The NGX maximum level switch is a TUV design approved safety component to protect refrigerant compressors against liquid carry-over. At maximum allowable liquid level within the surge drum a connection DN 32 is required to weld-on the stop valve that belongs to the scope of supply of the maximum level switch. The NGX limitation switch is screwed into this stop valve (backseating) and the junction box is mounted with the supplied bracket at the valve. The junction box has a light emitting diode (LED) that is illuminated during normal operation. Furthermore a relay BNRt for installation in control cabinet belongs to the scope of supply. For further information regarding design, installation or operation please see our instruction manual!