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Markes International Unity 2, User Manual

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Markes International Unity 2 User Manual Download Page 13

 

 

 

QUI-1057

Page 13

Markes International Ltd 

T:

 +44 (0)1443 230935   

F:

 +44 (0)1443 231531   

E:

 [email protected] 

 

www.markes.com 

2.2.2

 

Leak test 

Sam

pl

e

 Tube

Sp

li

t T

ube

C

ol

d

 Tra

p

GC

Heated Valve

Pressure and flow

Pressure (flow optional)

Pressure, no flow

KEY

 

From the Standby position the UNITY 2 Status changes to Leak test. The system allows carrier gas through 
the tube and into the cold trap and split filter and the whole sample flow path is pressurised to capillary 
column head pressure. Carrier gas continues to be supplied to the capillary analytical column throughout 
the leak test (as it is through every other stage of UNITY 2 operation). 

After 5 seconds the flow path is isolated from the capillary column head pressure and a pressure 
transducer monitors the pressure in the sample flow path. If the measured pressure drops by more than 
5% in 30 seconds this is classified as a leak in the sample flow path and UNITY 2 status changes to Tube 
Leaked.   

If the system maintains pressure, no leak is detected and UNITY 2 passes on to the second part of the 
leak test.  The flow path is depressurised briefly.  The sample flow path pressure is again monitored to see 
if it increases by 5% over 30 seconds.  This would indicate an internal leak across the heated valve.  If 
UNITY 2 fails this part of the leak test, the status again changes to Tube Leaked.  Failure of this part of the 
leak test requires the attention of a trained service engineer. 

The main causes of Leak Test Failure are: 

 

Wearing of the O-rings which seal the tube 

 

Interference with the tube seal by fibres and particles 

 

Damaged O-rings  

 

Leaking split filter tube seal 

 

Wearing of the cold trap seals 

 

See the Technical Support Manual for further information. 

Summary of Contents for Unity 2

Page 1: ...Markes International Ltd T 44 0 1443 230935 F 44 0 1443 231531 E enquiries markes com www markes com QUI 1057 Version 2 0 February 2014 User manual UNITY 2 ...

Page 2: ... 1 6 1 Physical properties 8 1 6 2 Electrical properties 8 1 7 Technical support contact details 8 2 Instrument familiarisation 9 2 1 Hardware 10 2 1 1 Sample tubes 10 2 1 2 Tube desorption oven 10 2 1 3 Tube filters and seals 10 2 1 4 The cold trap 10 2 1 5 Cold trap cooling and heating 10 2 1 6 Trap filters and seals 11 2 1 7 Split filters 11 2 2 Sequence of operation 12 2 2 1 Standby 12 2 2 2 L...

Page 3: ...tronic Mass Flow Control 22 3 Software 23 3 1 Running the software 23 3 2 Status bar 23 3 2 1 External ready signal 24 3 3 Toolbar functions 25 3 3 1 Method Linking 27 3 3 2 The Trap Heat Method 29 3 3 3 Schematic display of UNITY 2 status 30 3 3 4 Controlling method 30 3 4 UNITY 2 Options 30 3 4 1 Configuration 31 3 4 2 GC Interface 32 3 4 3 Gas Flow 32 3 4 4 Methods 33 3 4 5 Reporting 35 3 5 UNI...

Page 4: ...ary 48 4 4 Technical support 48 5 Technical Support 49 5 1 Routine maintenance schedule 49 5 2 Sorbent Tubes 49 5 2 1 Packing tubes 49 5 2 2 Lifespan of tubes 50 5 2 3 Conditioning tubes 51 5 2 4 Long term storage of clean and sampled tubes 52 5 2 5 Changing tube seals and filters 52 5 2 6 Changing the charcoal split tube filters 53 5 2 7 Changing DiffLok cap o rings UltrA 53 5 3 Cold Trap 55 5 3 ...

Page 5: ...tended for use in domestic establishments or establishments directly connected to a low voltage power supply network that supplies buildings used for domestic purposes Where equipment is used in a field placement environment care must be taken to ensure that the instrument is not exposed to detrimental conditions i e rain wind or sun Exposure may diminish the performance cause damage to the instru...

