TOF-MS Voltage Controller
The Kore TOF-MS Voltage Controller contains modules to address four tasks:
A high voltage supply provides the excitation for an electron multiplier type detector. The output voltage, for driving a multiplier, is adjustable from 0 to 2.5kV via a front panel ten turn potentiometer. The supply can be floated to facilitate arrangements where modest post acceleration of ions is employed, or where other considerations require the detector first dynode voltage to be independent of the multiplier excitation. Two low voltage signal inputs are available to enable or disable the detector excitation. These can be used, for example, to provide computer control and interlock protection for the detector.
Two general purpose high voltage resistor chains are intended to allow one power supply to be used to drive several electrodes in the spectrometer, whilst still allowing independent adjustment. Each chain accepts an input of up to ±5 kV which is applied to the top and is available as an output. A further four lower voltage taps are provided on each chain, each having an associated front panel ten turn dial potentiometer. The boards are designed so that the tappings may be readily moved to anywhere between the top of the chain and earth, with the potentiometer providing approximately 6% of adjustment for fine control. The two chains are completely independent so that one may be operated with the opposite polarity from the other, which is often useful in practice.
A set of four high voltage, normally open relays are provided, with their coils wired as two pairs and driven by a polarity changeover input. The high voltage contacts are connected to four high voltage BNC connectors which allow a swapping of connections according to the polarity input. The most typical use for these would be to automatically swap the polarity of a pair of high voltages when changing between positive and negative ion detection. However, they may be used for any purpose compatible with the voltage rating. A pair of low voltage output BNCs are also provided with contact closures that follow the polarity input state. These could be used for additional external relays if required, or to slave the control of some other external unit.
Finally there are two +5V supply sockets available, intended for driving external modules, perhaps extra relays or high voltage CMOS switch modules.
Last updated: 13 September 2005 22:03
© Kore Technology Limited 2005