The OL 410 is a microprocessor-controlled, precision DC lamp source specifically designed to accurately operate tungsten filament lamp standards and calibration sources. The power output range is 150 watts for the OL 410-150 and 200 watts for the OL 410-200. Both units feature output accuracy of ± 0.02% or better, controlled ramp up/ ramp down of the lamp current, and ten (10) element lamp library with individual lamp hours monitors.  The OL 410 replaces the OL 65A Porgrammable Current Source.