Type 8710 controls the mass fl ow of gases through a sensor elementwhich is not in direct contact with the gas itself. The measured valueprovided by the sensor (see the description on page 2) will be comparedin the digital control electronics with the predefi ned set point accordingto the signal; if a control difference is present, the control value output tothe proportional valve will be modifi ed using a PI-control algorithm. In this way, the mass fl ow can be maintained at a fi xed value or a predefi nedprofi le can be followed, regardless of pressure variations or other changesin the system. Type 8710 can optionally be calibrated for two different gases, the user is able to switch between these two gases.The control element, a proportional valve working at low friction, guaranteesa high sensitivity and a good control characteristics of the unit.

Typical application areas are gas dosing or rather the production of gas mixtures in:

• Heat treatment,

• Metal melting treatment,

• Environmental technology,

• Material coating and