Page 6: ...T PART DAMAGE Damage to the instrument or module may occur This damage may not be covered under standard warranties Injury may occur if proper lifting procedures are not followed symbol to alert the user that personal injury or instrument damage may occur if the instrument is improperly used or if instructions are not followed correctly This label indicates the instrument must not be disposed in r...

Page 7: ...of the hydrogen system is carried out in accordance with all applicable codes and standards Markes International will assume no liability for any damage or injury caused by the use of hydrogen For further advice on the use of hydrogen as a carrier gas please contact Markes International Technical Support 1 4 5 Cleaning and decontamination Please consult Markes International or your local agent for...

Page 8: ...e or humidity allow 2 hours for return to the recommended ranges before switching on 1 6 Technical Specifications 1 6 1 Physical properties Height 40 cm 15 75 Width 16 cm 6 3 Length 51 cm 20 Mass 16 kg 35 2 lbs 1 6 2 Electrical properties Maximum Power 650 W Line voltage 100 240 V automatically selected Frequency 50 60 Hz Input inrush current A 40 A cold start 1 7 Technical support contact details...

Page 9: ...QUI 1057 Page 9 Markes International Ltd T 44 0 1443 230935 F 44 0 1443 231531 E enquiries markes com www markes com 2 Instrument familiarisation ...

Page 10: ...ow path contamination in the event that sorbent particles or high boiling sample materials migrate out of the tube The filters are readily accessed for user replacement See Technical Support Manual 2 1 4 The cold trap The quartz cold trap contains a 2 mm diameter x 60 mm long bed of sorbent 30 to 100 mg depending on sorbent density supported by quartz or glass wool Note that the length of the firs...

Page 11: ...be replaced It is recommended that UNITY 2 is professionally serviced once per year and that the valve end seal be changed as part of this annual maintenance operation 2 1 7 Split filters There is a split filter tube packed with charcoal SERUTD 5065 on the split line upstream of the on off solenoid and needle valves This prevents the split portion of the sample from contaminating the valves and fr...

Page 12: ... placed and sealed into the flow path of UNITY 2 for conventional 2 3 stage desorption it undergoes the following sequence of operations standby leak test prepurge primary desorption pre trap fire purge and secondary desorption 2 2 1 Standby Sample Tube Split Tube Cold Trap GC Heated Valve STANDBY Pressure and flow Pressure flow optional Pressure no flow KEY ...

Page 13: ...s the pressure in the sample flow path If the measured pressure drops by more than 5 in 30 seconds this is classified as a leak in the sample flow path and UNITY 2 status changes to Tube Leaked If the system maintains pressure no leak is detected and UNITY 2 passes on to the second part of the leak test The flow path is depressurised briefly The sample flow path pressure is again monitored to see ...

Page 14: ...essure and flow Pressure flow optional Pressure no flow KEY Each tube must be purged thoroughly with carrier gas to remove air before heat is applied Even the smallest trace of oxygen could result in sorbent and possible analyte oxidation generating artifacts and compromising data quality There is also the option in this step to perform an elevated temperature purge See Section 3 6 4 ...

Page 15: ...Pressure and flow Pressure flow optional Pressure no flow KEY At the start of primary tube desorption the tube oven begins to heat either from ambient or from the temperature of the optional elevated temperature purge if selected Note that the tube desorption time is measured from the beginning of tube oven heating and not from the time at which the sample tube reaches the desorption temperature ...

Page 16: ...nd flow Pressure flow optional Pressure no flow KEY Following primary desorption the heated valve is moved and carrier gas is flushed through the split tube and the trap to remove any residual air and water prior to trap injection It may also be used to dry purge the cold trap prior to injection when direct desorbing solid or humid samples This pre trap fire purge time can be adjusted in the TD me...

Page 17: ... flow optional Pressure no flow KEY The final stage is secondary trap desorption The cold trap is heated at a rate of 100 C s during the first seconds ensuring rapid desorption of analytes into the carrier gas stream The flow through the cold trap at this stage is determined by the column flow and any outlet split NOTE the flow path of UNITY 2 remains in the trap desorption configuration until the...

Page 18: ...r it is strongly recommended that the tube extractor tool included in the shipping kit is used to remove the tube Use the tool to grasp the tube at the end released from the tube seal and pull steadily 2 4 Desorb and split flows 2 4 1 Gas flow through the cold trap The UNITY 2 cold trap operates in backflush mode the sample gas stream enters and leaves the cold trap through the narrow bore restric...

