 is within a specific environmental range of one or more variables, including without limitation pressure, temperature, power, etc.

[0015] The processor 120 in the illustrated EPCU 112 is further programmed in certain examples to implement trending functionality illustrated schematically at 124 in FIG. 1. In other examples, the EPCU 112 provides sensor data through a wired or wireless communications interface to an external distributed control system (DCS) 104, to facilitate implementation of trending functionality 108 by the DCS 104. Whether implemented in the EPCU 112 and/or in the DCS 104, the trending functionality 124, 108 can include evaluating certain sensor data (e.g., pressure, applied user equipment power, temperature, etc.) for diagnostic and/or prognostic goals. For instance, the trending functionality 124, 108 can evaluate trends or changes in inlet or input gas flow rate as well as enclosure interior pressure to selectively detect degradation or failure in one or more gaskets or other ceiling structures associated with the enclosure 144, and a signal or message can be provided by the controller 112 and/or the DCS 104 to alert a user that maintenance should be scheduled or undertaken. Such warnings or alarms can be done alone or in combination with shutting down the system (e.g., removing applied power from the user equipment 180) or other remedial action. In another example, the trending functionality 124, 108 can include evaluating the current supplied to the user equipment 180 or other power consumption metrics associated with operation of the enclosure and the user equipment 180, with optional system shutdown and/or alarm/warning/message generation to indicate that the user equipment 180 is drawing more power than expected, etc. In another example, the trending functionality 124, 108 can include evaluating inlet and outlet flow rates associated with a valve actuator 160 and a vent actuator 148 to infer or identify potential problems with a vent 148 being stuck in a closed position (e.g., by identifying rising pressure trends and/or decreasing outlet flow rate trends, etc.), lack of responsiveness of a degrading valve actuator 160 (e.g., not responding to changes in control signals or messages provided to the valve actuator 160).

[0016] The EPCU 112 interfaces with the enclosure and associated equipment in one example by a series of I/O modules 132. In certain examples (e.g., FIG. 6 below), the EPCU 1 12 may include on-board VO circuitry, which can be used to interface with sensors and actuators of an associated enclosure 144. In other examples (e.g., FIG, 7 below), the EPCU 112 includes onboard eye/oh circuitry, as well as an interface to a bus system 136 to interface with external I/oh modules 132. Moreover, the EPCU 112 can be configured to implement multiple purge + pressurization control operations in order to control more than one enclosure 144 and associated equipment 180 (e.g., FIG. 7 below). In this regard, the EPCU 1 12 in certain examples sends and receives signals which can include messaging, to and from a bus system 136 to which one or more I/O modules 132 are operatively coupled. The bus system 136 in certain examples includes a power rail, as well as a data bus configuration in order to receive sensor data from one or more sensors related to one or more conditions associated with the enclosure 144 and operation of a purge + pressurization system generally, as well as to provide control messages and/or signals to one or more actuators to implement the purge process. Any number of input/output modules 132 may be connected to the bus system 136. The I O modules 132 may send and receive signals 140. The signals 140 may be analog or digital. The bus system 136 in one example provides communication according a Controller Area Network (CAN Bus) standard, and other implementations are possible, including without limitation an RS-485 standard, or any other suitable standard.

[0017] The hazardous location area 103 in one example includes the enclosure 144, which in turn includes one or more machines or other type or form of user equipment (UE) 180, such as a robot or other machine or system to perform a manufacturing process within the hazardous location area 103. In some embodiments, the UE 180 is a device under test (DUT). The illustrated enclosure 144 includes a vent 148, a general purpose input 152, for example, to facilitate interconnection with certain user equipment signal sources (not shown), as well as a thermocouple, resistance temperature detector (RTD) or other suitable type of temperature sensor 156, a controllable valve actuator 160, a user interface controller (UIC) 164, a contact 168 for controlling application of power to the user equipment 180, and the system may include other sensors 172 and actuators 176.

