Basler Electric AEC63-7 Voltage Regulator

INTRODUCTION

The AEC63-7 voltage regulator is designed for use on low

voltage, 50/60 Hz brushless generators. Regulator

features include frequency compensation, overexcitation

detection and output, a solid-state buildup circuit, and

internal noise suppression.

FUNCTIONAL DESCRIPTION

Frequency Compensation

The frequency compensation characteristic of Figure 1 is

used to improve system load pickup performance by

restraining voltage recovery until frequency has also

started to recover. The regulator is shipped from the

factory set at a 47-Hz corner frequency for 50 Hz systems.

For 60 Hz systems, a 57-Hz corner frequency is achieved

by moving the jumper wire from the 50 and HZ terminals

to the 60 and HZ terminals.

Overexcitation Time Delay

If the regulator output voltage exceeds 65 Vdc ±2 Vdc, the

regulator automatically makes a connection across

terminals A1 and A2 via an optically-isolated triac device.

This occurs after a time delay which is inversely

proportional to the magnitude of the regulator output

overvoltage condition up to approximately 105 Vdc ±5 Vdc

(see Figure 2). Beyond this point, the field voltage is

removed at a much faster rate. To avoid tripping due to

the voltage provided by a separate current boost circuit,

voltage measurement excludes any additional boost

voltage term. The overexcitation circuit is reset by

reducing the regulator input voltage to less than its buildup

value for 5 seconds.

This feature is designed to protect the generator and

regulator by allowing disconnection of the overloaded

part(s) of the system. Should the regulator be allowed to

run in excess of its rated current for any extended period

of time after the protection output closes, failure of the

recommended supply fuse will occur, but regulator

damage may also take place.

Overexcitation Shutdown

Overexcitation detection provides a single-pole solid-state

contact closure across terminals A1 and A2. should the

regulator output voltage exceed 65 Vdc ±2 Vdc for a

sufficient time. For voltage above 105 Vdc ±5 Vdc, there is

a second (shorter) inverse time curve. The total inverse

time delay curve is shown in Figure 2.

After the overexcitation solid-state contact has been

made, the regulator overexcitation circuit can be reset by

decreasing the supply voltage on terminals 3 and 4 to less

than 6 Vac for a minimum of 2 seconds. This may be

accomplished by stopping the prime mover or interrupting

the regulator input by means of a reset switch. In cases

where the generator is operating in parallel mode, it may

not be desirable to allow the regulator alone to shut down

which may cause the generator to be motored. However,

continuous operation at output currents greater than the

continuous rating after the overexcitation contact has been

made may result in failure of the ac supply fuse or may

eventually cause regulator failure. If this kind of operation

will take place, an alternative external means should be

employed to protect the system.

A1 and A2 are optically isolated and floating. Any supply,

12 to 250 Vac or dc may be used, provided that current is

limited to 150 mA. Use of a dc supply to terminals A1 and

A2 will cause the solid-state device to latch after tripping.

In this case, the supply must also be removed to unlatch

the device.

Current Boost Logic

The Current Boost Logic, provided at terminals CB+ and

CB–, allows the regulator to enable and disable an

external Current Boost System. The interface is designed

to operate with Basler Current Boost models CBS305 and

CBS212A.

If the sensing voltage drops about 10% below the voltage

setpoint, then the Current Boost Logic will enable the

Current Boost System. Once the sensing voltage

increases to about 5% below the voltage setpoint, the

Current Boost System will be disabled.

When the Current Boost interface is not required, then no

connections should be made at terminals CB+ and CB–.