VALVE GP-RELIEF 2003312 - Caterpillar

General
The KCR-760 voltage regulator consists of transformers, transistors, silicon diodes, silicon controlled rectifiers (SCR's), integrated circuits, resistors, and capacitors. The regulators are relatively unaffected by humidity, temperature, vibration, or shock and are not subject to wear from moving parts. Solid state field flashing components rather than relays are used in the field flashing and underfrequency circuits, eliminating the possibility of contact arcing or contact failure.Application
The KCR-760 voltage regulator is designed for operation with brushless synchronous generators. The voltage regulator controls generator voltage by regulating the amount of current it supplies the exciter field.Standard Features, Options And Accessories
Features provided in standard KCR-760 voltage regulators, options available in this series, and various accessories that can be supplied with the generator set voltage regulating system are described in the paragraphs that follow. Where options are specified in the purchase order, the required circuitry changes are made within the regulator at the factory while accessories are parts that mount external to the regulator.A. Sensing The basic KCR-760 regulator utilizes three phase 50/60 Hz sensing. The sensing transformer has a multi-tap primary permitting operation at sensing voltages of 100 - 600 V ac. The standard regulator includes an underfrequency limit circuit that decreases voltage in proportion to the decrease in frequency when speed drops below the UFL operational threshold. The UFL in standard 50/60 Hz sensing regulators is adjusted with an operational threshold of 49.5 Hz for 50 Hz application and 59.5 Hz for 60 Hz application.B. Regulator Input Power And DC Output Input power and dc output - The KCR-760 regulator utilizes single phase, 240 V ac 10% input power and thereby has a rated maximum continuous output of 125 V dc, 10 A; 180 V dc, 15 A one-minute field forcing.C. Field Flashing KCR-760 voltage regulators include solid state field flashing circuitry.D. Voltage Regulator Fuse 1. Standard fuse - Standard KCR-760 regulators are supplied with a 15 A normal blow fuse in the input power circuitry within the regulator. This fuse provides voltage regulator overload protection.2. Optional fuse - In applications where the system does not include a field circuit breaker and generator field protection is required, a smaller fuse may be used. For generator field protection, fuse amperage should be 1-1/2 to 2 times the exciter field current with rated load connected to the generator. Fuse amperage must not exceed 15 ampere or 2/3 open circuit forcing. Fuse must be normal blow type. Do not install time delay type fuse.E. Voltage Adjustment KCR-760 voltage regulators are provided with an internal voltage range adjust potentiometer and an auto voltage adjust rheostat for remote mounting. The auto voltage adjust rheostat permits adjustment of generator voltage approximately 10% from the nominal sensing voltage.F. Parallel Operation Components KCR-760 voltage regulators include a parallel operation reactive voltage droop transformer (T2) and a parallel voltage droop potentiometer (R4). For parallel operation each generator must be equipped with a current transformer for sensing reactive current. The transformer may have either a 1 A or 5