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Gow-Mac 400 Series, Operating Manual

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39

Series 400 / 402 Gas Chromatograph Operating Manual             GOW-MAC Instrument Co.

May 2017, Rev. 7

Chapter 7 - Software

 

NOTE

&

 

Make sure that power is 

not

 applied to any of the 

instrumentation until 

all 

electrical connections have been 

made between 

all

 devices.

The power cords to the instruments must be connected 

only

 

to a line power source with a protective earth ground.

 

Both the recording device and the GC should be connected to 
the same duplex service outlet to prevent ground loops.

The source voltage must be within the specifi cation of each 
device and/or instrument. Check the requirements for each 
device or instrument in their respective manuals. 

 

 

GOW-MAC GCs can be set up many diff erent ways to acquire and control the data produced 
by the GC. These setups can range from being completely manual, to almost fully automated 
with the proper devices. Signal output from the GC is a voltage level ranging from 0-1 volt, or 
0-10 volts. The full description and function of the external cables are discussed earlier in this 
chapter.  When connecting the GC to an integration device, please refer to the manual for that 
device for proper interfacing connections.

 

NOTE

&

 

Check all input and output specifi cations of instruments 
and other devices to be used in order to ensure that the 
connections to the GC are compatible. If there is uncertainty 
please call GOW - MAC's Technical Support Team at (610) 
954-9000 or Fax us at (610) 954-0599.

 

WARNING

!

THE INSTRUMENT CAN BE DAMAGED IF IMPROPER 
CONNECTIONS ARE MADE.

7.1  Set Up
 
 

Unpack and set up the Gas Chromatograph as per the instructions outlined in this Operating 
Manual.

 
 

Using the Operating Manual provided with your software, unpack, install, and confi gure the 
interface device.

Summary of Contents for 400 Series

Page 1: ... 400 402 400 P 402 P Thermal Conductivity Gas Chromatograph Series 400 120 V 50 60 Hz Series 402 230 V 50 60 Hz May 2017 Rev 7 READ INSTRUCTIONS BEFORE OPERATING PO Box 25444 Lehigh Valley PA 18002 5444 U S A Tel 610 954 9000 ...

Page 2: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 2 ...

Page 3: ...t Warning 9 Important Gas Flow Adjustment Note 10 Chapter 1 Safety Precautions 11 Chapter 2 Specifications 13 Chapter 3 Installation 15 Chapter 4 Operation 23 Chapter 5 Microscale Prep 31 Chapter 6 Valves 35 Chapter 7 Software 39 Chapter 8 Experimental Run Through 41 Chapter 9 Maintenance 47 Chapter 10 Replacement Parts 53 Chapter 11 Mechanical Drawings 55 ...

Page 4: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 4 ...

Page 5: ...h may result directly or indirectly from the use of such information This document contains proprietary information which is protected by copyright All rights are reserved No part of the document may be photographed reproduced or translated into another language without the prior written consent of GOW MAC Instrument Co The warranties made by GOW MAC Instrument Co with respect to the product are v...

Page 6: ...ipment whether or not such injury illness or death is claimed to have been caused by resulted from or was in any way connected with the negligence of the party to be indemnified PROPRIETARY INFORMATION Buyer agrees to maintain all proprietary information disclosed by Seller including such proprietary information obtainable upon examination of the Equipment in confidence and to refrain from any discl...

Page 7: ...vered by this warranty 5 Instrument parts which have been repaired or replaced during the warranty period are themselves warranted only for the remaining unexpired portion of the original six month warranty 6 Repairs adjustments and service performed after expiration of the six month warranty period shall be charged to the purchaser at the then current prices for parts labor and transportation 7 T...

Page 8: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 8 ...

Page 9: ...AIL TO PERFORM AS DESIGNED AND PERSONS WHO RELY ON THIS PRODUCT FOR THEIR SAFETY COULD SUSTAIN SEVERE BODILY INJURY OR DEATH The warranties made by GOW MAC Instrument Co with respect to the product are voided if the product is not installed used and serviced in accordance with the instructions in this manual Please protect yourself and your employees by following these operating instructions We en...

