PART NO. 9999-51270-8

  •  Bright 3.5-Inch TFT Color Display

  • Dimmable Backlight and Night Display for Pilot House Applications

  • Easy Calibration and Setup from Front Panel

  • User Configurable 250, 350, 450, 650 RPM Ranges, Forward & Aft Station Orientations

  • Accepts 4-20mA or +/- 10V input signals

EMI’s Digital Shaft Tachometer System uses the latest digital technology to accurately and 

dependably measure the speed and direction of propeller shaft rotation. Proximity sensors, digital technology and customized meters are central to the EMI design.


The Digital Shaft Tachometer features a bright 3.5 inch TFT color display. Shaft RPM is displayed in both large easy to read digital and analog formats for viewing up to 15 feet away.

Front panel dimming controls allow for easy adjustment of the display backlight to accommodate any ambient lighting condition.

The meter uses an input voltage or current signal originating from a separate sensing device (not supplied) to display shaft revolutions. Meter calibration is accomplished through easy to follow menus using front panel keypad.

On-Console Bracket and In-Console mounting options are available.

CAGE CLAMP®† and MINIFAST/EUROFAST®‡ connection options are available to allow for easy installation to existing shipboard cables and daisy-chaining of multiple indicators.



PART NO. 9999-44490

Three Shaft Tachometer panels are provided in the pilothouse. One is mounted in the center console, and one each in the port and starboard side consoles. The shaft tachometer panel has two meters which display Port and Starboard main engine RPMs.


PART NO. 9999-50090

The proximity pick-up junction boxes each include two inductive proximity sensors which are mounted alongside the shafts to be monitored.  Two steel targets are mounted on the shaft 

coupling so that as the shaft rotates each pick-up sensor produces a pulse signal when its 

corresponding target passes by the face of the sensor.  


The proximity pickups are connected to a junction box which provides a connection point to 

downstream shaft tach equipment.  This equipment uses the pulses from one pick-up to determine shaft rotational speed based on the number of pulses detected in a defined time period. The 

positions of the two targets are offset from one another approximately ½” along the shaft’s axis.  The shaft tach  equipment uses the pulse from this second offset sensor to determine the direction of the shaft’s rotation based on the occurrence of the pulse with relation to the speed pick-up’s pulse. 

ENGINE MONITOR, Inc., 191 James Drive West St. Rose LA, 70087 • +1 504. 620. 9800 Fax: +1 504. 620. 9801 • [email protected] • © 2015 Engine Monitor, Inc. All rights reserved