Frequently Asked Questions
FAQ
These FAQs are meant to help you getting the grip of our Hyper-Fast GC instrument, from basic information and tips to assistance in estimating the severity of issues and dealing with minor issues yourself. However, they are general advise only that might not suit your specific issues and circumstances. While we do our best to keep the risks associated with following these tips at a minimum, you follow our tips on your own responsibility. If in doubt, please contact us via service@hyperchrom.com and arrange a thorough examination by our experts. HyperChrom assumes no liability for any harms or damages resulting from information and tips provided within this FAQ.
General
What is the HyperChrom GC?
The HyperChrom GC is a Hyper-Fast Gas Chromatograph that was developed under the lead of Dr. Peter Boeker. In short, this device can do high-speed GC measurements with a resolution comparable to conventional GC. By doing the same analyses up to 50 times faster, your lab could work more efficient than ever before!
What does “GC in seconds” mean?
With HyperChrom, it is possible to transform conventional GC analyses that happen on the scale of minutes (e.g. typically 10 to 60 minutes) into analyses in the scale of seconds (e.g. typically 30 to 120 seconds).
What are the advantages of HyperChrom GC compared to conventional GC?
The measuring times and also the cycle times can be drastically reduced, depending on the application by up to a factor of 50. By using the stainless-steel capillary as a column oven, heating rates of up to 3000 °C/min can be achieved. In addition, the column is cooled down to the initial temperature very quickly after the end of the measurement by means of the fan and the water-cooling system in the tower. This also greatly reduces cycle times. The HyperChrom GC not only has enormous advantages for routine analysis but is also more ecologically sustainable: energy consumption is reduced due to the low thermal mass - an effect that is further increased via the shortened run time per run. In addition, the same separation columns and materials can be used that are used in conventional GC.
Who benefits from the high speed?
For users with high throughput in routine analysis, the HyperChrom GC is of great advantage. In addition, the hyper-fast measurements can provide rapid feedback to the client, which plays a key role in, for example, inspections of incoming goods or process monitoring. Both method development and various research and development problems also benefit from quick results.
What is the average run time and cycle time?
This strongly depends on the application. With our particularly fast cooldown that takes approx. 10 seconds from 350 °C to 40 °C, not only the runtime, but also the cycle time is drastically reduced! For some particularly fast applications, e.g. with a measuring time (or runtime) of 30 seconds, the whole cycle time (measured between the start time of two subsequent samples) is below 1 minute. Most applications are performed with run and cycle times of approx. 1 – 4 minutes. Some example applications running at our clients' labs are separation of over 60 VOCs within 200 seconds, Simulated Distillation (SimDis) separating all n-alkanes from C8 to C40 within 60 seconds or PAH+PCB measurements in a single run within 240 seconds. Further examples can be found here.
Can I simply replace my conventional GC with a HyperChrom GC?
Yes - and no. On the one hand, the HyperChrom GC can be integrated into your measurement chain just like a conventional GC, provided the compatibility of the peripherals is given. On the other hand, the HyperChrom GC is a next generation instrument that delivers outstanding performance. Therefore, it is necessary to deal precisely with the requirements of this instrument and to implement them on site, for example with regard to maintenance and peripherals. We will be happy to help you with this in our training courses offered specifically for this purpose.
How can I be sure that this concept really works?
While the instrument itself is comparably young, there are already renowned and independent peers acknowledging the huge potential of HyperChrom GCs, including Pat Sandra 1, Jan Blomberg from Shell Global Solutions International 2 and the Jury of The Analytical Scientist Innovation Awards 3 who awarded HyperChrom with the 1st place and described the instrument as a gamechanger, allowing clients „to do something that has been speculated about for decades; in short, GC can become much faster, more sensitive and more selective“.