Page 10: ...switch and energize the detector current Thirty 30 psig is adequate for most columns 2 Before reading measurement allow five 5 minutes for the rate to equilibrate after each adjustment 3 Inert carrier gas MUST be flowing through both columns A and B as well as sides A B of the TC detector at all times THIS IS EXTREMELY IMPORTANT and NECESSARY to preserve the filaments Failure to set flow rates on both...

Page 11: ...ad the ac outlet with other electrical equipment E Adhere to the color coding descriptions when hooking up electrical connections F Repair or replace faulty or frayed wiring IMMEDIATELY when it occurs 1 3 COMPRESSED GAS CYLINDERS Compressed gas cylinders are potential sources of serious accidents injuries and even death if proper precautions and safety practices are not followed Therefore during h...

Page 12: ...table hand truck J Never tamper with safety devices in valves or cylinders K Do not store full and empty cylinders together Serious suck back can occur when an empty cylinder is attached to a pressurized system L No part of a cylinder should be subjected to a temperature higher than 52 C 125 F Do not permit flame to come in contact with any part of a compressed gas cylinder and pressure relief devi...

Page 13: ...n by Mayo Pike et al in Microscale Organic Laboratory E Wiley Son N Y 1986 Dimensions Overall 16 50 H 410 mm x 12 00 W 300 mm x 11 00 D 270 mm Weight 27 lbs 12 26 kg Power Requirements Series 400 110 120 VAC 50 60 Hz 600 W max 10 A circuit breaker Series 402 220 240 VAC 50 60 Hz 600 W max 4 A circuit breaker Column Oven Dimensions 16 19 cm H x 25 40 cm W x 18 41 cm D Volume 7570 67 cm3 V Temperatu...

Page 14: ...ice Bulletin at ambient temp 120 mA with N2 Detector Power Supply Line operated solid state integrated circuit regulated constant current 55 Vdc max 300 mA max Ripple and noise 5 mV rms Injection Ports Dual injection ports Low Volume Injection Method direct on column or gas sample valve injection Septums standard 9 mm Operating Temperature 0 400 C Temperature Control solid state time proportioning...

Page 15: ...110 130 V 50 60 Hz Series 402 600 W at 220 240 V 50 60 Hz CAUTION Operating instructions for bother series are the same except for line voltage requirements To prevent damage to the instrument make sure that the AC electrical outlet is the correct voltage for your instrument BEFORE plugging it into the outlet E GOW MAC Installation Kit Part No 59 400 or 1 8 o d clean copper tubing and Swagelok fitt...

Page 16: ...l or table Read Chapter 1 Safety Precautions to ensure proper handling of compressed gas cylinders D An electrical outlet ac should be near the location where the GC is to be installed If the outlet is not a 3 pin type make sure that a good ground is available since a good ground is necessary for proper operation The ac outlet should be connected to a circuit that is not heavily loaded with other ...

Page 17: ...he recorder cable to the terminals located at the rear of the GC Figure 3 1 Connection should be made as follows Black to Black Red to Red Silver to Green B Connect the other end of the recorder cable to the proper terminals on the recorder GND Recorder GND Figure 3 1 Series 400 GC and Recorder Connection NOTE While polarity is unimportant because of the Polarity Switch the shielded ground wire sh...

Page 18: ...EQUIREMENTS OF THE COMPRESSED GAS ASSOCIATION CGA A A 1 8 o d stainless steel tube extends from the rear of the GC Figure 3 2 This is the CARRIER GAS INLET B Either using the GOW MAC Installation Kit Part No 59 400 or fittings and clean copper tubing of your own connect a 1 8 o d piece of copper tubing from the gas outlet located on the gas regulator of the gas cylinder to the CARRIER GAS INLET on ...

Page 19: ...w to 30 mL min through BOTH columns A and B which flows through BOTH sides of the detector Perform the following leak check procedure 1 Open the hinged column oven cover 2 Check all column connections 4 for tightness The columns supplied are 1 4 o d and the nuts 4 require a 9 16 open end wrench 3 Check septum nuts on front panel for tightness finger tight 4 Check the carrier gas connections at the b...