Page 19: ...flow path will then alter so that there is no split flow only the desorb Measuring and adjusting flows during Set Gas Flow A flow meter is used to measure the gas flows on UNITY 2 non Electronic Carrier Control ECC A simple er a digital one is more convenient and is available from Markes When UNITY 2 is setup with ECC the flow can be read from the GC However it can be useful to confirm the flow re...

Page 20: ...if used at less than 2 ml min Flow through tube during tube desorption desorb flow split flow if selected Flow through trap during tube desorption desorb flow Flow through trap during trap heat column flow split flow if selected 2 4 7 Sample splitting UNITY 2 may be set up to offer sample splitting between zero splitless and 10 000 1 double split The split that is required for a particular analysi...

Page 21: ...then an overall ideal split can be calculated For example if the expected mass of analyte on the sample tube is 50 µg and the analytical column capacity is 100 ng then a total split of at least 1 500 is required to prevent column overload i e only 0 2 of the sample must be transferred to the column One of three different split modes can be utilised Zero split or splitless Unusually among thermal d...

Page 22: ...at Column Flow Split Flow 2 4 12 UNITY 2 systems with Electronic Carrier Control ECC When installed with certain models of commercial GC MS UNITY 2 systems can be configured with electronic control of the carrier gas as it leaves the cold trap and enters the fused silica or length of analytical capillary column inside the transfer line In this case manual adjustment of the desorb and split flows a...

Page 23: ...tain default parameters when UNITY 2 software is first downloaded If for some reason communication is not established an Instrument not Detected box appears with a number of options Cycle Power and retry Run simulation Select options Exit Choose Select options This will take you to the Ports tab of Options under the View menu see Section 2 4 4 Ensure that the correct PC comms port is selected Chan...

Page 24: ...as indicates whether the dry air or nitrogen is at a high enough pressure for the Peltier coolers to operate If Purge Gas is displayed as Off then this indicates that the purge gas pressure is not high enough In this scenario the Peltier coolers will be switched off NOTE A run may be started when UNITY 2 is Not Ready and the run will then pause waiting for the appropriate zone to reach temperature...

Page 25: ... icon at the top left hand side of the toolbar This brings up the directory nominated under Options see Section 3 4 1 containing UNITY 2 method files Select the required file name and click OK or double click on the required file name to access it Saving a method New methods can be saved by 1 Pressing the floppy disk icon at the left of the tool bar 2 Selecting File Save 3 Pressing CTRL and S 4 Se...

Page 26: ... is printed Copy method parameters Ensure that the UNITY 2 method you wish to copy is the active method Clicking on it with the left hand mouse button will make it active if necessary Select Edit Copy or click the copy icon on the toolbar the shortcut CTRL and C can also be used Copy will put a text copy of the active method onto the Windows Clipboard in English Only thus allowing you to Paste the...

Page 27: ...w sample UNITY 2 schematic This is accessed using the status icon or by selecting View Status Show See Section 3 3 3 Controlling method Used to assign the active method as the controlling method by clicking the icon See Section 3 3 4 Leak test A leak test may be carried out manually via the leak test icon Clicking on this icon opens a dialogue box with a button to pressurise the flow path and to p...

Page 28: ...ct the desired sequence file Delete a highlighted method from the Right click and select the Delete Item option or press the delete key on the keyboard Double click on the existing number and appropriate figure from the drop down method The software allows 1 100 injections of a particular method Checking the recycle box at the top left corner of the method linking table This will recycle the proce...

Page 29: ...ethod The required parameters are entered in the boxes Checking the relevant boxes will activate the split on during trap heat standby Trap Heat is selected either by selecting Instrument and then selecting Trap Heat or by selecting the Trap on the toolbar The following dialogue box then appears Once Trap Heat has been selected UNITY 2 will ask you to confirm that the default method is that which ...

Page 30: ...presentation of the actual status of the instrument One method is identified by UNITY 2 as that controlling the system i e the method dictating the set parameters This method is called the Controlling Method and cannot be deleted or closed until another method is loaded as the controlling method To load another method use either the Load icon or select File and then Load from the menu The loaded m...

