Doppler Log JRC JLN-740 Series

The JRC JLN-740 series is a Doppler lag that complies with the IMO MSC.96 (72) standard and can be used on all international vessels with a displacement of more than 300 registered tons. It has high speed measurement accuracy and is equipped with a unique bubble detection system that reports when the measurement accuracy deteriorates due to contact with air bubbles.

The JLN-740 series uses digital signal processing, which, combined with optimization of existing speed measurement signals and reliable mounting, ensures measurement accuracy of up to 0.03 knots or 0.3% in all models.

The main components of the JRC JLN-740 series include a main display (color LCD or 4.5-inch monochrome LCD), a distribution processor (only for the JLN-740A/N model), a signal processor, an assembly converter and a remote maintenance system (RMS) compatible.

The JRC JLN-740 series is compatible with JRC's patented Remote Maintenance System (RMS), which uses VDR (Voyage Data Recorder) and JRC satellite communications to remotely communicate with equipment on board the ship and conduct remote diagnostics and preventive maintenance.

The technical specifications of the JRC JLN-740 include an operating frequency of 2 MHz for measuring speed relative to water, a range of measured speeds from -10 to +40 knots (backward/forward), a speed measurement accuracy of 0.1 knots or 1%, whichever is greater, a distance measurement range from 0.00 to 99999.99 nautical miles.

The JLN-740 power supply can be AC from 110 to 230 V (90 - 235 V), 50/60 Hz ± 5%. The power consumption is 50 watts for the JLN-740A model, 45 watts for the JLN-740N model and 20 watts for the JLN-741A/N model.

The operating temperature range is -15°C to +55°C for all equipment except radiators, and -3°C to +40°C for radiators.

Software versions include NJC-70S - R01.00, NQA-7040- R01.00, NWZ-510 SWD - 1.001 and NWZ-4640 - R74.01.