1) Sandra, P. (2015): Go with the Flow (Field). The Analytical Scientist 1115, 32–33. https://theanalyticalscientist.com/techniques-tools/landmark-literature-2015-part3
2) Blomberg, J.; Oldfield, R. (2022): Thermal gradient GC: Opportunities in combining Discrimination-Free Sample-Introduction with Ultra-fast Chromatography. HTC-17 (Hrsg.): 17th International Symposium on Hyphenated Techniques in Chromatography and Separation Technology (May 18–29, 2022 – Ghent, Belgium)
3) The Analytical Scientist Innovation Awards (2018): Strokes of Genius. The Analytical Scientist. December 13th, 2018. https://theanalyticalscientist.com/techniques-tools/tasias-2018-strokes-of-genius
1) Sandra, P. (2015): Go with the Flow (Field). The Analytical Scientist 1115, 32–33. https://theanalyticalscientist.com/techniques-tools/landmark-literature-2015-part3
2) Blomberg, J.; Oldfield, R. (2022): Thermal gradient GC: Opportunities in combining Discrimination-Free Sample-Introduction with Ultra-fast Chromatography. HTC-17 (Hrsg.): 17th International Symposium on Hyphenated Techniques in Chromatography and Separation Technology (May 18–29, 2022 – Ghent, Belgium)
3) The Analytical Scientist Innovation Awards (2018): Strokes of Genius. The Analytical Scientist. December 13th, 2018. https://theanalyticalscientist.com/techniques-tools/tasias-2018-strokes-of-genius
I'm not sure this will work with my particular samples. Can you help me?
Generally, the HyperChrom GC can do most applications that work on conventional GC as well – of course, while increasing the measurement speed up to a factor of 50. The achieved resolution is comparable to the one obtained via conventional GC, equipped with a 20 m separation column with an inner diameter of 0,25 mm. To help you estimating the potential for your company, we provide some example chromatograms for different applications right here on our website. If you are unsure whether or not your samples could work on our system as well, we are happy to estimate or test your samples with the HyperChrom GC. Please contact us via info@hyperchrom.com to discuss the opportunities.
Peripherals, Compatibility and Practical Considerations
How big is a HyperChrom GC?
The HyperChrom GC itself is approximately 70 cm high, 75 cm wide and 70 cm in depth. Like with any other GC, you'll need more space in most cases, if the HyperChrom GC is coupled with peripherals like samplers, detectors (e.g. MS) and chillers.
I'm experienced in conventional GC. Will that help me with working with a HyperChrom GC?
Of course! HyperChrom is based on conventional GC, thus keeping most of its rules. Consider it a next generation GC: While there surely are improvements and changes, everything you know from conventional GC is still the base of Hyper-Fast GC as well. In our experience, users can easily adapt to the HyperChrom concept. Of course, we'll be by your side offering specialised trainings and advise.
Which gases are used?
The HyperChrom GC is compatible with all common carrier gases: helium, nitrogen and hydrogen. If in use with FID, Air can be used as well. For all gases, we recommend an inlet pressure between 5 to 9 bar. The pressure should not exceed 10 bar.
Can autosamplers be used? What range of injection techniques are available?
Of course! HyperChrom GCs are generally compatible with any autosamplers that can work in standalone mode. We recommend to use PAL or XYZ samplers, obtainable e.g. from Agilent, CTC, Gerstel or Axel Semrau. Those samplers can work in standalone mode (meaning they do not rely on a parent GC of the same manufacturer to work) and are compatible with HyperChrom's standard Split/Splitless injector, but also offer increased functionality like e.g. Headspace sampling or SPME. Please contact us via info@hyperchrom.com if you want to talk to us about a specific sampler connection or need a recommendation.
I use a special injection or detection technology. Is the HyperChrom GC compatible?
HyperChrom is committed to providing a suitable solution for specialized requests as well. Please contact us at info@hyperchrom.com, we will be happy to discuss your needs.
Which detectors can I use?