Page 31: ...essories are installed U INLET accessory enquiries markes com The configuration page contains the current instrument configuration settings For UNITY 2 operation the Instrument Configuration will be set to UNITY manual The communications port determines serial port number e g Com1 that is used for communicating with Enable Direct Mode If the Enable Direct Mode option is selected an additional mode...

Page 32: ...extended standby In extended standby the Peltier coolers will be switched off When enabled the time out period before which extended standby is entered can be set NOTE The time out period only starts once the instrument has entered standby 3 4 2 GC Interface Used to set the GC Interface logic The GC Interface logic is set to reflect whether the GC sense is Open or Closed for both GC Start Out and ...

Page 33: ...ng the drop down box NOTE Carrier type only needs to be set when using MFCs The carrier gas pressure as measured by the pressure transducer within the UNITY 2 can be displayed in either psi or kPa depending upon preference and is selected here 3 4 4 Methods This is accessed by selecting View Options Methods There are two method functions which can be changed ...

Page 34: ...thod Path If selected then the active window bar will show the text entered in the Method Name section of the properties dialogue box Paths Show Method Name If selected then the active window bar will show the file name of the method in use with or without the full path depending on whether Show Full Path is selected Trap Heat Method UNITY 2 can use one of two sets of parameters when undertaking T...

Page 35: ...TY 2 Method Name Displays the name of the method used Desorb Start Time Displays the time at which tube desorption started Desorb End Time Displays the time at which tube desorption was completed Peak Desorb Temp Displays the maximum temperature the tube oven reached during the analysis Trap Fire Time Displays the time at which the cold trap desorption started and therefore the time at which a GC ...

Page 36: ...ined from that analysis would be invalid Every part of the UNITY 2 flow path including the main valve is tested for leaks during the pressure test the only exception is the point where the transfer line is connected to UNITY 2 For this reason following installation of the transfer line it is recommended that a leak detector is used to detect any leaks at this point in the flow path Many competitiv...

Page 37: ...icated Tube Conditioning Mode so that contaminants from the tube are vented to the charcoal filter and are not passed onto the cold trap Set the split flow to at least 50 ml min preferably 100 ml min to assist efficient conditioning heck the maximum isothermal temperature for the sorbent in use We advise restricting the conditioning temperature to at least 10 C below this sorbent maximum Set the f...

Page 38: ...nge to Low Carrier Pressure and UNITY 2 will become Not Ready This prevents tubes being heated with a low carrier gas supply which could damage the sorbents in the tube 3 6 2 Standard 2 3 stage desorption Standard 2 3 stage desorption is the mode used for most routine thermal desorption work Mode Set to Standard 2 3 stage desorption Split on in Standby Click on the box to enter a check if Split On...

Page 39: ... split is selected to be off during tube desorption all the analytes will be transferred from the tube to the cold trap If an elevated temperature purge is required see Section 2 6 4 then Time 1 and Temp 1 should be set to reflect the required elevated Prepurge time and temperature In this case Time 2 and Temp 2 become the actual analytical tube desorption time and temperature and time values shou...

Page 40: ...bed from the trap and that the trap is again clean and ready to use for the next sample This is typically set to 3 minutes Trap desorption can be carried out split or splitless i e if a split is required during trap desorption a so called outlet split see Section 1 4 check the relevant box If the split is selected to be off during trap desorption all the analytes will be transferred from the trap ...

Page 41: ...rap heater if heating will start to cool down GC Cycle Time The GC Cycle Time GC Run Time GC Cool Down Time Equilibration if appropriate If a GC Cycle Time is entered UNITY 2 will calculate the time at which it can begin the next tube desorption stage such that at the end of that tube desorption and at the time the trap is ready to heat the GC will have just come ready from the previous analysis T...

Page 42: ... out of line The cold trap is user selectable to be in or out of line during the ambient temperature purge It is generally recommended for the cold trap to be off line at this stage to ensure that any water purged from the tube is not re trapped on the cold trap Applications involving the direct desorption of volatile components from materials such as pharmaceuticals plastics etc are an exception ...

Page 43: ...alytes Gas flows during elevated temperature purge are controlled as described in Section 2 6 2 for the ambient temperature purge When using 2 stages of tube desorption remember to place a check in the second split on box if an inlet split is required for the analysis The gas flow through the hot tube during its analytical desorption the flow through the cold trap the so called desorb flow control...