[0018] The EPCU 112 in certain examples provides operative communicative interfacing with a distributed control system (DCS) 104. For example, the EPCU 112 and the DCS 100 for communicating with one another by one or more suitable wired or wireless communications technologies, and can use any suitable bus structure and associated communication protocol or protocols. In addition, the DCS 104 in certain examples implements trending functionality 108, and the DCS 140 is operable in certain examples to control the EPCU 112. The DCS 104 may be located in a control room 101, for instance, as shown in FIG. 1, in order to allow a user to operate the purge + pressurization system 100 from a remote location via the DCS 100 for communicating with the EPCU 112. The DCS 104 in certain examples communicates with the EPCU 112 via an Ethernet connection, a wireless connection, an RS-485 connection, or any other suitable connection and associated protocol.

[0019] The disclosed techniques and apparatuses advantageously facilitate purge + pressurization of an enclosure 144 that houses a UE 180, whether an operating machine or DUT. When the enclosure 144 is purged, environmental conditions are controlled in the enclosure interior to ensure that any adverse effects of the enclosure interior do not impact the safe area 102. In one example, the user equipment 180 may be used in normal operation to implement a manufacturing process or procedure that requires volatile gas or other condition that is undesirable in the safe area 102. In certain applications, moreover, the user equipment 180 may include high voltage circuitry that could ignite a volatile gas within the interior of the enclosure 144 under certain operating conditions (e.g., excessive internal temperature, etc.). In operation in certain examples, the EPCU 112 implements the purge process in order to ensure that the user equipment 180 is not powered if the environmental conditions inside the enclosure 144 could possibly lead to arc flash, electrical sparks or other adverse conditions within the enclosure 144. User equipment 180 is powered, the EPCU 112 monitors the internal environment of the enclosure 144 and order to ensure that a certain predefined amount of positive pressure is applied to the enclosure 144 (e.g., by controlling an inlet valve actuator 160 to provide a certain amount of supply gas (e.g., 204 in FIG. 2 below) to the enclosure interior. This operation mitigates or avoids the possibility of volatile, noxious or other undesirable gas within the enclosure interior from escaping outside the enclosure 144 into the safe area 102. In this way, the environment of the safe area 102 is maintained.

[0020] Some purge + pressurization systems locate an EPCU inside of a hazardous area location along with an enclosure containing a UE. In the techniques and systems disclosed herein, an EPCU 112 is advantageously located in the safe area 102 which is isolated from (e.g., outside of) the enclosure 144 and the associated interior hazardous location area 103. The concepts of the present disclosure thus facilitate user safety, for example, by reducing the chance that the EPCU 112 itself will create a spark or arc in the hazardous area 103.

[0021] FIG. 2 shows an example enclosure and other equipment to implement a purge + pressurization process to facilitate operation of the user equipment 180 in the interior 103 of the enclosure 144 without adverse impact on the safe area 102 outside the enclosure 144. An EPCU 112 and one or more associated I/O modules 132 (e.g., FIG. 1) exchange signals and/or values via one or more lines 140. The enclosure 144 in this example includes a UIC 164, a valve 160, a vent 148, a UE 180, and a temperature sensor 220. FIG. 2 provides a simplified depiction, and the components are not necessarily restricted to the locations depicted in FIG. 2. For example, the UIC 164 may be located on the outside of the enclosure 144, the inside of enclosure 144, or on the edge of enclosure 144. In another example, a relay 256 may be located on the outside of enclosure 144, the inside of enclosure 144, or on the edge of enclosure 144. A door on the enclosure 144 may be controlled by the EPCU 112 in certain examples, for instance, using a controlled relay or other door lock mechanism operated by an eye/oh module 132 according to a signal from the EPCU 112. [0022] FIG. 2 further shows protective gas supply 204 providing supply gas to an input 140a of the valve 160, which may be controlled by valve control 208. The valve 160 in one example is selectively open or closed in a binary or continuous analog fashion the according to the valve control signal 208 from the EPCU in order to regulate or control input pressure 140b and/or input flow 140c at an inlet (e.g., entrance) to the enclosure 144. In this regard, the valve 160 may include integral sensors for sensing or detecting pressure and/or flow relative to the input gas provided from the supply 204. The vent 148 in one example is controlled by a vent control signal 224 provided through a corresponding I/O module 132 from the EPCU 112, and the vent 148 can be used in certain examples to control the pressure of the enclosure interior 103. In certain implementations, moreover, the vent 148 includes one or more sensors providing an output pressure signal on line 140d, an output flow signal on line 140e and/or a vent temperature signal on a line 140f to the EPCU 112 via the corresponding I/O modules 132. A power source 244 provides power (e.g., supply voltage and associated current flow) to the UE 180 through a relay 256 having contacts to selectively disconnect or connect the power source 244 to the user equipment 180. In addition, the relay 256 operates according to a relay control signal 264 (e.g., provided by the EPCU 1 12 using an associated I/O module 132, there the relay 256 implements the contact 168 shown in FIG. 1 above). A current sensor 260 is connected and used as shown to sense the current flow to the user equipment 180 and to provide a corresponding sensor signal (via a corresponding I/O module 132) to the EPCU 112 representing the user equipment current. In other examples, the relay 256 can be connected and used at any other applicable point in the diagram (e.g., the relay 256 can be located in the interior 103 of the enclosure 144). Relay control 264 may control the relay 256. Temperature sensor 220 may provide temperature signal 140L