The HyperChrom GC is compatible with different types of mass spectrometers, including both time-of-flight instruments and quadrupole-based systems (both Q-MS and QqQ-MS), provided they can work in standalone mode (i.e. not relying on a parent GC from the same manufacturer). We also offer an FID option tailored to our instrument specifically. The selection of the appropriate detector depends on the application; for example, due to the narrow peak widths generated in HyperChrom GC, Single Quad instruments are not recommended for screening methods. HyperChrom GCs are compatible with systems from different manufacturers, including (but not limited to) Agilent and Markes. For questions about compatibility with specific systems, please contact info@hyperchrom.com.
Which software is used to control a HyperChrom GC?
HyperChrom GCs can be controlled via different ways. We are constantly extending the range of supported software. Currently, we offer a HyperChrom driver for Agilent OpenLab CDS. Alternatively, our standalone software can be used as well. You also can define a method on the instrument itself, using the software of your detector only.
Do I need special consumables?
We specifically designed the instrument to be compatible to the consumables you already know and use. This applies e.g. to the injector with septa, O-rings and liners, but also to ferrules and even to columns!
What type of columns can be used?
You can use (nearly) all analytical capillary columns, limited only by the inner diameter of the stainless-steel heating capillary. Thus, all common separation columns with inner diameters up to 0.32 mm can be used. Typically, we recommend columns with an inner diameter between 0.1 and 0.25 mm, depending on the application and detector. You are free to work with the manufacturer and column type of your choice!
What is the maximum column length?
The length of the separation column in the heating capillary is fixed to 2 or 4 m (depending on the tower installed). Depending on whether the column is using the purged column connectors, the full length of the installed column is increased by approx. 0.5 m. In practice, you could use cut pieces from standard columns produced for conventional GC.
How is the column installed?
Installation of columns is more or less the same effort than it is with conventional GC. In contrast to conventional GC, the column needs to be inserted into the stainless steel capillary. Start at the upper column inlet (injector side) and carefully push the column into the capillary. This can be even easier and quicker when you use the supplied ultrasonic device to reduce friction. The column ends are connected to the injector and detector using graphite ferrules and nuts, as in conventional GC. If you wish to change column types before or after the separation helix, e.g. for a guard column or an uncoated transfer line, you can do so by using our optional, but included purged connectors while keeping the resolution.
If you would like to know more about the installation of the column, or if any questions remain unanswered, please feel free to refer to the manual where column installation is explained in step by step instructions. We also offer training courses where column installation is explained and carried out. Of course, we are also ready to help with any issues or questions via info@hyperchrom.com.
If you would like to know more about the installation of the column, or if any questions remain unanswered, please feel free to refer to the manual where column installation is explained in step by step instructions. We also offer training courses where column installation is explained and carried out. Of course, we are also ready to help with any issues or questions via info@hyperchrom.com.
So you use metal separation columns?
No, this is a common misconception. The HyperChrom GC does not work with separation columns made of metal, but with standard separation columns from fused silica. The „metal column“ you might have seen on our instruments, helically wrapped around the center part, is a stainless steel capillary used for heating only. This capillary is heated resistively and contains the actual separation column – just like a sleeve.
Can I work in Constant Pressure or Contant Flow mode?
Yes, the HyperChrom GC can do both constant pressure and constant flow. This is achieved by programming the pressure using our calculation tool that we provide with instrument delivery. If you need help with the calculation tool, have a look at the detailled manual for the calculation tool or contact us via info@hyperchrom.com.
How long are typical instrument delivery times?
We manufacture in batches with regional partners and then match the devices individually to the specific customer order. Depending also on the configuration ordered, delivery times may occasionally fluctuate. The average time from initial contact to installation is 6-8 weeks.
What happens until installation of my HyperChrom GC?
After your order, we will contact you to arrange an installation date. We will also set a date for training, showing you everything you need to know to start working with your new instrument and to conduct easy maintenance. One of our field service engineers will then install your device at your company. For this, they need the connections that are also common for a conventional GC, e.g. electricity and all gases to be used. We will of course provide you with details on request and prior to installation.
