LONG BLOCK 20R7197 - Caterpillar

IVR Voltage Adjustment
Voltage adjustments are categorized into two types, manual biasing and analog biasing. Manual voltage adjustment includes fine-tuning the generator output voltage via digital input, EMCP display, or SCADA ( Modbus). Analog voltage adjustment is performed via programmable analog inputs to the EMCP. Analog voltage adjustment provides a voltage control interface for external potentiometers or external control systems, such as switch gear.The generator maximum voltage bias percentage set point must be configured correctly to be greater than the expected bias range. If this set point is not correctly configured, the required voltage bias may not be possible to achieve. The generator maximum voltage bias percentage parameter is accessed with Cat ET Service Tool. The parameter is accessed through the configuration dialog under "Generator AC Monitor" or can be accessed with the EMCP display. Use the following to navigate to the EMCP sub menu.
Press the "MAIN MENU" button on the EMCP.
Use the arrow keys to select "CONFIGURE". Press the "OK" key.
Use the arrow keys to select "ALL SET POINTS". Press the "OK" key.
Use the arrow keys to select "GEN AC MONITOR". Press the "OK" key.Note: All manual voltage biasing is removed and reset to zero when the engine is stopped. Manual voltage bias levels are not carried over to the next startup after an engine shutdown.Digital Inputs
Remote voltage adjustment toggle switches may be used to fine-tune the generator output voltage. The process is accomplished by programming an EMCP digital input for raise voltage and lower voltage. Each activation of the digital input raises or lowers the voltage by 0.2% of rated. When the digital input is activated continuously, the voltage bias is raised or lowered by 0.2% of rated approximately every 400ms.Refer to the Systems Operation, "Digital Input Programming" section in this manual for further details on programming digital inputs on EMCP 4 controllers.Voltage / HZ Control (EMCP Display)
The EMCP display can be used to fine-tune the generator output voltage. Each press of the voltage raise or voltage lower key raises or lowers the voltage by 0.2% of rated voltage. When the voltage raise or voltage lower key is pressed and held continuously, the voltage bias is raised or lowered by 0.2% of rated approximately every 400ms.The "Voltage / Hz" screen can be found on the EMCP display. Use the following steps to navigate to the "Voltage / Hz" screen.
Press the "MAIN MENU" button on the EMCP.
Use the arrow keys to select "CONTROL". Press the "OK" key.
Use the arrow keys to select "VOLTAGE / Hz CONTROL". Press the "OK" key.
Illustration 13 g03488436
EMCP 4.3 and EMCP 4.4 Volts/Hz control screen
SCADA MODBUS (EMCP 4.4 ONLY)
EMCP 4.4 SCADA data link also provides a means for adjusting voltage remotely. EMCP 4.4 Modbus registers are defined for reading and controlling the target output voltage of the generator. Refer to Application and Installation Guide, LEBE0010, "EMCP 4 SCADA Data Links" for more details on EMCP 4.4 dedicated SCADA data links.Analog Inputs
Analog voltage adjustment is done via a programmable analog input to the EMCP configured for