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ELECTRONIC MANUAL VOLTAGE CONTROL
Model: MVC 300
Part Number: 9 1210 00 106
Publication Number: 9 1210 00 993
Date: July, 1993
Revision F: July, 1996
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WARNING
To prevent personal injury or equipment damage, only
qualified technicians/operators should install, operate, or
service this device.
CAUTION
Meggers and high potential test equipment should be
used with extreme care. Incorrect use of such equipment
could damage components contained in the device.
Rev ECA
E 15588
F 15760
CONFIDENTIAL INFORMATION
of Basler Electric Company, Highland, IL. It is loaned for
confidential use. Subject to return on request and with the
mutual understanding that it will not be used in any manner
detrimental to the interests of Basler Electric Company.
It is not the intention of this manual to cover all details and
variations in equipment, nor does it provide data for every
possible contingency regarding installation or operation. The
availability and design of all features and options are subject
to change without notice. Should further information be
required, call Basler Electric Company, Highland, IL.
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1-1. PURPOSE
The Electronic Manual Voltage Control (MVC-300) is used as a back-up control device to provide
manual voltage control in case of voltage regulator failure. The unit can be mounted on a control
panel in ground vehicles, stationary equipment or shipboard locations.
1-2. OVERALL DESCRIPTION
The MVC-300 is a solid-state device enclosed in a metallic dark grey chassis and designed to be
'through-the-panel' mounted with controls accessible to an operator from the front of the panel. A
terminal strip located on the rear of the device facilitates installation and operation. A MANUAL
VOLTAGE ADJUST control and an AUTO-OFF-MANUAL voltage control mode switch are provided on the front panel.
1-3. SPECIFICATIONS
Table 1-1 provides the electrical and physical specifications of the MVC 300.
Table 1-1. Specifications.
SECTION 1
GENERAL INFORMATION
Input Power:
Output Adjustment
Range:
120 Vac Input:
240 Vac Input:
Watts Dissipated: 30 W maximum.
Minimum Residual
Voltage for Buildup:
Ambient Operating
Temperature:
Ambient Storage
Temperature:
Shock Withstands up to 15 G's in each of three mutually perpendicular axes.
Vibration: Withstands the following:
Weight: 3.0 lbs. (1.36 kg) net, 5 lbs. (2.26 kg) shipping.
120 Vac, + 10%Single-Phase, 50-320 Hz.
240 Vac, + 10%Single-Phase, 50-320 Hz.
1 to 32 Vdc or 1 to 63 Vdc.
1 to 63 Vdc or 1 to 125 Vdc.
6 Vac.
-40 °F (-40 °C) to +158 °F (+70 °C)
-85 °F (-65 °C) to +212 °F (+100 °C)
5 - 27 Hz @ 1.3 G's,
27 - 52 Hz @ 0.036" double amplitude,
52 - 500 Hz @ 5 G's.
1-1
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2-1. GENERAL
a. The Electronic Manual Voltage Control (MVC-300) is a phase-controlled, silicon-controlled,
rectifier (SCR) bridge. By adjusting the front panel MANUAL VOLTAGE ADJUST control, the firing
angle of the SCR change providing an adjustable voltage level to the exciter field.
b. During start-up, the build-up circuit holds the SCRs power bridge at maximum output. When the
voltage has built-up to approximately 30 Vac, the internal build-up circuit relinquishes control to the
MANUAL VOLTAGE ADJUST control on the front panel.
c. The AUTO-OFF-MAN voltage control mode switch allows transfer from the voltage regulator to
the Manual Voltage Control or from Manual Voltage Control to voltage regulator. A free wheeling
diode remains connected to the field to allow safe switching without arcing.
d. The MVC-300 is designed to operate from 120 or 240 Volt nominal sources without any electrical
changes such as tap selection or terminal connections. Taps are provided to select 32, 63, or 125
volt maximum outputs.
SECTION 2
PRINCIPLES OF OPERATION
2-1