Bently Nevada 3300/48, Руководство по эксплуатации

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Case Expansion Monitor Maintenance
17171 Calibrate Channels [Cont]
4. Short calibration terminals (CA) using a clip lead
(a jumper may be used if the monitor is on an
extender card). A test pattern will appear on the
display when t h e Calibration terminals a r e
shorted and no Calibration switches are set.
Both Bypass lights will come on.
5. Manually adjust the core position until the Digital
Multimeter displays 0.00 Vdc.
6. Move the core of the LVDT as follows:
If t h e f u l l scale expansion i s toward t h e
transducer, then move the core away from the
transducer exactly half the full scale meter
range. The transducer output voltage should be
within the Zero range specified in Table 6 on
page 24.
If the full scale expansion i s away from the
transducer, then move the core toward t h e
transducer exactly half the full scale meter
range. The transducer output voltage should be
within the Zero range specified in Table 6 on
page 24.
7. Activate the channel A zero adjust dipswitch
(ZA) by moving it to the left.Measure the voltage
at Te s t Point channel A ( TA ) u s i n g t h e
multimeter. Press the MODE switch and use the
(r) and ( I ) switches o n the system card t o
adjust the voltage at TA to get
0.00 ± 0.03Vdc. Note the bypass light will
indicate an under-range adjustment by flashing
at a 5 Hz rate. If this happens back off the
adjustment until the correct voltage is achieved
and the bypass light is on steady.
8. De-activate the channel A zero adjust dipswitch
(ZA) b y moving it to the right. If the short is
removed from the Calibration terminals before
the dipswitch is deactivated, the adjustment will
not be stored.
CASE EXPANSION
MONITOR
84418-01
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