Cutler-Hammer EATON Ampgard Mark V Manual de instruções - Página 3

Procurar online ou descarregar pdf Manual de instruções para Controlador Cutler-Hammer EATON Ampgard Mark V. Cutler-Hammer EATON Ampgard Mark V 12 páginas. Solid-state, brush-type, synchronous motor controllers

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I.B. 48008

the field has not yet been energized by the DC power

supply, or the converse, the motor coasting to a stop with

the field deenergized.

The controller protective functions include:

1. Locked-rotor protection

2. Incomplete-sequence protection

3. Failure-to-synchronize protection

4. Loss-of-synchronization (pull-out) protection

5. Open-phase protection

6. DC loss (field loss) protection

Automatic power factor regulation is not included with the

standard unit, but is available as an option.

Functions

Mark V controllers for synchronous motors consist of the

basic components shown in Figure 4. Their functions are

as follows:

The line contactor (M) operates to connect the motor to

the AC line. Additional contactors are required in reduced-

voltage starters to short out the reactor or to connect and

disconnect the autotransformer in the circuit.

The overload protection relay (e.g., IQ1000-II) protects the

motor from damage by overcurrent conditions, single

phasing, or other abnormal conditions such as phase

reversal or ground fault. It operates to trip the line

contactor M.

The starting and field-discharge resistor (S/D RES) is

used to improve the motor starting torque and to limit the

induced field voltage during starting or when the field

excitation is removed. The resistor current and ohmic

values are determined by the motor designer. The motor

controller is designed to operate motors with less than

1,500 volts rms in the field during starting. The current

flowing to the resistor is controlled by diode D1 and SCR

Q4 (Fig. 4). Voltage feedback (VR on the synchronizing

control board) provides information about the induced field

voltage, frequency, and phase angle.

Effective 11/97

Fig. 2 Mark V Field Power Supply Panel

Fig. 3 Synchronizing Control Board

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