SWITCH AS 3L6306 - Caterpillar

Caterpillar SR4B generators are provided with voltage regulators. However, oilfield generators are not provided with voltage regulators. The voltage regulator controls the generator output voltage. Different types of voltage regulators that are available with SR4B generators are listed in table 1.
Table 1
Voltage Regu-
lator     3306B
gen-
sets     3406C
gen-
sets     3406E
gen-
sets     3412C
gen-
sets     3500
gen-
sets    
VR3     Stand-
ard     Stand-
ard     N/A     N/A     N/A    
VR3F     Option     Option     Stand-
ard     Stand-
ard     Option    
VR6     Stand-
ard     Stand-
ard     Stand-
ard     Stand-
ard     Option    
VR4     Option     Option     N/A     N/A     N/A    
DVR     Option     Option     Option     Option     Stand-
ard    Illustrations 1 through 5 show the adjustment controls on different types of voltage regulators.The VR3 and VR3F regulators have an adjustment for voltage droop 1. The VR4 regulator does not have an adjustment for voltage droop. The VR4 regulator is not designed for parallel applications.The VR3, VR3F and VR4 regulators have a voltage level control (2) .The VR3 and VR4 regulators have an adjustment for voltage gain 3. The VR3F regulator does not have an adjustment for voltage gain.Voltage droop, voltage level and voltage gain are controlled by multiturn potentiometers. The adjusting screws on the potentiometers do not have a fixed stop. When the potentiometer reaches the end of adjustment, a ratchet action begins. The beginning of a ratchet action can be felt with the adjusting tool. The adjusting screw can be turned past the potentiometer stop (ratchet action) without further changing the potentiometer setting.The VR6 is an analog regulator. There are five adjustments on the VR6 regulator:
Adjustment for droop
Factory calibration of the voltage adjustment range
Adjustment for voltage
Adjustment for knee frequency
Adjustment for stabilityThe factory calibration of the voltage adjustment range (12) should not be adjusted by the user.The DVR is a microprocessor based voltage regulator. All the parameters are preset at the factory. The parameters can be modified in order to meet the specific requirements on the site. Certain system parameters can also be monitored on the display (5) of the DVR. Keypad (9) is used to change the information that is shown on the display (5). J1 connector (10) is used to join the DVR to a personal computer. Screw terminals (11) are used to join the DVR to the generator and various customer options.
Illustration 1 g00626329
Adjustment Controls of the VR3 Regulator (1) Voltage droop potentiometer (2) Voltage level potentiometer (3) Voltage gain potentiometer (4) Fuse(s)
Illustration 2 g00626331
Adjustment Controls of the VR3F Regulator (1) Voltage droop potentiometer (2) Voltage level potentiometer (4) Fuse(s)
Illustration 3 g00871658
Adjustment Controls of the VR6 Regulator (12) Factory calibration of the voltage adjustment range (13) Voltage adjustment
Illustration 4 g00626398
Adjustment Controls of the VR4 Regulator (2) Voltage level potentiometer (3) Voltage gain potentiometer (4) Fuse(s)
Illustration 5 g00626333
Digital Voltage Regulator (DVR) (5) Display (6) Function key (7) Scroll down key (8) Scroll up key (9) Keypad (10) J1 connector (11) Screw terminalsAdjustment Procedure for the Voltage Regulators
VR3 Regulator
Note: The