Tektronix 323, Инструкция по эксплуатации

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Maintenance— Type 323
Circuit Board. Components on the Battery Charger cir­
cuit board can be replaced without removing the board. To
reach the under-side of the board, remove the three nuts
which hold the board in place. Turn the Power Pack over
to permit the washers to fall free of the board.
CAUTION
Do not a llow components to become short circuited
while the battery pack is connected to the circuitry.
If a resistance check or disassembly is to be per­
formed, it is recommended that the battery lead
connected to terminal M o f the circuit board be
unsoldered and taped to avoid damage.
After the nuts and washers have been removed, the outer
end of the board can be lifted up, pivoting it on the wiring
cable. Be careful that the screw near the transformer does
not bind on the corner of the board. If the board must be
completely removed, the wire color code should be re­
corded before any wires are unsoldered.
Transformer. To remove the transformer, unsolder its
eight leads from the circuit board. Remove the Power Pack
cover plate from the opposite side by removing the six
screws from if. Then remove the two transformer mounting
bolts; the transformer can then be lifted out through the
hole in the side plate. See Fig. 4-10 for 115-230 V wiring
information.
Fuse. Access to the fuse can be obtained by pulling the
plastic cap off toward the bottom. When replacing it,
be sure that the grooves in the cap align with the fuse mount­
ing board. See Fig. 4-10 for 115-230 V fusing information.
Battery. The battery in the Power Pack is made up of
six 1.25V Nickel-Cadmium (NiCd) cells strapped together,
series-aiding. See Fig. 4-11. Background information re­
garding these cells is given in the Operating Instructions
section and should be read before any servicing is performed
on the battery.
Fig. 4 -1 0 . Connections fo r 115 V and 23 0 V AC operatio n. Place
insulated sleeves on unused square pins a fte r changing the con­
nections.
Battery Pack Removal. Unsolder the two leads which
connect the battery pack to terminals I and M on the circuit
board. Free the one lead from the cable clamp. Tape up
one lead end (creating minimum bulk) so that the two leads
cannot come in contact with each other. Remove the nine
screws and the cover plate from the power connector side
of the Power Pack. Remove the three battery pack screws
through the access holes in the circuit board, freeing the
pack. Separate the pack from the rest of the unit, pulling the
pack leads through the hole in the circuit board. The bat­
tery holding bracket now can be removed by removing
one screw from each end. The pack can be re-installed by
reversing the procedure.
Servicing the Battery. The cells which make up the bat­
tery have been selected to meet specific performance re­
quirements and can be expected to maintain relatively
equal capabilities throughout the battery operating life.
Upsetting this balance of equality by introducing a strong
cell into a weak battery, or a weak cell into a strong bat­
tery, will precipitate reverse charging of the weakest cells,
as explained in the Operating Instructions.
If one cell is defective and fails while the rest of the
battery is still quite new, that cell may be replaced without
undue concern. The Tektronix Field Representative or Office
should be consulted before individual cells are replaced,
especially if the warranty is in effect.
Gas evolution and recombination takes place during bat­
tery charging. This creates a pressure within the cells which
they normally can withstand. If a cell becomes defective,
or a circuit failure causes the recommended charge rate to be
exceeded, excessive pressure builds up. The pressure may
rupture a relief vent, exhausting the gas. This action may
shorten the life of the cell, and will coat the surrounding
areas with a corrosive substance.
Fig. 4 -1 1 . Battery w irin g .
4-12