Page 20: ...ng for bubbles may be used Refer to Figure 3 3 to locate possible leak areas NOTE STEPS 7 8 9 MAY BE OMITTED IF A GOW MAC GAS LEAK DETECTOR IS AVAILABLE Column A Column B Metering Valves for Columns A B Pressure Reduction Valve Pressure Switch Detector H e l I u m Carrier Gas Injection Port for Column A Injection Port for Column B Figure 3 3 IMPORTANT LEAK CHECKS SHOULD BE RUN PERIODICALLY AND ARE...

Page 21: ...nded for the flow measurement Proceed as follows A Gently squeeze the reservoir of the flowmeter until a stream of soap bubbles emerge Allow the soap bubbles to rise and wet the sides of the glass meter START the stop watch when a soap bubble reaches the 0 mark on the meter STOP the stopwatch when the soap bubble reaches the 10 mark on the meter The elapsed time in seconds for the soap bubble to ris...

Page 22: ...d frequency _____ Interconnecting cables to additional instruments installed _____ Power OFF B Pneumatic _____ Required gas supplies hooked up _____ Carrier gas flowing through BOTH columns and detector _____ Cylinders chained or strapped to wall or bench _____ Regulators set for suggested delivery pressure 20 30 psig _____ Connecting lines and fittings leak checked _____ Flow rates checked and adju...

Page 23: ...ntinuing Refer to Figure 4 1 14 15 1 2 3 4 5 6 7 8 9 10 11 12 13 GAS CHROMATOGRAPH Series 400 GC 16 17 Figure 4 1 Front Panel Controls 1 Injection Port A 10 Detector Current Switch 2 Flow Adjustment A 11 Zero Control 3 Column Temp Control 12 Attenuator 4 Detector Temp Control 13 Bridge Current Control 5 Injection Port Temp Control 14 Flow Adjustment B 6 Digital Panel Meter 15 Injection Port B 7 Se...

Page 24: ... function chosen by the SELECTOR BUTTONS 7 SELECTOR BUTTONS a INJECTION PORT TEMPERATURE C selects injection port temperature to appear on the DIGITAL PANEL METER b COLUMN OVEN TEMPERATURE C selects column temperature reading to appear on the DIGITAL PANEL METER c DETECTOR TEMPERATURE C selects detector temperature reading to appear on the DIGITAL PANEL METER d DETECTOR CURRENT selects detector cu...

Page 25: ...atures are recommended Recommended starting bridge setting is 100 mA for helium carrier gas 14 FLOW ADJUSTMENT B 15 INJECTION PORT B 16 COLUMN OVEN LID 17 EXIT PORTS A B 18 COLUMNS The oven is designed to accept twelve 12 feet of 1 4 tubing Correspondingly longer lengths of 1 8 tubing can be wound on a mandrel of 4 o d Columns of 1 8 o d with 1 4 ends can be ordered from GOW MAC Figure 4 2 illustr...

Page 26: ...in for 1 8 columns 60 mL min for 1 4 columns 4 Check for leaks as described in Chapter 3 5 Disconnect flowmeter 6 Allow 5 minutes to purge the system before turning power ON B Temperature Controls NOTE TEMPERATURE CONTROL KNOBS are locking type Push locking ring IN to turn knob 1 ALL switches should be in the OFF position 2 Turn DETECTOR CURRENT CONTROL fully counterclockwise CCW THIS STEP IS EXTRE...

Page 27: ...Line Find your carrier gas and do not go above the line when setting mA and temperature 7 After 20 30 minutes press the SELECTOR BUTTON for BRIDGE CURRENT 8 Turn the DETECTOR CURRENT SWITCH to ON 9 Adjust the BRIDGE CURRENT CONTROL to the desired setting refer to CHART 4 1 NOTE IF BRIDGE CURRENT DOES NOT RESPOND CHECK CARRIER GAS PRESSURE THE FILAMENT PROTECTOR SWITCH MUST HAVE 15 20 PSIG TO OPERA...

Page 28: ...ntinues after 5 to 6 hours check for leaks in the system G Refer to the recorder manual for correct chart speeds warm up times etc 4 4 Computer Integrator Zeroing The Series 400 GC may also be used with commercially available computing integrators After the integrator is properly connected to the instrument it may be turned ON At this time the electrical or recorder zero should be established and ...

