Marconi LORAIN RHM800E50, Руководство пользователя

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ing signal is missing or the control and alarm
card A? should be replaced.
DANGER
This procedure performed with power
applied to
the Hazardous AC volt-
ages capable of severe, perhaps
fatal
shock an? present at
the cabinet.
and
at Exercise caution
accidental not made
exposed electrical or with test
equipment cabinets while rectifier is
Place the POWER to the OFF posi-
tion Do not disconnect AC or DC power
sources.
Remove the lower front panel from the recti-
fier to gain access to
and power transformer
Locate the
firing cards, Part No. 4334-616-66. on
each assembly.
Adjust the vertical of an
scope for 5 per centimeter
Adjust horizontal base for 2 millisec-
onds per (2
DANGER
per-
forming this otherwise, to
personnel
shock
exists since
the
and case
of
test
equipment becomes to the
must exercise that
c h a s s i s o r
object when the test equipment is to
the
it
d) Open the meter and control panels by loos-
ening the captive fasteners.
Remove the edge connector one of the
firing cards. Connect the oscilloscope
to contact pin 5 the edge connector.
Connect the oscilloscope lead to
3 of any phase on
Section 4387
Start the rectifier by operating the POWER
to the ON position.
the displayed on the
oscilloscope. The waveform be simi-
lar to that shown in Figure 7-2. Amplitude
should be approximately 12 volts peak-to-
peek with a variable time duration depen-
dent upon AC input voltage and output
age settling. The waveform illustrated was
taken
the operating at 206 VAC
input and 52 VDC output 50% load.
h) After noting the firing waveform characteris-
tics, place the POWER switch to the OFF
position. Disconnect the oscilloscope
and replace
edge connector on
thyristor firing card.
Repeat Steps e) through for each remain-
ing firing circuit card input. If the waveshape
at any input edge connector is missing or
abnormal.
Regulator and cir-
cuit card A7.
When all tests are completed and any nec-
essary repairs accomplished, perform the
following steps:
Completely disconnect all test
ment leads
rectifier.
the fmnt panel on the
and secure it place with the
hardware originally used.
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