[0023] FIG. 3 is a flow diagram of a startup procedure. With reference thereto, process 300 may be implemented by the EPCU 112. At 304, the system is powered on. At 308, parameters are initialized such as Ethernet, Wi-Fi, Bluetooth, NFC and/or RS 485 parameters. At 312, a user may configure purge + pressurization system parameters such as enclosure volume, and volume exchange, whether the controller 112 is implementing a gas or dust-based purge + pressurization process, pressure and/or flow control ranges, temperature ranges, power (e.g., current) ranges, etc. At 320, the purge + pressurization process enters a steady state and a small amount of positive enclosure gas pressure (e.g., above a predetermined threshold value stored in the EPCU memory 116) is continuously applied, which may continue to be applied even after 320 is completed. At 324, The EPCU 112 measures (e.g., obtains via sensors and corresponding I/O modules 132) one or more enclosure environmental parameters, and the EPCU 112 determines at 328 whether the parameters are acceptable. If not (NO at 328), the process 300 returns to 324. For example, if a temperature is judged not to be acceptable, or the enclosure interior pressure is not within the configured acceptance range, the process 300 returns to 324. Once the parameters are acceptable (YES at 328), the EPCU 112 determines whether a gas or dust process should be implemented at 332. If a gas process is to be implemented (GAS at 332), a gas remedy operation (e.g. start purging the enclosure) is implemented at 336. In one implementation, this may include applying pressure to pump or transfer at least 4-5 times the enclosure volume through the enclosure 144 in order to purge + pressurization hazardous air. If a dust process is to be implemented (DUST at 332), a dust remedy operation (e.g. clean out enclosure) is implemented at 340. After either 336 or 340, the process 300 continues at 344, where the EPCU 112 determines whether the remedy was successful and pressurization is acceptable. If so (YES at 344), power to the enclosure is engaged at 348, and the process 300 returns to 344. If not (NO at 344), power is shut off at 346 and the process 300 returns to 324).

