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ML435 | v23

Page

18

Expo Technologies UK

T: +44 (0) 20 8398 8011

E: [email protected]

Expo Technologies US

T: +1 (440) 247 5314

E:[email protected]

Expo Technologies China

T: +86 532 8906 9858

E: [email protected]

• Remove small cover plate.
• Whilst holding the central adjustment screw in position using the hex key, loosen the retaining nut.
• Adjust the hex key clockwise to increase, or anti-clockwise to reduce the lift off pressure.
• Before testing, retighten the locking nut whilst holding the adjustment screw in place.
• Carry out the commissioning tests to check the correct setting of the relief valve after adjustment.

• The adjustment is sensitive and it is recommended that a 

1

/

4

 turn (maximum) adjustments are applied 

between tests.

Re-calibration of the Pressure Sensors

The brass nozzle on the sensor is sealed into position using Loctite thread sealant. If the thread has seized up, 
remove to a safe area and heat slightly to soften prior to making any adjustment. This prevents potential damage 
to the brass of the nozzle.
• Disconnect pipe work from the sensor, including pipe located below the sensor.
• Remove sensor by unscrewing anti-clockwise.
• The nozzle is located under the sensor.

• The adjustment is sensitive, turn the nozzle in 

1

/

8

 of a turn steps.

• Turn clockwise to reduce the pressure setting and anti-clockwise to increase.
• Replace sensor, screwing clockwise.
• Reconnect all pipe work.

Orifice Plate

Allen Screw and Lock NUT

Removing the small cover plate 
to set the RLV opening pressure 

Summary of Contents for ML384

Page 1: ...llow these instructions Please refer to the standard for principles and definition These instructions apply only to the pressurizing system it is the responsibility of the manufacturer of the pressuri...

Page 2: ......

Page 3: ...rminal Box 11 Section 6 Installation of the System 12 Relief Valve Unit 12 Air Supply Quality 12 Pipe Work 13 Multiple Enclosures 13 Provision and Installation of Alarm Devices 13 Power Supplies and t...

Page 4: ...b 20 C to 55 C T V 12 1462X Ex pxb ia IIC T6 Gb Ex pxb ia IIIC T95 C Db Tamb 20 C to 55 C OV Purge Outlet Valve is pneumatically operated IS Intrinsically Safe Power Alarm terminal box Timing Method E...

Page 5: ...nts signals 1 8 NPT female minimum 6 mm pipe to be used Visual Indicators Alarm Red Pressurized Green System Purging 4 LEDs that flash sequentially to indicate elapsed time black when not purging IS T...

Page 6: ...te intervals up to 99 minutes tolerance 0 3 seconds Default Setting 99 minutes Weight 27 kg 60lb Type RLV104 ss FS Design number D758RLV Bore Purge Outlet Valve 104 mm Relief Valve 75 mm Relief Valve...

Page 7: ...air supply pres sure during the purge process Operation of the System Once the system is installed correctly turn on the air supply Refer to Commissioning section The purge system commences the purge...

Page 8: ...ver be less than the required purge time The system is now operating correctly in leakage compensation mode If the system has not performed as expected check the installation thoroughly and ensure it...

Page 9: ...switching devices may be limited in their gas group The certification documentation supplied with any such devices must be checked to ensure their suitability This system is primarily designed for use...

Page 10: ...entered the enclosure before pressurization Purging is the process of removal contaminated air and replacement with air or inert gas known to be free from flammable gas The duration of this purge proc...

Page 11: ...ower Interlock switch Alarm Trip Purge Time Machinery Start Normal Operation CLAPS Regulator Pressure Intermediate switch contacts open Intermediate sensor sends falling pressure signal Fault Conditio...

Page 12: ...m specified pressure Purge Flow Sensor The Purge Flow Sensor monitors flow through the Purge Outlet Valve At correct purge flow rates above the minimum specified for purging the sensor sends a signal...

Page 13: ...ntially dangerous to energise the pressurized enclosure in an non pressurized condition when it is known that there is potentially explosive gas or dust in the hazardous location Visual Indicators Vis...

Page 14: ...controls the leakage compensation air flow into the enclosure after the purging is complete It either increases or decreases the air flow into the enclosure as appropriate to maintain a stable runnin...

Page 15: ...might affect the calibration of the device In particular the exterior of the spark arrestor should not be painted or blocked in any way Air Supply Quality The MiniPurge system should be connected to...

Page 16: ...above the minimum the Minimum Pressure Sensor re turns a positive pressurized signal causing the alarm indicator on the control unit to change from red to green When the pressure falls below the minim...

Page 17: ...all screws in the terminals are secure In all cases the application and isolation of power must be controlled by the MiniPurge system using the power interlock signal No switches are permitted between...

Page 18: ...e minimum pressure sensing pipe was removed Open the Purge Flow Restrictor Valve very slowly until the Pressure Relief Valve opens Check the opening pressure is within calibration limits This test can...

Page 19: ...check readings on manometer as system will automatically re purge when it reaches minimum pressure 20 While the system re purges return the CLAPS Regulator to the initial setting 21 If minimum pressu...

Page 20: ...ation There are no unauthorised modifications The air supply is uncontaminated The interlocks and alarms function correctly Approval labels are legible and undamaged Adequate spares are carried The ac...

