0433395 JOHNSON THERMOSTAT AY.

The 6V4060 Engine Set Point Indicator Group can be used for measurements of the set point R/MIN (revolutions per minute) of Caterpillar diesel engines. The set point [formerly called the balance point] is 20 R/MIN more than the full load R/MIN of the engine. Because of this, 20 R/MIN must always be subtracted from the measured set point to find full load R/MIN. This is a new, more accurate method of measuring full load R/MIN on Caterpillar engines. The LUG and OVERRUN indicators on the front panel of the set point indicator are controlled by sensitive electronic circuits, and are used to accurately locate the set point of the engine. The set point R/MIN is then read directly on a tachometer. If the 6V2100 Multitach is used, it can be installed on the set point indicator as shown above. This permits the digital readout to hold constant for a short time at the set point R/MIN allowing the set point R/MIN to be more accurately read. All connections necessary for operation of the multitach are provided for by the set point indicator.The 6V4060 Set Point Indicator, with the 6V2100 Multitach installed, can be easily stored in the space provided in the 6V3150 Engine Pressure Group as shown. With this arrangement, the engine pressure group can be used to measure engine speed, set point and pressures. Because all of the multitach input connections are easily accessible on the front panel of the set point indicator, the multitach and set point indicator can be used while installed in the case as shown.The set point indicator has two independent input channels. This permits power balancing of twin engine installations. The set point for either channel can be held for three seconds on the multitach digital display to allow easier reading. A selector switch determines which engine speed reading will be held. Each channel has two indicator lights to show where the engine is operating on the load curve, and to show when the set point has been reached. The OVERRUN indicator light (1) is on when the engine is not fully loaded and the rack contact is open or is making contact less than 10% of the time. When the engine is fully loaded and the rack contact is closed or is making contact for more than 75% of the time, LUG light (2) will be on. The set point of the engine is indicated by OVERRUN light (1) going off as an increasing load is slowly applied to the engine and the rack contact makes contact just over 10% of the time, but not more than 75% of the time. After both lights have been off for 3/4 of a second, both the OVERRUN and the LUG lights will come on together if MULTITACH HOLD SOURCE switch (3) is not in the OFF position. If a 6V2100 Multitach is installed, NO INPUT SIGNAL light (4) will come on bright and the digital display reading of the set point will be held for three seconds; then all three lights will go off. The set point is read during the three seconds that the multitach reading is held. After the three second hold period, the multitach reading may decrease for several seconds, then return to actual engine speed.Components Of The 6V4060 Engine Set Point Indicator Group
1. Engine Set Point Indicator2. 1P7446 Rack Contact Cable3. 6V4949 Fastener Strips (for securing 6V2100 Multitach)Optional Items For Use With The Engine Set Point Indicator Group
Features And Specifications Of The Engine Set Point Indicator
HIGH ACCURACY MEASUREMENTS: High accuracy set point R/min measurements are possible using the engine set point indicator. Electronic circuitry eliminates errors caused by operator interpretation of test light brightness, low batteries, or high rack contact resistance.REPEATABLE MEASUREMENTS: Set point measurements of the same engine are usually repeatable within 5 R/min, depending on how accurately the load can be controlled and repeated. Stable, regulated voltages and electronics makes this possible.DIRECT SPEED READOUT: By mounting a 6V2100 Multitach on the set point indicator, direct readout of set point speed is possible. At the set point, the speed reading is held constant for three seconds, allowing it to be easily read.TWIN ENGINE BALANCING: Dual channels with separate indicators allow twin engine installations to be easily balanced. Applications include marine installations, compound mechanical drives and generator sets.LED INDICATORS: All indicators are light emitting diodes (LED's) for long life.INPUT POWER REQUIRED: External power source of 11 to 40 Volts DC at a maximum of 1 Ampere. The engine battery or other external power source can be used.OVERRUN INDICATION: The OVERRUN indicator will light whenever the engine rack contact is open and/or has contact less than 10% of the time.LUG INDICATION: The LUG indicator will light whenever the engine rack contact is closed and/or has contact more than 75% of the time.SET POINT INDICATION: Engine set point is indicated by the OVERRUN light going off, and both the OVERRUN and LUG lights staying off. After both lights have been off 3/4 of a second, both lights will come on together for three seconds to indicate set point has been reached.RACK CONTACT TEST CURRENT: A direct current of 0.1 Ampere at 5 Volts is applied to rack contact during the test.R/MIN READOUT: A 6V2100 Multitach can be mounted on the engine set point indicator to directly display the engine R/MIN.MULTITACH HOLD FEATURE: The set point R/MIN will be held on the multitach for approximately three seconds to allow it to be easily read. This is done automatically by removing the multitach input signal for three seconds. This causes the last speed reading to be held on the digital display.DUAL CHANNEL: Two identical separate channels are provided on the set point indicator. This allows twin engine installations to be easily balanced.SELECTABLE HOLD SOURCE: Since only one multitach is used, a switch is provided to allow the set point of either engine on twin engine tests to hold the reading on the multitach.ELECTRICAL ISOLATION: Both set point indicator channels are electrically isolated