[0024] FIG. 4 illustrates turning on enclosure power. In one implementation, the sequence diagram 400 may be an example of processing at 344 or 348 in FIG. 3. 404-432 show various determinations being made, each of which is required for the EPCU 1 12 (FIG. 2) to turn on the relay 256 to power the UE in the hazardous location area in one example. In other examples, the EPCU 112 evaluates any suitable set of conditions (e.g., a subset of those shown in FIG. 4) before applying power to the user equipment 180 in the enclosure 144. In the illustrated example, the EPCU 112 makes the determination by evaluating sensor data received from one or more sensors associated with the enclosure 144 (e.g., via one or more corresponding I/O modules 132 in FIG. 1). At 404, the EPCU 112 determines whether an immediate shutdown input (e.g., of the UI controller 164 or a separate emergency stop or E-stop button) is off/disabled. At 408, the EPCU 1 12 determines whether an overload is off/disabled. At 412, the EPCU 112 determines whether a temperature is less than a maximum, such as a predetermined value stored in the memory 116 of the EPCU 112. At 416, the EPCU 112 determines whether a pressure is less than a maximum. At 420, the EPCU 112 determines whether a flow is greater than a minimum. At 424, the EPCU 112 determines if a pressure is greater than a minimum. In 428, the EPCU 1 12 determines whether there is no system fault. At 432, the EPCU 112 determines whether critical settings are not changed. If the preconditions have been met at 404-432, the EPCU 112 begins the purge + pressurization process at 436. At 440, the EPCU 112 starts a timer. At 444, the EPCU 112 determines whether a first lock is on or unused. 448 shows auxiliary relay 1 lock door. 452 shows auxiliary relay 1 energized. If the EPCU 112 verifies that the conditions in 444, 448 and 452 are satisfied, the enclosure door is deemed to be secured at 460. 456 shows bypass before purging on. If the condition at 456 is satisfied, the EPCU 112 determines at 464 that conditions are safe for applying power to the user equipment 180. The EPCU 112 determines at 468 whether an input is used for the enclosure power relay (e.g., relay 256 in FIG. 2), and the EPCU 112 turns the enclosure prior relays on at 472.

[0025] FIG. 5 illustrates turning off enclosure power. In various implementations, the sequence diagram 500 may be an example of processing at 344 or 346 in FIG. 3. In this example implementation, the EPCU 112 evaluates sensor data obtained from the purge + pressurization system via corresponding I/O modules 132 to determine if one or more conditions exist (e.g., at 504, 508, 512, 516, 520, 524, 528, 532 in FIG. 5) and selectively discontinues application of power to the user equipment 180 inside the enclosure 144 based on certain detected conditions. At 504, the EPCU 112 determines whether a control power relay input is broken and/or shorted, and if so operates or controls the relay (e.g., relay 256 in FIG. 2 above) at 536 to remove power from the user equipment 180 before a system restart is undertaken at 560. At 508, the EPCU 112 determines whetheran immediate shutdown input broken/shorted. At 512 the EPCU 112 determines whether an immediate shutdown input is on. If either the conditions at 508 or 512 are met, the EPCU 112 implements an immediate shutdown at 540. At 516, the EPCU 112 determines whether an overload input is broken/shorted, and the EPCU 112 determines whether an overload input is on at 520. If either of the conditions at 516 or 520 are met, the EPCU 112 determines that there is an overload at 544, and starts or and enables a timer at 548. Once the timer expires, the EPCU implements a bypass operation at 556, and then restarts the system at 560. At 524 the EPCU 112 determines whether the enclosure pressure is less than a minimum (e.g., a predetermined value stored in the memory 116). At 528, the EPCU 112 determines whether a system fault has been detected. If either of the conditions is 524 or 528 are met, the EPCU 112 starts or enables the timer at 548, and implements the bypass operation at 556. At 532, the EPCU 112 determines whether critical settings are not changed. If the critical settings have been changed at 532, the EPCU 112 implements the system restart at 560. At 552, the EPCU 112 determines whether a bypass before purging parameter has changed from ON to OFF. The EPCU 112 implements the system restart at 560 if the conditions in either of 532 or 552 are met, or if any of 536, 540 or 556 happen. After a system restart at 560, the EPCU 112 turns off the power at 564. At 568, the EPCU 112 determines if and enclosure power relay input is used, and if so turns the control power relays off at 572.

[0026] FIG. 6 illustrates an embodiment of a purge + pressurization system 600, in which a UIC 604 is operatively associated with the EPCU 112 in the safe area 102, and the UIC 604 may be operated by a user to control the EPCU 112. The EPCU 112 includes an auxiliary (aux) 1 output 608 and an auxiliary 2 output 612. In addition to the above-described features and functions, the EPCU 112 in FIG. 6 controls various components of the enclosure 144 such as a second vent 616 and second RTD 624. As illustrated in FIG. 6, the EPCU 112 is operable to control the components of the enclosure 144 without the use of an external bus system. In other words, the illustrated EPCU has on-board I/O modules or circuitry, and the EPCU 112 may control any number of enclosures 144 in this manner to implement one or more purge + pressurization processes.

