PULLEY 4N4126 - Caterpillar

Illustration 2. The 6V3150 Engine Pressure Group has storage space for the 6V3121 Multitach Group. 1. Weight: 5.0 Kg (11 lb), without 6V2100 Multitach.2. Size: 39 mm x 311 mm x 101 mm (15.5" x 12.25" x 5.50").3. Gauge Accuracies Over Specified Operating Temperature Range: 4" diameter differential: 2% of full scale
2 1/2" diameter single port - SAE Grade "A" (2%-1%-2%)
4. Operating Temperature Range: 4" diameter differential gauge: -1.1 to 60°C(30 to 140°F)
2 1/2" diameter single port: -18 to 71.1°C(0 to 160°F)
5. Overrange Pressures: 4" diameter differential gauges: 15 psi
2 1/2" diameter single port gauges - pressures above full scale destroy gauge accuracy
6. Pressure Media: 4" diameter differential gauges - clean air and gases only, no fluids
2 1/2" diameter single port gauges - air, oil, water, antifreeze, diesel fuel
7. Operating Position: 4" diameter differential gauges - no effect on accuracy if pointer is mechanically adjusted to zero.
2 1/2" diameter single port gauges - no effect on accuracy
The uses of the different gauges in the 6V3150 Engine Pressure Group are listed below.
The 5P6579 Differential Gauge, 4" diameter, is used to measure:
* Crankcase Pressure* Air Inlet Restriction* Exhaust Restriction* Gas Pressure for Gas EnginesThe 6V4016 Gauge (0 to 160 psi), single port, is used to measure:
* Oil Pressure* Air Compressor Cut-in and Cut-out ReadingsThe 6V4017 Gauge (-15 to +60 psi), single port, is used to measure:
* Inlet Manifold Pressure on Turbocharged Engines* Manifold Vacuum on Natural Gas and Gasoline Engines* Power Balancing of Twin Engines in a Natural Gas or Diesel ApplicationThe 6V4018 Gauge (0 to 60 psi), single port, is used to measure:
* Fuel Pressure* Inlet Manifold Pressure on Turbocharged Engines* Cooling System PressureThese uses are examples only but are not the complete list. This group is not limited to "Engines" only, but is a "low pressure" group with many field service uses.
6V3121 Multitach Group
The 6V3121 Multitach Group contains the 6V2100 Multitach and the items needed for its use.
Illustration 3. The 6V3121 Multitach Group.The 6V2100 Multitach is a small digital tachometer that contains a microcomputer which can be programmed by the serviceman to change different input signals into an R/MIN indication which is shown on the front panel readout. It has a range of 40 to 9999 R/MIN with an accuracy of 1 R/MIN. Programming and control of the Multitach is done by use of the touch switches mounted on the front panel. The Multitach can be used as a remote readout phototach, or it can be used with a magnetic speed pickup or tachometer generator.
To prevent possible failures, the electronic components of the Multitach are thoroughly tested at the factory. Several tests are used, including three thermal shocks (heat stresses), and 100 hours of operation at 40 volts DC and at a temperature of 60°C (140°F). After the tests are finished, the circuit assemblies are sealed with a plastic-like material to prevent possible corrosion or other damage.
Components of the 6V3121 Multitach Group are shown in the chart.
Illustration 4. The 6V2100 Multitach. Features Of The 6V3121 Multitach