Page 21: ...nsitive and it is recommended that a 1 4 turn maximum adjustments are applied between tests Re calibration of the Pressure Sensors The brass nozzle on the sensor is sealed into position using Loctite...

Page 22: ...designed for ease of fault finding and many of the components fitted are plug in or chassis mounted Check components by substitution only after establishing that such action is necessary Before carryi...

Page 23: ...n the supply pipe Static pressure of 5 barg must be maintained during purge Check air supply pressure at the inlet to the control unit Ensure that the supply pipe bore is suitable for the flow rate Pr...

Page 24: ...as stated on the Customer Test and Inspection Sheet S0015 018 Pressure gauge Air Supply Pressure 0 10 barg S0015 135 Miniature gauge Logic Pressure 0 4 barg ETM IS31 001 IS battery pack for electronic...

Page 25: ...system merely tops up for any enclosure leakage The system provides an initial high flow of purging air that leaves the PE through the Relief Valve After the initial purging has been completed the Co...

Page 26: ...one PE can be protected by a single system If PEs are connected and purged in series e g Daisy Chained the Outlet Orifice must be fitted on the last enclosure with the Purge Inlet to the first enclosu...

Page 27: ...ally by the user by the use of local isolating switch 1 4 2 In accordance with NFPA 496 Expo Mini X Purge systems can have the Action on Pressure Failure normally Alarm and Trip adjusted by the user t...

Page 28: ...ation do not confuse this flow rate with that caused by excessive setting of the LCV Close the LCV slowly observing the manometer or gauge see item 2 1 3 above The PE pressure will start to fall as th...

Page 29: ...quantity The LCV is too far open and the air flow is holding the RLV open continuously Note Some CFHP systems have a deliberate but modest Continuous air flow through the RLV in normal operation do n...

Page 30: ...in the air supply For this reason a dust and water filter should always be fitted But debris can enter from other sources and it is vital therefore that the procedures described in Section 2 is carrie...

Page 31: ...d Is the pipe to the Power Switch airtight The signal to the Power Switch bulkhead has a restrictor that limits the permissible leakage from the pipe e Note the timer setting Reset the timer to the m...

Page 32: ...e com Appendix A Certifications Download the certificates at www expoworldwide com downloads Component Certificate Number Purge System ATEX Certificate SIRA 01ATEX1295X IECEx Certificate IECEx SIR07 0...

Page 33: ...7 6 29 3 32 3 57 2 027256 6 5 9 02 180 5 33529 7 33529 5 1 0 41 0 0 7 5 6 6 67 0 286 1 67 1 66 67 H 81 7 21 2 67 1 66 67 8 77 1 6 67 1 66 67 72 5 1 81 66 67 7 27 5 6 0 7 5 6 6 127 6 UG 1 352 7 21 0 16...

Page 34: ...50 7 6 7 78 725 17 50 7 6 7 9 6312 G 7521 385 7 0 5 6 77 5 3 1 725 50 35 6685 1 725 6 67 0 385 1 0 1 385 28 1 725 81 7 21 2 25 175 16 6 5 8 76 21 0 1 080 3 0 1 385 57 7 21 77 16 225 7521 7 0 5 72 5 1...

Page 35: ...d NOTE LC BOOST system is optional LC BOOST 71 66 72 66 7 1 PP 29 5 1 PP 1 7 8163 72 5 1 6 0 7 5 5 1 67 786 33529 02 1R 7 668 UG 1 352 7 21 0 16 216 1 PP 2 127 6 SR 7HFKQRORJLHV LPLWHG 2 1R 1 6 7 7 86...

Page 36: ...RM 1 8 NPT 1 8 NPT 1 4 6mm I D 1 4 6mm I D 1 NPT PI H CONNECT TO EITHER A OR B 1 2 NPT 1 2 NPT A B 1 25mm I D MINIMUM 1 8 NPT 1 8 NPT 1 8 NPT ELECTRICAL SIGNAL VIA EEx e JUNCTION BOX RECOMMENDED MINIM...

Page 37: ......

Page 38: ...09 110 111 112 113 114 115 116 117 118 BLACK GREY BROWN BLACK GREY BROWN GREY BLACK BLUE BROWN TERMINAL LAYOUT INTERMEDIATE PRESSURE CONTACTS SEE CIRCUIT DIAGRAM ALARM PRESSURISED CONTACTS MOTOR INTER...

Page 39: ......

Page 40: ...N O T S C A L E SR 7HFKQRORJLHV LPLWHG JOB No FINISH TITLE CUSTOMER SHEET No O F PROJECTION D I M E N S I O N S I N m m 81 7 1 20 DRAWING No 1 NRB from Expo Technologies Limited neither are they to b...

Page 41: ...Pressure Equipment Directive 97 23 EC MiniPurge Systems are classified as not higher than category I under Article 9 of this Directive and intended for use in potentially explosive atmospheres Hazard...

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Page 44: ...ologies Ltd Unit 2 The Summit Hanworth Road Sunbury on Thames TW16 5DB UK Tel 44 0 20 8398 8011 Fax 44 0 20 8398 8014 E mail sales expoworldwide com Qingdao Expo M E Technologies Co Ltd 329 Huashan Er...

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