How do I deal with technical difficulties?
Please have a look at this FAQ, particularly at the Troubleshooting chapter. Possibly, your problem is already addressed here. If you have any further questions or need our on-site support, please contact us via info@hyperchrom.com. On our webpage https://hyperchrom.com/service/ you will also find information about our service contracts, which might be interesting for you if you want to get the best possible support.
The Technical Principle
How big is a HyperChrom GC?
The HyperChrom GC itself is approximately 70 cm high, 75 cm wide and 70 cm in depth. Like with any other GC, you'll need more space in most cases, if the HyperChrom GC is coupled with peripherals like samplers, detectors (e.g. MS) and chillers.
Why is the system so open? Where is the GC oven?
The HyperChrom GC uses another principle to heat the separating part of the column than the conventional GC does. By using a stainless steel capillary that is heated resistively, we can generate the heat reproductively and much closer to the actual GC column. That way, we get rid of the air bath oven and its drawbacks, like a high inertia and the need to create a more or less closed-off system.
What is the heating capillary and why does it help to create such fast methods?
The heating capillary houses the separation column. It is wrapped around the central helix tower and is heated resistively. The temperature of the heating capillary is controlled by contactless IR sensors and is constantly adapted to the temperature that is defined within the method. Because of the setup of the heating capillary compared to a conventional GC oven, generated heat is transferred to the separation column much faster and more precisely, allowing exact and reproducible temperature programmes in a much faster way than a conventional GC can.
What is a spatial temperature gradient and what are its benefits?
By using the gradient fan, a negative temperature gradient can be generated from the beginning to the end of the column (mind that this is not taking temperature development over runtime into account). This means that the substances elute from the warmer column area to the colder one during the measurement. Due to that, the substance bands are shifted together and thus focused, because the diffusion on the column is counteracted. In addition, the elution temperature of the analytes is lower due to the onset of the gradient which is very beneficial for thermal sensitive compounds. These effects combined result in a remarkable improvement of resolution.
What is the difference between a gradient and a temperature programme?
The gradient refers to the spatial negative thermal gradient, meaning that at one specific point in time, you would see the temperature decreasing from the top of the helix to the bottom. The temperature programme however refers to the temperature rising over time, comparable to what you know from conventional GC. The gradient is spatial, meaning that it changes temperature over the position of the column only. The temperature programme in contrast is temporal, meaning that it changes temperature over time. The combination of those two dimensions leads to very rewarding chromatographic effects, increasing the resolution to a level enabling a true Hyper-Fast GC.
How is the spatial gradient created?
Both the heating capillary and the separation column lying within are helically embedded in the so-called helix tower, a cylindrical, 3D-printed structure made from aluminum. The heating capillary is resistively heated, creating a constant temperature over the whole capillary. Additionally, the heating capillary is situated in flow channels, allowing air from within the helix tower to flow over the heating capillary. This air flow is much stronger on the bottom of the helix tower (where the detector-side end of the heating capillary is situated) than at the top of the helix tower (where the injector-side is). This air flow is created by the so-called gradient fan, creating an air flow beginning in the bottom of the helix tower. Using a flow resistance within the helix tower, we reduce the air flow the higher it gets. That way, the heating capillary is cooled down again by the air flowing around it. This cooling effect is stronger at the detector side, creating a spatial gradient. [BILD EINFÜGEN]
Why is it useful to cool the helix tower?
The helix tower is used to hold the heating capillary in a way that is needed to create the spatial gradient. It has a great impact on the surroundings of the heating capillary. Having a cooled structure means having a stable structure that is helping to get any spare heat out of the system quickly. Also, the air blown over the heating capillary to create the gradient and to cool down the capillary after measurement is conditioned as well, making the cooldown even faster. Also, measurements are becoming more robust and reproducible. By the way: When using one of our recirculating chillers, you don't even need a source of water nearby!
