Tektronix 5110, Instruction Manual

Page: 43 / 128

Section 4— 5110
MAINTENANCE
This section of the manual contains information on
preparation for use and reshipment, information for
performing preventive maintenance, troubleshooting, and
corrective maintenance for this
instrument.
PREPARATION
FOR
USE AND RESHIPMENT
The following information provides detailed installa­
tion and operating voltage instructions for the os­
cilloscope.
Do not defeat the grounding connection. Any in­
terruption of the grounding connection can create
an electric-shock hazard. Before making external
connections to this instrument, always ground the
instrument first by connecting the power-cord to a
proper mating power outlet.
The color coding of the cord conductors may be in
accordance with the following table.
DETAILED OPERATING POWER
INFORMATION
This instrument can be operated from either a 120-volt
or 240-volt nominal line-voitage source, 48 to 440 hertz. In
addition, three regulating ranges are provided for each
nominal line-voltage source.
Table 4-1
POWER CORD CONDUCTOR IDENTIFICATION
Conductor Color Alternate Color
Ungrounded (Line) Brown Black
Grounded (Neutral)
Blue White
Grounding (Earthing) Green-Yellow Green-Yellow
To prevent damage to the instrument, always check
the line-voltage information recorded on the rear
panel before applying power to the instrument.
Power Cord Information
WARNING
J
This instrument is intended to be operated from a
single-phase earth-referenced power source having
one current-carrying conductor (the Neutral Con­
ductor) near earth potential. Operation from power
sources where both current-carrying conductors
are live with respect to earth (such as phase-to-
phase on a three-wire system) is not recommended,
since only the Line Conductor has over-current
(fuse) protection within the instrument.
This instrument has a three-wire power cord with a
polarized two-pole, three-terminal plug for connec­
tion to the power source and safety-earth. The
safety-earth terminal of the plug is directly con­
nected to the instrument frame. For electric-shock
protection, insert this plug only in a mating outlet
with a safety-earth contact.
Line-Voltage and Regulating-Range Selection
This instrument can be operated from either a 120-volt
ora 240-volt nominal line-voltage source with power-line
frequencies of 48 to 440 hertz. In addition, three operating
ranges can be selected within each nominal line-voltage
source. This permits the oscilloscope transformer to
operate from 100-volt, 110-volt, 120-volt, 200-volt, 220-
volt, and 240-volt sources. The nominal voltage and
regulating range for which the instrument is currently set,
is marked on
the rear panel of the instrument. Before
connecting the oscilloscope to line-voltage power, always
check the rear panel to see if the voltage marked there
complies with the expected line-voltage usage. If the
voltage marked is proper, a change of line voltage or
regulating range will not be necessary.
To select a different operating range, use the following
procedure to obtain correct instrument operation from the
line voltage available:
1. Disconnect the instrument from the power source.
2. Remove the bottom cabinet panel of the instrument
(see Cabinet Removal in this section) to gain access to the
LV Power Supply circuit board.
4-1