Why did the multiplier autotune voltage suddenly jump by several hundred volts after several months of stable operation?

This is the typical symptom of a vacuum accident, where the multiplier voltage was left on during venting or where high pressure in the chamber has caused pump oil to backstream.

This can also be caused by a power failure or instrument malfunction. Labs where there are many different users, such as teaching labs, are prone to this problem (due to a less-experienced operator).

If the problem resulted from pump oil backstreaming onto the multiplier while no voltage was applied to the multiplier (and it was not used afterwards), then the multiplier can be cleaned in an Ultrasonic bath using a non-polar solvent (such as heptane - see care and handling brochure BR-0061-A for details). This may restore performance, otherwise a new multiplier must be purchased.

This situation is the same for all types of multipliers and is a fault in the mass spectrometer and not in the electron multiplier.


Do you have a replacement multiplier for X (instrument make and model)?

Yes. See the instrument selection guide.


Are ACTIVE FILM multipliers made from Beryllium-Copper?

No. ACTIVE FILM Multipliers use a new air-stable dynode material and can be handled and stored in the same way as standard multipliers.


Why are ACTIVE FILM Multipliers superior to other types of electron multipliers?

ACTIVE FILM Multipliers integrate the best features of continuous-dynode and discrete-dynode detectors. In GC-MS applications they generally exhibit higher sensitivity, wider dynamic range, and longer life time than other detectors. They are completely air stable and offer better signal stability.

ACTIVE FILM Multipliers have very reliable and uniform performance and every ACTIVE FILM Multiplier is fully tested at the factory for operation and performance.


What are ACTIVE FILM Multipliers?

ACTIVE FILM Multipliers are new, discrete-dynode electron multipliers (ion detectors) for mass spectrometry applications. They are fabricated using sophisticated semiconductor processing techniques to establish a high-yield, air-stable secondary emissive surface.

This technology allows exceptional design flexibility, enabling full optimisation for any mass spectrometry application. ACTIVE FILM MultipliersTM integrate the best features of both continuous-dynode and discrete-dynode detectors in one robust, computer-optimised package.


Do I have to do anything different to install an ACTIVE FILM Multiplier?

No. There is no modification of equipment required by the user.


Will the specified multiplier fit my instrument?

Yes. All ETP detectors are guaranteed to be "plug-in" compatible with the instruments for which they are designed. Installation instructions are included with every multiplier.


Can I get a list of references (users of ACTIVE FILM Multipliers)?

Yes. Contact ETP for information.


Do you have a replacement multiplier for instruments not covered in the selection guide?

For most instruments, the answer is "Yes". Contact ETP for information on specific instruments.


Why should I use this multiplier if it is not the specified brand of the instrument manufacturer?

ACTIVE FILM Multipliers exhibit better performance than conventional CDEM-type detectors. They are currently used in a number of applications by all of the major mass spectrometer manufacturers.


Will my instrument operate the same with an ETP electron multiplier?

Yes. Instrument autotune and analysis functions will be unaffected. Overall performance (i.e. sensitivity, etc.) will, in many cases, be improved.


How can I get information on the multiplier model for my mass spectrometer?

Literature available online includes Product Data Sheets, Installation Instructions, Manuals and Technical Articles. If you require further information, please contact ETP.


What do instrument manufacturers think of ETP Electron multiplier?

ACTIVE FILM Multipliers are installed as original equipment in mass spectrometer instruments manufactured by Hewlett-Packard, Varian , Kratos, Shimadzu, Fisons (VG), Finnigan MAT and PerkinElmer among others.


Is my instrument warranty affected by installing an ACTIVE FILM Multiplier?

Installation of an ACTIVE FILM Multiplier will NOT affect manufacturer's warranty unless specified by the manufacturer.


What if I have any other problems or questions?

Product and applications support is available by contacting SGE.


What is the shelf-life of an ACTIVE FILM Multiplier?

Shelf-life is guaranteed for two years if stored in the original packaging.


Why is my instrument giving poor performance after installing an ACTIVE FILM Multiplier?

Poor performance after installation is almost always related to a problem with the instrument rather than the Electron Multiplier. Instrument performance is seldom different compared to before the multiplier change and in our experience, the vast majority of cases have a problem that is not related to the multiplier.

A true difference in performance is often related to maintenance that is done by the operator on the mass spectrometer at the same time as installing a new multiplier ("since the system is open anyway, why not do everything").


Why do I regularly have to increase the applied high voltage (autotune voltage) to maintain performance?

This is normal for all types and brands of electron multipliers.

Over the life of a multiplier, the voltage applied to it will need to be increased regularly to maintain the gain (performance) of the multiplier. In general, the average rate of necessary voltage increase is greatest in the early months of the multiplier's life. If it has been 1-2 years since a user has had a new multiplier, they may forget this and be surprised when comparing the rate of voltage change of the previous multiplier (at the end of its life) with that of the new multiplier.


What is the warranty on an ACTIVE FILM Multiplier?

The shelf-life is guaranteed for two years. During that period, the unit is warranted against defects in materials or workmanship resulting in failure at the time of installation. Operational lifetime in any given instrument or application is NOT guaranteed.


Can ACTIVE FILM Multipliers be cleaned?

Yes. Although cleaning is not necessary unless the multiplier has been contaminated, multipliers may be cleaned using Heptane or another non-polar solvent. The detector may be immersed in the solvent in an ultrasonic bath. Make sure the detector is thoroughly dry before reinserting in your instrument. For further details, download the care and handling brochure BR-0061-A.


What is the lifetime of an ACTIVE FILM Multiplier?

Operational lifetime will vary based on instrument, application, sample type and usage. In general, ETP Electron Multipliers exhibit lifetimes from 35% to 100% greater than conventional multipliers.