What is a transfer oven?
The transfer ovens are two ovens that allow the column to change orientation – from a vertical orientation, e.g. coming from the injector or going to a FID, to a horizontal orientation, e.g. from and to the helix tower or an MS. This way, we gain a high flexibility to e.g. include specialised detectors or sampling techniques. Our transfer ovens are built similar to a conventional GC air bath oven. However, opposed to conventional GC, those ovens are used for static temperature zones only, not for conducting an oven programme. For this, we use the much faster and much more precise technique of the heating capillary.
How can you do such a short cycle time?
Apart from the short runtime, a short cycle time needs a quick cooldown to get the system ready again. The low thermal mass of our heating capillary, the two powerful fans in the helix tower and the cooled helix tower itself are important pieces of this puzzle. This combination allows us to do cooldowns from 300 °C to 40 °C within approx. 10 seconds.
I have heard other terms like Hyper-Fast GC or FF-TG-GC. What is the difference to a Chrom GC?
There is no difference! These three terms are synonyms of the same instrument. FF-TG-GC, or Flow Field Thermal Gradient Gas Chromatography, is the scientific name for the HyperChrom GC aka Hyper-Fast GC.
Troubleshooting
How do I proceed when observing an issue with a HyperChrom GC?
This Troubleshooting section of our FAQs is meant to help with minor problems you might face. Even when prepared with utmost care, the recommendations given are general advise; they are per definition not comprehensive information and not suitable to every situation. HyperChrom thus assumes no liability for any harms and issues arising from persons conducting work on the instrument following these recommendations. For the bigger picture, please also check the manual for advice. Whenever in doubt, please contact us via service@hyperchrom.com so that we can react to your particular situation and, if necessary, send one of our experts to your assistance.
I need help with my device. What can I do?
Whenever you need help with your HyperChrom GC, please contact us via service@hyperchrom.com – this is the quickest and easiest way for us to help you. We will help you with your issue and are ready to send our experts to you for on-site support.
Can I perform maintenance tasks on the instrument myself?
When creating the HyperChrom GC, we focussed on a user-friendly design. Therefore, we made any component of the GC as accessible as possible. After an appropriate training with our experts, you are welcome to conduct maintenance on the instrument yourself.
The GC is not getting ready. What is the problem?
There are a lot of possible reasons for that. Please look at the GC's status screen – from firmware 2.13 or higher (see the top right corner of the screen), all relevant values are shown in yellow if not ready and in green if ready. This helps you finding the problem. For firmwares earlier than 2.12, this function needs to be activated by pressing A in the home screen. If you are using a PC software, mind that you might not see all relevant values as some are typically hidden. The software's help function will show you how its status screen can be interpreted.
The pressure in the injector cannot be reached/maintained. What can I do?
The most common cause is that the system is leaking. It is advisable to check for leaks with a leak detector and tighten the appropriate screws on the gas line. If this is not sufficient, check if the column is correctly installed and that the graphite ferrule is intact. It may be necessary to replace it and shorten the column. Another possible cause is a leaky liner O-ring or septum that e.g. has become too old, is damaged or was not positioned correctly. Please consider changing those consumables and check their positioning.
The pressure in the detector (MS) cannot be reached or the Air/Water check shows too high signals. What can I do?
Please make sure that the MS had enough time to create the needed vacuum. During this process, it is perfectly normal that air/water checks present high values. Consider waiting for several hours and re-do the air/water check to monitor possible trends. If values are decreasing, it is likely that your MS needs/needed more time to create an appropriate vacuum – a prerequisite of satisfactory chromatography. Wait for the values to become sufficient and reproducible before going on with chromatographic measurements. Furthermore, there might be a leakage in front of the detector entrance. It is suggested to carry out a leakage search with dry, oil-free, compressed air as a leakage spray. Check that the transfer line (if installed) is seated correctly and that no circulating air is drawn into the detector. The transfer line may have to be replaced or shortened and reinstalled. Then carefully tighten the screws. Further possible causes are leakages somewhere in the system which are potentially possible in any point of connection, e.g. in the injector, or caused by a broken column. In any case, please refer to the manual of your MS or contact its manufacturer before starting to find and validate the best approach.