Page 44: ...velopment provides a convenient method validation tool and allows critical samples to be archived when required For further information on split re collection for repeat analysis see TDTS 24 3 6 6 Cold Trap conditioning Before using for sample analysis the cold trap must be cleaned conditioned If the cold trap contains no molecular sieve or carbonised molecular sieve type sorbents trap conditionin...

Page 45: ...ts Trap in line during elevated tube purge Yes No Split on during elevated tube purge Yes No Primary tube desorption stage 2 if optional elevated temp purge employed 35 to 400 C settable in 1 increments for 0 to 999 minutes settable in 0 1 minute increments Split on during primary tube desorption Yes No Cold trap focusing temperature 30 to 50 C settable in 1 increments Cold trap secondary desorpti...

Page 46: ...n In order to ensure that the PC system is correctly purged of all relevant files it is necessary to follow these instructions fully As with any Windows software the correct way to uninstall the software is to use the Add Remove Programs option from the Control Panel Exactly how this is done will depend upon the version of Windows 3 7 1 Windows 7 1 Click on the start button and select control pane...

Page 47: ...rograms and Features 3 Scroll down the list presented and select Markes TD 5 1 0 4 Right click and select Uninstall Change Program and follow the on screen prompts when asked to remove shared files click yes The Markes TD software should now be uninstalled 3 7 3 Windows XP 1 Click on the Start button and select Control Panel 2 In the Control Panel select Add Remove Programs 3 Scroll down the list ...

Page 48: ...ng on Volatiles which is available from Markes International Ltd direct on Email consumables markes com Fax 44 0 1443 231531 For itemised spares please refer to the shipping kit list in Section 5 1 4 3 Applications library Information on thermal desorption applications can be obtained from your Markes International sales office Alternatively contact Markes International Ltd direct on Email enquiri...

Page 49: ... service UNITY 2 ITEMS Frequency Check Oxygen organics trap replace if necessary Weekly Sample tubes repack replace 200 desorptions Change the charcoal filters split tube 3 months Cold trap repack replace 12 months Cold trap seals Only if damaged leak test failing Replace sample tube seals and filters Only if damaged leak test failing UltrA ITEMS Replace DiffLok cap o rings Only if damaged leak te...

Page 50: ...y a second sorbent retaining gauze inserted using a TubeMate C TBMTE or other suitable tool until the gauze sits firmly on top of the sorbent without compressing the packing A gauze retaining spring is then inserted using the TubeMate to hold the gauze in place Tubes should be impedence tested prior to use A range of pre packed sorbent tubes is available from Markes International see relevant Acce...

Page 51: ...ing when freshly packed and when they have been stored for longer than 24 hours for trace level analysis or 7 days for ppm level analysis without being fitted with inch brass storage caps Tubes should be cleaned using the dedicated tube conditioning mode on UNITY or using the TC 20 Multi tube conditioning rig See Application information TDTS 5 TDTS19 for further details ...

Page 52: ...caps to come loose If refrigeration is to be used caps must be retightened a quarter turn once they have reached their storage temperature NOTE A tube should be allowed to warm up and equilibrate properly at ambient temperature before the beginning of sampling If this is not done a significant mass of water from the atmosphere will be retained in the tube via simple condensation NOTE If tubes are ...

Page 53: ...ilters will require changing at routine intervals SERUTD 5065 Split Filter Tube Packed with Charcoal UNITY 2 SERAAA 1600 Split Filter Tube Glass Packed with Charcoal Air Server systems It is suggested that the filters are repacked with conditioned charcoal every three months Charcoal filters are loaded in the same manner as tubes with the grooved end or fritted end of the glass tube facing the bac...

Page 54: ...s UltrA NOTE Before proceeding ensure that UltrA and UNITY 2 are switched off by closing down the software and switching off the main power switch at the back of the instruments The required parts are U COV07 O ring Size 007 pk 10 SERZ 0351 O ring extraction tool SERZ 0285 O ring insertion tool To gain access to the nozzle seals remove the interface tube of the heated interface from UNITY 2 and th...

Page 55: ...ked with care Empty cold traps should be packed from the wider 2 mm bore end using the following procedure enquiries markes com assemblies rotate the oven assembly around its hinge point towards the back of the instrument This allows access to both hot and cold nozzle assemblies Using the suggested tools replace the ring s are correctly Packing conditioning a cold trap packed traps are available f...

