PlasmaDetekProducts015

Flow Transducer

The flow transducer is the biggest source of contamination for

such analyzer. To avoid any problem with such device, the

transducer is installed at the end of the flow path after the

detector and is connected to the microcontroller unit to give

information to the micro-valve to control a stable flow.

So why not using a MFC after the detector? That would avoid

any chance of contamination or leakage? Actually, the PED

must work at atmospheric pressure and it must not be

pressurized. Since the PED is a cell made of quartz, it can

break with a backpressure coming from the vent.

Furthermore, you want to keep a constant pressure in the

detector to get a stable plasma.

NO NEED OF ZERO CALIBRATION GAS!

An option is available that avoids the need of a pure reference gas to make the zero calibration. The LD8000 can be designed in a way

that components are added inside the analyzer to generate zero gas.

Only the sample gas is connected to the instrument and zero calibration can be achieved. A valve’s system is used to change the flow

path to the detector. During zero calibration, the sample goes to a small gas purifier to get pure argon or helium.

There is no consumable in such configuration. Since the integrated gas purifier is used only during zero calibration and the valve

system isolates it, the lifetime of the purifier is extended. Such system will save the needs of pure argon supply, gas regulator, piping,

external purifier, bypass valve for the purifier, etc. The payback is quite evident!

Figure 7

Flow path of the LD8000

Figure 5

Standard valve performance

Figure 6

LDetek valve performance

Sample vent

1/8 compression

fittings

Flow Transducer

Plasma Detector

Humidity Control

Device

Micro-Valve

Sample inlet

1/8 compression

fittings