Why do the heated zones not heat up?
There are several simple explanations for heated zones not heating up. At first, please check whether you switched the heaters on (e.g. by pressing H on the keyboard or via a right-click context menu's option on the software's HyperChrom GC schematic drawing). You can check whether or not the heaters are switched on by having a look on the GC's screen that shows the heaters' current state on the bottom part of the status screen.
Please also check whether the green LED on the left side of the device's front is illuminated. This status LED is illuminated if the heaters' safety switch is active, allowing the heaters to rise the temperature. If the LED is not illuminated, the safety switch is inactive, forcing the heaters to cool down. This is an independent safety feature preventing the instrument from heating up too much even if the relevant temperature sensors are failing. The safety switch needs to be activated manually by pressing the respective button after powering up the device
As a third possibility, please check whether the instrument shows an error message. Error messages and their causes might stop the instrument from heating up for safety reasons. If you are sure that the causes of error are resolved, you can dismiss the error message using the respective button in the control software (if in remote control mode) or by pressing E on the instrument's keyboard.
Please also check whether the green LED on the left side of the device's front is illuminated. This status LED is illuminated if the heaters' safety switch is active, allowing the heaters to rise the temperature. If the LED is not illuminated, the safety switch is inactive, forcing the heaters to cool down. This is an independent safety feature preventing the instrument from heating up too much even if the relevant temperature sensors are failing. The safety switch needs to be activated manually by pressing the respective button after powering up the device
As a third possibility, please check whether the instrument shows an error message. Error messages and their causes might stop the instrument from heating up for safety reasons. If you are sure that the causes of error are resolved, you can dismiss the error message using the respective button in the control software (if in remote control mode) or by pressing E on the instrument's keyboard.
My device is suddenly cooling down during the run and showing the „Supply Sens” error message
This is a safety precaution preventing overheating. Typically, this is caused by the temperature and the gradient fan programmes accidentally contradicting each other, e.g. setting the heating capillary to a very high temperature while applying a very strong cooling gradient. Please carefully check your temperature and gradient fan programmes for such pairings.
My instrument is aborting the run and cooling down during heating up. It also displays the „Column Max Temp” error message. What does this mean?
This is a safety feature protecting the separation column inside the heating capillary in case of the actual temperature surpassing the column's maximum temperature during the run. Please increase the column max temp (if appropriate) or choose a temperature programme working at lower temperatures. Mind that with chosing a temperature programme that has temperatures nearly as high as the column's defined maximum temperature, this error might occur occasionally only with control mechanisms shortly overdriving. Adjust the temperature programme or the column's maximum temperature to avoid this.
Why do I need to re-adjust the IR sensors regularly? What might happen if I don't?
If the position of the IR sensors is incorrect, temperature readings of the heating capillary will be incorrect as well, resulting in the heating capillary heating up more than intended. Ultimately, this will damage both your separation column and the heating capillary itself. To prevent this, the position of the IR temperature sensors needs to be checked regularly, particularly if you conducted work on the device before. This way, you are likely to detect a shift of positions (caused e.g. by vibrations) before it becomes critical. We recommend to check and adjust the position daily and before restarting the device. To do this, you need the enter the „Calibration“ or „CheckPos“ mode of the instrument and proceed as described in the manual.
The instrument does not react to keyboard input.
We assume that the device is switched on, indicated e.g. by the illuminated on/off switch and screen. If not, please carefully check the wire and the plug and switch the instrument on using the on/off switch.
