Basler Electric XR2002 and XR2002F PMG Voltage Regulator

GENERAL DESCRIPTION

The Basler XR2002 and XR2002F PMG Voltage Regulators provide the dc exciter field

regulation to PMG (Permanent Magnet Generator) equipped 50 or 60 Hz brushless generators.

The Regulator is available in two models:

XR2002: Standard (without a Voltage Limited Volts-per-Hertz characteristic).

XR2002F: With a Voltage Limited Volts-per-Hertz characteristic.

b. Input power may be provided by either a single-phase or a three-phase PMG, or optionally, it

may be supplied by the generator output.

FREQUENCY COMPENSATION

The XR2002F (only) provides the following types of frequency compensation:

a. Volts-per-Hertz (V/Hz). This is a linear relationship between voltage and frequency and is

shown in Figure 1-1. This characteristic is generally used to improve system block load pick-up

performance by restraining the voltage recovery until the frequency has also started to recover.

A front panel UF ADJ control is used in conjunction with a VOLT control to provide adjustment of

the V/Hz characteristic along both the frequency axis (45 to 65 Hz) and the generator axis of

Figure 1-1. This characteristic factory preset at 55 Hz (60 Hz nominal).

b. Voltage Limited Volts-per-Hertz (VLV/Hz). This characteristic provides the advantage of

the Volts-per-Hertz characteristic during load application as well as allowing precise voltage

regulation during minor variations in generator speed. The "60 Hz" and "50 Hz" curves of Figure

1-1 represent the 60 Hz and 50 Hz VLV/Hz characteristic. The front panel UF ADJ control

provides adjustment of the corner frequency of both VLV/Hz characteristics along the frequency

axis of Figure 1-1.

VOLTAGE ADJUST CONTROL

a. An internal VOLT screwdriver adjust provides adjustment of the generator output voltage.

Clockwise rotation of this control will increase the generator output voltage.

b. The voltage regulator is shipped from the factory with a jumper connected across terminals 6

and 7. If a remote voltage adjust rheostat (R50) is used (supplied loose), the jumper across

these terminals should be removed and the remote voltage adjust rheostat should be connected

to these terminals. The wiper of the rheostat must be connected to the rheostat terminal which

connects to terminal 6 of the voltage regulator and the other terminals are connected as shown in

the interconnection diagram.

c. When the remote voltage adjust rheostat is adjusted to its maximum resistance (fully counter

clockwise), the minimum generator output voltage will be obtained. Also, when the remote

voltage adjust rheostat is use, the front panel VOLT control will operate as a voltage range adjust

control.

TERMINALS 51.52.53. 54. AND 55 (and 56 on units S/N 1 through 236)

a. These terminals allow additional external accessories and modules to be combined with the

voltage regulator to expand the capabilities of the regulator. An internal jumper must be

connected to terminal 54 for normal regulator operation. An external jumper is normally

connected between terminals 53 and F+. This jumper may be replaced by an excitation

shutdown switch. No connection should be mad to terminals 51. 52. 55. or 56 unless so directed

by an accessory device instruction manual. Refer to Paragraph 2-5.

b. Note that on units with serial numbers 001 through 236. terminal 56 is used in lieu of terminal

55. On units with serial numbers 237 and higher, terminal 56 is not present and terminal 55 is

used for the external connections.