The TD-4100 XDC General Purpose oil in water monitor is a lower cost version of the industry standard TD-4100 XDC and is designed for General Purpose areas (non-explosive atmospheres). It was designed for normally clean water applications or dirty water applications where fouling can be controlled by chemical injection or optional on-board cleaning systems. It utilizes a clear tube flow cell to contain the sample water at pressure to prevent oxygen contamination in steam systems and to return the sample to the process at pressure. It uses a unique internal Cell Condition Monitor to alert operations of the need for cleaning or to trigger the optional on-board cleaning system.