Sterilight UV Sensor Assembly 254NM-C1 for all Cobalt PLUS Systems. Sterilight UV Sensor Assembly 254NM-C1 Features: This UV monitor is a true 254nm ultraviolet sensor incorporating individual calibration boards which allows for field replacement of sensor only if necessary. Audible and visual indicators are included as integral components. The Sterilight 254NM-C1 is the UV assembly for the Cobalt Plus series. This sensor reads 254nm from a low pressure high output UV lamp. The 254NM-C1 comes complete with an integral calibration board and 3 of sensor cable with a water-tight connection. The 254NM-C1 can only be used on the Cobalt Plus series. Sterilight UV sensors Viqua Sterilight SC-200 Cobalt Series UV Water Purification System Replacement Parts Viqua Sterilight SC-320 Cobalt Series UV Water Purification System Replacement Parts Viqua Sterilight SC-600 Cobalt Series UV Water Purification System Replacement Parts Replacement Parts for Viqua VH410 Cobalt Series UV Water Purification Systems Replacement Parts for Viqua VP950 Cobalt Series UV Water Purification Systems