[0027] FIG. 7 illustrates another embodiment of a purge + pressurization system 700, in which the EPCU 112 controls components associated with a first enclosure 144a, including a vent 148a, an input 152a, an RTD 156a, a UIC 164a, a contact 168a, the user equipment or UE 180a, and a valve 160a. The EPCU 112 in this example controls the components associated with the first enclosure 144a and the corresponding first purge + pressurization process without the use of an external bus system. Although the EPCU 112 in FIG. 7 controls the components of only one enclosure 144a without the use of an external bus system, the EPCU 112 may control any number of enclosures in this manner, and can be equipped with on-board I/O circuitry or modules to accommodate any number of controlled purge + pressurization processes and associated enclosure equipment. As further illustrated in FIG. 7, the EPCU 112 controls a second purge + pressurization process by controlling components associated with a second enclosure 144b. These components may include a vent 148b, an input 152b, a valve 160b, a UIC 164b, contacts 168b, 168c, a UE 180b, and an RTD 156b. The EPCU 112 controls these components through the use of bus system 136 and I/O modules 132a-132g. The illustrated VO modules include a vent # 132a, an input # 132b, a valve out 132c, a UIC 132d, an aux out # 132e, an end count # 132f, and a temp input 132g. Although the illustrated EPCU 112 controls the components of only a single enclosure with the use of a bus system 136, the EPCU 112 may control any number of enclosures in this manner.

[0028] FIG. 8 illustrates another embodiment of a purge + pressurization system 800, including a first EPCU 112a located in a safe area controls second EPCU 112b and third EPCU 112c, which may alternatively be referred to as sub- controllers. The second EPCU 112b has a first hazardous area 103 a, and controls components of a first enclosure 144a. The third EPCU 112c has a second hazardous area 103b and controls components of second enclosure 144b. Although the illustration shows the first EPCU 112a controlling only the second EPCU 112b and the third EPCU 112c, the first EPCU 112a may be used to control any number of other EPCUs. In this manner, a single EPCU 112 can be used to implement multiple purge + pressurization control processes via the functionality 128 in the first or main EPCU 112a, and to communicate via wired or wireless communications connections to the sub- controllers 112b and/or 112c to control the local operation of the actuators and/or sensors individually associated with the corresponding enclosures 144a and 144b.

[0029] The above examples are merely illustrative of several possible embodiments of various aspects of the present disclosure, wherein equivalent alterations and/or modifications will occur to others skilled in the art upon reading and understanding this specification and the annexed drawings. In particular regard to the various functions performed by the above described components (assemblies, devices, systems, circuits, and the like), the terms (including a reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component, such as hardware, processor-executed software, or combinations thereof, which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the illustrated implementations of the disclosure. In addition, although a particular feature of the disclosure may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Also, to the extent that the terms "including," "includes," "having," "has," "with," or variants thereof are used in the detailed description and/or in the claims, such terms are intended to be inclusive in a manner similar to the term "comprising." [0030] In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense. In addition, the reference numerals in the drawings do not necessarily imply any specific order.

Claims

CLAIMS The following is claimed:

1. A purge + pressurization system, comprising:

an enclosure with an interior defining a hazardous location area, and an exterior defining a safe area which is physically isolated from the hazardous location area;

a user equipment (UE) located in the hazardous location area;

a sensor operatively associated with the enclosure to sense an operating condition of the hazardous location area or the UE;

a controller located in the safe area, and configured to control at least one actuator operatively associated with the enclosure to implement a controlled purge + pressurization process to control an environmental condition of the hazardous location area;

a plurality of input/output (I/O) modules communicating with the controller, the plurality of I/O modules including:

a first I/O module configured to receive a sensor signal from the sensor, and to provide sensor data to the controller;

a second I/O module configured to provide control data or signaling from the controller to the actuator; and

a third I/O module configured to control power to the UE.