Page 29: ...umption FLOW RATE MUST NOT FALL BELOW 20 psig 4 8 Shutdown Procedure The following sequence of steps should be followed in the given sequence to insure proper cool down of your GC and longer life of the detector filaments A Push the SET and DETECTOR CURRENT Buttons IN B Turn the DETECTOR CURRENT CONTROL counterclockwise until the DIGITAL PANEL METER displays between 28 to 40 Then turn the CURRENT S...

Page 30: ...ems at the beginning of each day or shift and when starting up the GC after a weekend shutdown A Electrical _____ Additional instrumentation is connect properly B Pneumatic _____ Gas cylinder pressure is sufficient _____ Cylinder pressure regulator set properly _____ Gas flow rates are adjusted properly _____ Appropriate columns are installed _____ Leak check C Front Panel _____ All temperature setti...

Page 31: ...etector with threaded heated exit ports Preparative columns included when P N 59 425 is ordered consist of one each of a 8 x 1 4 20 Carbowax 20M on Chrom P 80 100 mesh and b 8 x 1 4 DC 710 on Chrom P 80 100 mesh B Temperature Control 1 The temperature of the heated exit ports is achieved with a separate control unit mounted on the rear of the GC Fig 5 1 Included in the temperature control unit are...

Page 32: ...of the exit port read on the Panel Meter 0 50 100 150 200 250 0 10 20 30 40 50 60 70 80 Dial Settings Temperature C Chart 5 1 Exit Port Temperature Settings Graph represents average dial and temperature settings Your readings will vary We suggust plotting your own instrument s curve on the above curve for easy and accurate reference Allow three hours between dial setting changes for temperature to...

Page 33: ...o practice rotating the collection tube GENTLY to obtain just enough pressure to make a good seal but not enough to unseat the joint 4 The preparative GC fraction is now collected as it passes through the exit port into the collection tube Efficient collection is facilitated diminished aerosol formation by the large heat sink afforded by the mass of the stainless steel adapter Once the recorder indic...

Page 34: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 34 ...

Page 35: ...VE AN UPPER TEMPERATURE OF 175 C OR 300 C DO NOT EXCEED THESE TEMPERATURES UPPER TEMPERATURE LIMITS VALCO LOW TEMPERATURE VALVES 175 C VALCO HIGH TEMPERATURE VALVES 300 C 6 2 Valves and Their Functions Valves are used to accomplish two basic operations in gas chromatography One is inject a sample onto the head of the GC column and the other to reroute or switch the flow of the carrier gas or sample...

Page 36: ...ple source or the sample may be passed through by means of a pump or other sample container The size of the sample loop is fixed but can be easily changed see below The valve is first placed in the counter clockwise CCW position that is the valve handle is as far counter clockwise as it will go At this time the sample is purged through the loop and the carrier gas merely passes through the valve to ...

Page 37: ...ur s may vary Refer to enclosed flow diagram A Pneumatically actuated gas sample valves require compressed air gas that is free of oil and water to function An air pressure of 30 50 psi is recommended to fully drive the valves B A TTL Interface PCB enables the operator to control the pneumatic actuated valves that are installed in the GC via an external controller i e computing software or computin...

Page 38: ...eries 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 38 A B Green Brown Yellow Black 1 2 3 4 D Refer to the External Control Option in the software operating manual for complete installation operating instructions ...

Page 39: ...tups can range from being completely manual to almost fully automated with the proper devices Signal output from the GC is a voltage level ranging from 0 1 volt or 0 10 volts The full description and function of the external cables are discussed earlier in this chapter When connecting the GC to an integration device please refer to the manual for that device for proper interfacing connections NOTE...

Page 40: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 40 ...

Page 41: ...rb P AW DMCS 80 100 mesh NOTE If other columns are to be used corresponding column and injection port operating temperatures should be determined 8 3 Gas Flow IMPORTANT Inert carrier gas MUST be flowing through both columns A and B as well as sides A B of the TC detector THIS IS EXTREMELY IMPORTANT and NECESSARY to preserve the filaments Failure to set flow rates on both sides causes oxidation and de...

