User's Manual

AT71-250 Transmitter Owner’s Manual

The 4810 module is an AC / DC converter having power factor correction (PFC) with input of 180VAC

to 240VAC and 370VDC output referenced to AC mains ground (not isolated).

The configuration used by this converter topology is named Boost Regulator. This configuration uses

one MOSFET, one diode, one coil operation under a 100 KHz switching frequency.

This circuit also includes an in rush starting section composed by one relay and thermistors, the

function of this circuit is to reduce the start rush current. The in rush circuit control is assemble in a

separate printed circuit board, CIP 8673.

The module consists of the following boards:

- Power Plate (PFC): CIM 3869 and CIP 8709

- Control Board (PFC): CIM 3825 and CIP 8673

MOD 4810 Technical Specifications:

Parameter

Specification

Input Voltage

180Vac to 240Vac

Switching Frequency

100 KHz

Nominal Output Voltage

370 Vdc

Nominal Power

2kW

Max Current

5.5A

MOD CIM 3747 and MOD CIM 3779: Control Board and Inter-connections Board

The main digital control unit board is named CIP 8609. This board digitally manages the control

functions of the drawer GV 4790. When used as a Digital-On-Channel-Repeater (Gap-filler) or as a

simple repeater, the GV 4790 will be programmed via the RS485 protocol between the control-exciter

unit and the drawer itself. The end user can produce set of configurations (program) into the drawer

also using the USB port connected to a PC with Hyperterminal.

The modules that execute the digital controls are;

MOD CIM 3779: dedicated to connections

MOD CIM 3747: the control itself.

Together they perform the following functions:

a. Communication with the external control unit module via RS-485.

b. Hyper-terminal measurements and configurations via USB port.

c. Digital and Analog measurements readings.

d. Adjustments for the idle currents over the RF power transistors.

e. Automatic stabilization of the idle currents on the RF power transistors.

f. Automatic fan speed control.

g. Checking alarms.