2. The system of claim 1, further comprising a user interface controller (UIC) operatively coupled with the controller and configured to allow a user to control the enclosure or to configure the controller.

3. The system of claim 2, wherein the UIC is located proximate the enclosure.

4. The system of claim 1 , wherein the sensor is a pressure sensor to sense a pressure of the interior of the enclosure.

5. The system of claim 1, wherein the sensor is a temperature sensor to sense a temperature of the interior of the enclosure.

6. The system of claim 1, wherein the sensor is a flow sensor to sense an inlet or outlet gas flow rate associated with the interior of the enclosure.

7. The system of claim 1, wherein the sensor is a UE current sensor to sense an inlet or outlet gas flow rate associated with the interior of the enclosure.

8. The system of claim 1, wherein the actuator is a relay to control power applied to the UE.

9. The system of claim 1, wherein the actuator is a vent to control output gas flow from the interior of the enclosure to control the environmental condition of the hazardous location area.

10. The system of claim 1, wherein the actuator is a valve to control input gas flow into the interior of the enclosure to control the environmental condition of the hazardous location area.

11. The system of claim 1, wherein the controller is configured to communicate with a distributed control system (DCS).

12. The system of claim 11, wherein the controller is configured to send the sensor data to the DCS.

13. The system of claim 1, wherein the controller is configured to calculate trending data based on the sensor data received from the sensor.

14. The system of claim 1, wherein the I O modules are configured to exchange data with the controller by one of:

an Ethernet connection;

a Wi-Fi connection; a Bluetooth connection;

an NFC connection; or

an RS-485 connection.

15. A purge + pressurization method, comprising:

using a controller located in a safe area which is physically isolated from a hazardous location area to:

control a first I/O module to receive a sensor signal form a sensor operatively associated with an enclosure comprising a user equipment (UE);

control a second I O module to provide control data to at least one actuator operatively associated with the enclosure to implement a controlled purge + pressurization process to control an environmental condition of the hazardous location area; and

control a third I/O module to control power to the UE.

16. A control system located in a safe area, comprising:

a controller configured to control at least one actuator operatively associated with an enclosure to implement a controlled purge + pressurization process to control an environmental condition of a hazardous location area;

a plurality of input/output (I/O) modules communicating with the controller, the plurality of I/O modules including:

a first I/O module configured to receive a sensor signal from a sensor, and to provide sensor data to the controller;

a second I/O module configured to provide control data from the controller to an actuator; and

a third I/O module configured to control power to a user equipment (UE).

17. The system of claim 16, wherein the controller includes a trending module to analyze trends of the sensor data.

18. The system of claim 16, wherein the controller is configured to communicate with a distributed control system (DCS).

19. A purge + pressurization system, comprising:

an enclosure with an interior defining a hazardous location area, and an exterior defining a safe area which is physically isolated from the hazardous location area;

a user equipment (UE) located in the hazardous location area;

a sensor operatively associated with the enclosure and configured to sense an operating condition of the hazardous location area or the UE;

a main controller located in the safe area, and configured to implement a controlled purge + pressurization process to control an environmental condition of the hazardous location area; a sub-controller located in the hazardous location area, the sub-controller operatively coupled with the main controller and with the sensor to provide sensor data from the sensor to the main controller, and operating under control of the main controller to control at least one actuator operatively associated with the enclosure to implement the controlled purge + pressurization process.

20. The purge + pressurization system of claim 19, further comprising:

a second enclosure with an interior defining a second hazardous location area, the second hazardous location area being physically isolated from both the safe area and the hazardous location area;

a second UE located in the second hazardous location area;

a second sensor operatively associated with the second enclosure to sense a second operating condition of the second hazardous location area or the second UE;

a second sub-controller located in the second hazardous location area, the second sub- controller operatively coupled with the main controller and with the second sensor to provide sensor data from the second sensor to the main controller, and operating under control of the main controller to control a second actuator operatively associated with the second enclosure to implement a second controlled purge + pressurization process to control an environmental condition of the second hazardous location area.