Speed Log ppm to NMEA 0183 converter

NM-251B is a Speed Log ppm to NMEA 0183 converter that enables connection of every speed log that uses the ‘’closing’’ contact interface (either relay contact or opto-coupler output) with digital systems and instruments that comply with NMEA 0183 standard.
NM-251B is capable of converting the speed log contact closures to a standard NMEA $VWVHW string with checksum error control and output at TLL, RS-422 and RS-232 signal levels.
NM-251B is certified to IEC 60945 for use on board SOLAS vessels.
Typical applications include the connection of speed log ppm output to navigation systems with NMEA 0183 input like radars, VDR, ECDIS.