The Ex-amplifier SS 400 Ex can evaluate the EGE flow sensors for areas that could have gas or dust explosions as classified by ATEX. The classified category 2 equipment can be easily operated post installation, in zones 1 or 21. The desired limiting value for the connected flow switch can be set on site itself using an LED chain. The relay output can be operational with type ‘intrinsic safety’ or ‘increased safety’ protection. The switching signal can easily be routed to the control room from the hazardous zone. The unit complies with the requirements of protection type ‘m’/molded, increased safety/’e’ and intrinsic safety type/’i’ protection. Having an ia protection, the sensor circuit is intended for the connection of an ATEX-certified EGE.