End Devices
The AT Series tachometer is a rugged instrument with solid-state circuitry for indication of engine RPM. It is equipped with a ring nut for mounting into a standard 3-3/8 in. (86 mm) dash mounting hole. A full 240° sweep of the pointer gives an accurate indication on a large easy–to–read scale, and the dial can be illuminated for night reading.
The ATH Series model is also equipped with hourmeter to record the elapsed running time of an engine. These instruments are designed to function with Alternator, Magnetic Pickup or Ignition signals from:
· Pulses generated by an alternator with 4, 8, 12, 14 or 16 poles on the rotor (3 - 52 PPR)
· Pulses obtained from the ring gear of an engine by means of an electromagnetic sensor (magnetic pickup). The instrument is designed to function with flywheels having anywhere from 50 to 300 teeth
· 2 - 10 cylinder, 4 cycle spark-ignited engines. Not intended for use with Capacitive Discharge (CD) ignitions or magnetos, only for inductive, automotive-type ignitions
The tachometers are powered by a 12- or 24-volt battery and are reverse polarity protected. These units are for negative ground or isolated electrical systems. They are specially designed for use on truck, marine, industrial or stationary engines.
Sales Bulletin: AT & ATH Series
1511813 rev. 2016/11/30
Installation Instructions: AT & ATH Series
00-02-0986 rev. 2016/09/14
Tachometers & Tach/Hourmeters: AT & ATH Series
00-02-0790 rev. 2016/10/04
Sales Bulletin: Magnetic Pickups
1511775 (00-02-0181) rev. 2016/02/25
The VS2 Series switches are shock-sensitive mechanisms for shutdown of engine or electric motor powered equipment. It is designed to detect shock/ vibration in three planes of motion. These fully adjustable switches use a magnetic latch to ensure reliable operation. Explosion-proof EX models for hazardous locations are available.
Ideal for use on engines, pumps, compressors, heat exchangers and pumping units, the VS2 Series can be used where shut-down protection from damaging shock/vibration is desired. Switches are field adjustable to the sensitivity required in each application.
Pushing the reset button moves the tripping latch into a magnetically held position. A shock/vibration will move the magnet beyond this holding position, thus freeing the spring loaded tripping latch to transfer the contacts and shut down the machinery.
Sales Bulletin: VS2 Series
96013 rev. 2016/09/07
Installation Instructions - Shock/Vibration Control Switches
00-02-0185 rev. 2016/05/16
VS94 Series is an electro-mechanical device designed to protect equipment from damaging shock or vibration. This sensitive mechanism can detect excessive shock or vibration and shut down the equipment before further damage occurs. A set of contacts is held in a latched position through a magnetic latch mechanism. As the level of shock or vibration increases, an inertia mass exerts force against the latch arm and forces it away from the magnetic latch causing the latch arm to separate and to operate the contacts.
Sensitivity is obtained by adjusting the amount of air gap between the magnet and latch arm plate. The VS94 Series is housed in a NEMA 4/4X glass-filled polyester enclosure and has a base mount. It is for applications in non-hazardous locations. VS94 models are rated up to 480 VAC.
Applications for the VS94 include all stationary types of machinery or equipment where excessive shock/ vibration can be damaging or poses a threat to normal operations.
Sales Bulletin: VS94 Series
94092 rev. 2017/07/12
Installation Instructions - Shock/Vibration Control Switches
00-02-0185 rev. 2016/05/16
The SHD30 and SHD30-45 are microprocessor-based tachometers with hourmeter and an overspeed trip point. The trip point can be connected as either a form C relay output or as a normally open SCR output for alarm or shutdown on overspeed. The SHD30 features a panel-mounting design, plastic enclosure that is 5-1/16 (129 mm) long and 4-1/4 in. (108 mm) high.
The SHD30-45 has the same enclosure, but it also has a backplate with studs to mount like an OPLFC. The SHD30 models power and RPM data are supplied by either a magnetic pickup or a capacitor discharge (CD) ignition. The hourmeter is adjustable to a preset time and resettable to zero. Should power be lost, onboard batteries maintain the run hours display and allow for resetting the overspeed relay output.
When a tach signal is present the SHD30 models display RPM. When a tach signal is not present, the display is blank unless the Read Hours membrane key on the faceplate is pressed and held. The five-digit, liquid crystal display is updated every second. The run hours, overspeed set point and current pulses per engine revolution can be displayed by manipulating the membrane switches. Run hours can be displayed even after power is lost. The run hours display can be configured to alternate with the RPM display.
Sales Bulletin: SHD30 & SHD30-45 Models
97050 rev. 2015/09/28
Installation Instructions: SHD30 & SHD30-45 Models
SHD3-97051N (00-02-0288) rev. 2003/05
Installation Diagrams: SHD30 & SHD30-45 Models
20-08-0258 rev. 1996/08/21
The Murphy Selectronic MT90 digital tachometer offers high accuracy and dependability resulting from use of a quartz crystal time-base and digital, solid-state electronics. Tachometer power is supplied by either a Murphy magnetic pickup mounted at the flywheel ring-gear of an engine or by a 12-, 24- or 32-volt DC battery system.
RPM data is supplied by either a Murphy magnetic pickup or by the alternator in your battery charging circuit. The MT90 tachometer also has backlighting for easy readings in low-lit areas. This lighting requires a battery power source.
The MT90 is calibrated to engine RPM by setting a series of calibration rotary switches on the back of the tachometer. The proper switch sequence for the engine is determined by (1) the number of ring gear teeth for the magnetic pickup or (2) by the ratio of alternator to engine pulley diameter and the number of poles of the alternator.
Typical applications include: generators, compressors, industrial engines, oil field equipment, marine vessels, vehicles, farm equipment and construction equipment.
Sales Bulletin: MT90 Model
9004 rev. 2016/05/04
Sales Bulletin: MT90 Model
00-02-0068 rev. 2016/03/03
Murphy Time Switches can automatically start or stop engines or electrical motors after a predetermined time. These time switches can be wired for an open or closed circuit when time expires. They require no electrical current to operate and have an SPDT contact arrangement. These switches feature a precision movement that gives years of reliable service. The switches’ precision movement can be set to zero anytime, and a built-in stop prevents overwinding.
Two versions are available: an hour switch for setting run time and shutdown of equipment; and a minute switch for short interruption of Swichgage circuits on test or start up.
The 12T (12 hour) and 24T (24 hour) time switches are enclosed in a NEMA 4 weatherproof enclosure. A hinged, gasketed cover and 1/2 NPT conduit connection allow for a dust-tight installation. The enclosure includes a clasp and eye for a padlock to prevent unauthorized operation. Instructions for popular engine applications are secured inside of the lid.
The 5T (5 minute) and 15T (15 minute) timers mount directly in control panels for short range timing with manual reset.
These switches are perfect for disconnecting shutdown circuits while equipment is being started. Murphy Time Switches are designed for use in the oil field, irrigation systems or anywhere equipment must operate or be controlled for a predetermined time. Mounted on a post or in a panel away from vibration and shock, these time switches give accurate, longterm service.
Sales Bulletin: Models 5T, 15T, 12T, 24T
96095 rev. 2014/11/01
Sales Bulletin: Models 5T, 15T, 12T, 24T
00-02-0073 rev. 2013/01/24