Page 42: ...R CURRENT SWITCH to ON J Adjust the CURRENT CONTROL to 100 mA K Turn the recorder ON L Zero the recorder Chapter 4 If a peak goes off scale the ATTENUATOR should be turned to a position that brings the peak back on scale M Set POLARITY SWITCH for an upscale drift 8 5 Procedure A Temperatures required for this experiment are 130 C on the DETECTOR and 120 C on the COLUMNS The INJECTION PORT TEMPERATU...

Page 43: ...ell as the other pertinent information about this sample The first small peak to be eluted is the air peak and it will be followed by the 4 components of the mixture in the order listed in Table 8 1 You can verify the identity of each peak by running small samples of each liquid individually Note the reproducibility of the retention times A typical chromatogram is shown in Figure 8 1 Figure 8 1 Typ...

Page 44: ...general rule is that polar columns retain polar samples and vise versa Note that this is true and in this example where the polar polyglycol Carbowax retained the alcohol until last and the non polar silicone oil DC 200 retained the non polar paraffin until last This partitioning of the sample between liquid and gas phases is much more important than the boiling points of the components The latter a...

Page 45: ...aments A Push the SET and DETECTOR CURRENT Buttons IN B Turn the DETECTOR CURRENT CONTROL counterclockwise until the DIGITAL PANEL METER displays between 28 to 40 Then turn the CURRENT SWITCH to off position C Repeat Steps A B above for the COLUMN DETECTOR and INJECTOR D Let the GC cool down for 30 minutes For quicker oven cool down the column oven lid may be lifted and left open E Let the GC cool ...

Page 46: ...Operating Manual May 2017 Rev 7 46 CAUTION IT IS MOST IMPORTANT THAT ELECTRICAL POWER BE TURNED OFF BEFORE THE HELIUM IS TURNED OFF AS LONG AS THE CELL AND FILAMENTS ARE HOT THE HELIUM SHOULD BE FLOWING THOUGH THE FLOW RATE CAN BE REDUCED TO CONSERVE HELIUM ...

Page 47: ...eposited on the filaments or cavity walls of the TC cell Such deposits will affect the heat transfer properties of the cell and change the zero balance progressively until the zero will no longer be sufficient Contamination of the detector may be removed by the following method AFTER THE OVEN HAS COOLED COMPLETELY 1 Shut OFF carrier gas and electrical power to the GC 2 Remove columns from the instrume...

Page 48: ...he left side of the instrument C Remove the septum nuts injection port nuts D Remove all screws from the front panel E Remove two 2 screws from the back panel F Remove the insulation to uncover the detector cell housing the detector bracket and the exit tubes CAUTION INSULATION CONTAINS FIBERGLASS THE USE OF GLOVES AND FACE PROTECTION IS STRONGLY RECOMMENDED G Disconnect the CELL LEADS from the bo...

Page 49: ...SOLVENTS PROPERLY E Refer to the GENERAL SERVICE BULLETIN following the mechanical drawings of this manual for recommendations on installing new filaments F The new filaments should be installed in the cell the nuts replaced and tightened and a leak check made before the cable is threaded back through the hole in the heater plate 9 4 Columns NOTE When ordering new columns please specify 1 Instrument...

Page 50: ...e septum replaced The INJECTION PORT NUT acts as a heat sink and should be kept clean and polished WARNING INJECTION PORTS MAY BE HOT WEAR APPROPRIATE PROTECTIVE GLOVES 9 7 Temperature Control The Series 400 GC can be operated at temperatures ranging from ambient to 400 C Operating temperature is maintained at the injection ports the column oven and the detector Temperature controls on the injecti...

Page 51: ...e Even with the heaters turned OFF the detector will rise in temperature to about 70 C due to the heat being dissipated by the filaments 9 10 Injector Temperature Control The injection ports are heated by 60 W heaters mounted inside the injector block The temperature control sensor is also located in the block The injection port temperature is controlled in the same manner as the column oven 9 11 P...