Also, the device could be in Remote Control mode (indicated by a blinking RC icon on the top of the GC’s screen). If controlled remotely, e.g. using a CDS system or the HyperChrom GC Control software, the instrument blocks any entry from the keyboard and gives priority to entries from the respective software
Finally, the instrument might block most keyboard input due to an unresolved error message. The error state is indicated by a red line at the screen’s bottom, giving information about the type of error. If you are sure that the error is resolved, you can dismiss the error message by pressing E on the keyboard or reacting to the error using the respective software. The GC will not accept any other keyboard input until the error state is dismissed
Also, the device could be in Remote Control mode (indicated by a blinking RC icon on the top of the GC’s screen). If controlled remotely, e.g. using a CDS system or the HyperChrom GC Control software, the instrument blocks any entry from the keyboard and gives priority to entries from the respective software
Finally, the instrument might block most keyboard input due to an unresolved error message. The error state is indicated by a red line at the screen’s bottom, giving information about the type of error. If you are sure that the error is resolved, you can dismiss the error message by pressing E on the keyboard or reacting to the error using the respective software. The GC will not accept any other keyboard input until the error state is dismissed
What is this ultrasonic device and how can I recharge it?
The ultrasonic device we provide with delivery is meant as an aid for changing separation columns. Using it on the heating capillary - ideally in the middle and near a holding clip - drastically reduces the friction within the heating capillary, facilitating column exchange. For recharging, please do not use USB ports or charging cables provided by or meant for most other devices, e.g. laptop charging cords or PC USB outlets. Please use a direct adapter from your power socket to USB and the provided charging cable to charge the ultrasonic device. If the device is charging correctly, the control LED shows a red light (this might take a few minutes of charging). Once fully charged, the LED's colour changes to green.
What is the SD card for?
The SD card is used to store configuration information that are important for a flawless function of the instrument. It cannot be used to transfer measurement data – all connections from the instrument to a PC is realised via USB. Please do not remove the SD card unless you are specifically told to do so by our technicians.
How do I write a method using the GC only? What is an event table?
By pressing P on the homescreen, you enter the method parameters of the instrument. The method parameters consist of the main method parameter screen and the following event tables for pressure, temperature, gradient and valve programmes, accessible via N (for Next) or B (for Back). There you can define the desired values over time for each of those parameters – to do that, navigate to the right parameter using the arrow keys, press C to change a value, insert the desired value and press Enter. Return to the home screen by pressing H. For detailled instructions, please refer to the manual.
Do the pressures displayed by the system refer to absolute or relative pressures?
Most displayed pressures are given as absolute pressure while the pressures of Split and Purge are given as relative pressure. Absolute pressure is always approx. 100 kPa higher than relative pressure as absolute pressure already includes the atmospheric pressure of the ambient air. This is why Split and Purge use relative pressure as they are directly leading to open ambient air and need to take its fluctuating pressure into account.
How can I prevent peaks shifting after changing the column?
Under some circumstances, e.g. if you prefer shortening the separation column after several runs, changing the separation column to a new one might result in slight shifts of peak retention times. This is e.g. caused by slightly varying column lengths and might lead to a decreased resolution with complex temperature programmes. To overcome this, we recommend to do an example run after changing the column and using our Finetuning tool afterwards to quickly adapt your temperature programme. That way, you will be back at the resolution you are used to within minutes. Please contact us via service@hyperchrom.com if you need access to our Finetuning tool or if you need further help.
How long does it take for the instrument to change between Standalone mode and Remote Control mode ?
The instrument needs a short time of around 10 seconds to switch between Standalone mode (in which the instrument is controlled via keyboard directly) and Remote Control mode (in which the instrument is controlled via a connected PC, while the instrument's keyboard is locked to prevent input conflicts) and vice versa. Please do not make changes within that period as they might not be effective. The instrument switches from Standalone to Remote Control automatically as soon as a functioning Remote Control setup is available, indicated e.g. within the PC's control software or by the „RC“ icon shown on the instrument screen'S top row.