Datawell BV Hippy 40-MkII, Руководство пользователя

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Repair and pcb check 12.3
12.3.1 Repair
A procedure is given to determine whether the electronics is defective in case of faults.
If the cause is outside the electronics repair is only possible at Datawell generally.
No procedure is given to determine the fault on the print.
If the print is defective, the pcb should be replaced as a whole.
All indicated measurements are with regard to "common" unless otherwise stated.
Connected to common are: point 7 of junction box, brown leads to octal plug and all tabs
marked "
⊥ " on pcb.
Excessive zero offset (pitch-roll), (for calibration see 10).
Connect the pitch output to x input of an xy recorder.
Connect the rolloutput to y input of an xy recorder.
Sensitivity 100 mV/cm.
Lift the Hippy gently from the ground with two men and rotate it 360° in approx. 10 seconds
around vertical axis and replace on ground again.
Let the xy recorder write from now on for approx. 20 minutes.
You will observe that the xy recorder writes a nearby circle-like figure.
The radius of this circle is a measure for the platform offset.
For example: If radius of circle
: 2 cm
Sensitivity of xy recorder : 100 mV/cm
Sensitivity of Piro : 174 mV/°
Platform offset : 2x100/174 = 1.15°
If no xy recorder is available, write pitch and roll output on x, t recorder for 20 minutes after
rotation or measure and note pitch and roll output every 30 seconds.
Pitch and roll can be plotted on graphic paper now.
If the excessive zero offset is caused mainly by a platform offset, the instrument should be
returned to Datawell for repair.
If the zero offset is much larger than the platform offset, the cause may be in the electronics
circuit board.
Check the humidity (see 12.2).
If the humidity was too large, dry out silicagel and measure again.
If still too large check the print according to 12.3.2.
Sensitivity error, (for calibration see 9.2 and 10).
If sensitivity is much too small, check the connection supply-junction box and junction box-
indicating meter.
Check if the loading resistance of the outputs is not smaller than 4 KOhm.
The power drain should be approx. 150 Mw (measure at least 1 minute after energising).
Check if octal plug under lid is connected properly and brown lead is plugged on screen and
check connection octal plug-pcb.
If everything is in order proceed according to 12.3.2.