Page 56: ...olar and labile compounds Silanised glass wool does not suffer from these limitations but must not be taken above 275 C or breakdown products from the silylating reagent will coat the sample flow path of the desorber reducing recovery of high boiling compounds NOTE A 6 cm length of the wider bore section of the trap tube measured from the point of the bore restriction is subjected to full cooling ...

Page 57: ... a firm hold of the trap pneumatics assembly during these steps if it is allowed to twist it can snap the cold trap 1 Loosen screw by 4 turns Do not remove the screw completely 2 Gently pull the desorb pneumatic assembly towards the front of the instrument being careful to keep it in the horizontal plane Move the assembly clear of the cold trap enquiries markes com Loosen the steel fitting attache...

Page 58: ...P TUBE Most difficult with a cold system can switch the unit back on to warm up before switching off again and reattempting to withdraw the trap Remove the new packed cold trap from its packaging Gently push the trap tube into the cold trap box DO NOT APPLY EXCESSIVE FORCE TO THE QUARTZ COLD TRAP TUBE If in doubt practice with the trap alignment tool supplied in the shipping kit NEVER SWITCH UNITY...

Page 59: ...ly 1 mm from the black plate Keep a firm hold of the trap pneumatics assembly during these steps if it is allowed to twist it can snap the cold trap Bring the pneumatic assembly back and relocate the screw in the slot Push the assembly gently back in the horizontal plane guided by the screw THE CONNECTOR CAN SNAP THE END OF THE QUARTZ COLD TRAP Apply gentle steady pressure to push the trap into th...

Page 60: ...quiries markes com www markes com Gently tighten the steel fitting attached to the cold trap until slight resistance is felt Refit the front cover Turn on the carrier gas compressed gas and instrument power Restart the software Leak test around the cold trap with a helium leak detector ...

Page 61: ...f instrument then lift away to remove Remove the air lines that supply the heated valve by pulling the white tube while pressing the black lip of the connector Remove the split tube and any sample tubes interconnects enquiries markes com Removing replacing a broken cold trap The carrier gas supply and compressed air to instrument itself must Remove the visible end of the cold trap using the Unscre...

Page 62: ...443 231531 E enquiries markes com www markes com Disconnect the thermocouple and heater wire connectors 1 Loosen the 4 screws highlighted 2 Slide the whole assembly back to allow access to the brass connector and hold in position by tightening one of the rear screws 2 1 ...

Page 63: ...trap with an appropriate tool If the brass connector needs to be removed to access the broken trap then replace it before continuing 1 Feed the trap alignment tool through the cold trap box to ensure any broken glass is removed 2 Loosen the screw holding the heated valve assembly in place and slide forwards again 3 Retighten the 4 screws 4 Reattach the thermocouple and heater connectors ...

Page 64: ...ould pass smoothly up to the o ring in the heated valve before further gentle pressure moves the tool another 1 2 mm If the tool does not move smoothly past the point where it enters the brass connector there may be a misalignment problem Loosen the 4 screws again and ensure the assembly is pushed up against the cold trap box Reinstall a new cold trap as shown in Section 4 2 1 2 mm 2 1 ...

Page 65: ...d gently tighten the brass connector 1 8 turn with a 7 16 spanner and check for leaks again Repeat until no leak is detected DO NOT OVERTIGHTEN OR YOU RISK BREAKING THE COLD TRAP AGAIN enquiries markes com carrier gas compressed gas and In the leak test dialog box select SV4 and HV Leak test around the brass connector with a helium ently tighten the brass n with a 7 16 spanner and check for leaks ...

Page 66: ...rap seals and filters The user may change the cold trap O ring seal on the pneumatic assembly if the cold trap has been broken and damaged the seal To change the seal remove the pneumatic assembly taking care not to damage the cold trap see Section 3 2 Loosen the thread on the steel connector and remove the cap Replace the O ring U COV06 ...

Page 67: ...0 1443 230935 F 44 0 1443 231531 E enquiries markes com www markes com 6 Trademarks UNITY 2 ULTRA ULTRA 50 50 Air Server and SecureTD Q are all trademarks of Markes International Ltd UK Windows is a registered trademark of Microsoft Corporation USA ...

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