Page 52: ...o download the form Once we receive a completed Health Safety form an RMA number will be assigned and further information will be e mailed to you so that you can to send the instrument or TCD back to us Instruments or TCDs received without a completed Health Safety form or RMA will not be permitted into our facility Display the RMA number on your shipping label to insure prompt attention upon arri...

Page 53: ...rrent Power Supply 123 191 230 230 V Temperature Controller 123 177 230 PCB Assembly Display 123 194 Controller Solid State Outlet 124 202 Mechanical Injection Port Assembly 069 30 Assemblies Detector Assembly complete standard 069 78 S Detector Assembly complete preparative 069 78 P Electronic Parts Potentiometer 20K zero 111 178 Controls Switch pressure 120 130 Switch DP2T w Actuator Polarity 12...

Page 54: ... leads 124 175 T Injection Port Nut 176 125 Metering Valve 180 789 Binding Post red 129 172 Binding Post black 129 173 Binding Post green 129 174 Foot rubber 141 452 Septums 9 mm 100 pkg 180 123S Microscale Prep Kit 59 425 2 prep columns GC glassware Microscale Prep Glassware 180 350 Replacement Kit Replacement parts for instruments with preparative option ...

Page 55: ...hapter 11 Mechanical Drawings Thermal Conductivity Detector Assembly Drawing B 18751 Flow Diagram Typical Drawing A 17065 Wiring Schematic 115 V Drawing C 18002 Wiring Schematic 230 V Drawing C 20462 Wiring Schematic 400 P 115 V Drawing C 18002 1 Wiring Schematic 402 P 230 V Drawing C 20462 1 ...

Page 56: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 56 ...

Page 57: ... WIRE COLOR GREEN 4 6 5 BLUE BLACK 3 RED CHART FOR LEADS 5 3 6 4 CELL ASSEMBLY FOR 69 350 400 SERIES B 18751 2 SML 4 23 99 1 1 B18751R2 DWG 1 5 17 01 REMOVED THREADED OUTLET SML R 534 2 6 3 02 UPDATED 125 TUBING PART NUMBER SML FINISH MATERIAL DO NOT NAME SCALE REV NO CHANGE NO DATE BY ANGULAR 1 ECO FILE DWN SCALE DATE CHK TOL UNLESS HOLES 003 NOTED XXX 010 XX 02 X 04 INSTRUMENT CO 277 BRODHEAD RO...

Page 58: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 58 ...

Page 59: ...ETERING COLUMN B COLUMN A DET VALVE B METERING VALVE A CARRIER IN FLOW DIAGRAM 69 400 TCD A 17065 0 SML 8 2 96 N T S A17065 DWG R FINISH MATERIAL DO NOT NAME SCALE REV NO CHANGE NO DATE BY ANGULAR 1 ECO FILE DWN SCALE DATE CHK TOL UNLESS HOLES 003 NOTED XXX 010 XX 02 X 04 INSTRUMENT CO 277 BRODHEAD ROAD BETHLEHEM PA 18017 8600 DWG ...

Page 60: ...GOW MAC Instrument Co 60 ...

Page 61: ...COND RIBBON CABLE GRN WH RED RED BLK RED BLK RED BLK WH GRN WH BLUE BLK BLK BLK COLUMN DETECTOR INJECTOR BLK RED BLUE BLK BLK BLK RED GREEN RED J1 1 2 3 4 RED RED SHIELD B CHANGE THE ZERO 2K RESISTOR TO A 100 RESISTOR P N 110 130 A CHANGE THE ZERO 20K POT TO A 1K POT P N 111 175 1 FOR APPLICATIONS WITH LOW CURRENT OR TCD WITH Ni FILAMENTS NOTES NOTE 1 NOTE 1 POLARITY P N 128 274 METER CHART DESCRI...

Page 62: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 62 ...

Page 63: ...___________________________ If any of the above boxes are checked the following statements and or questions must be answered 1 Specifically describe where on or in the instrument device part there could be any residual contamination for example blood spill on the surface ____________________________________________________________________________________________ ___________________________________...

Page 64: ...GOW MAC Instrument Co Series 400 402 Gas Chromatograph Operating Manual May 2017 Rev 7 64 ...

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