HBM ME30, Operating Manual

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12
ME 30
3 Putting into Operation
If the factory settings, such as the measuring range or zero balance are re-
tained, the operation is limited to setting the zero point and the measuring
ranges.
3.1 Select Measuring Range
With the factory setting
measuring range 1
(
±
2mV/V) is always switched on.
Measuring range 2 (calibration at
±
0.2mV/V) can be selected either internally
via DIP switch 24/4 or externally by closing a single-pole change-over switch
to pin 25c against operating voltage zero (see chapter 4.2).
3.2 Bridge Zero Balancing
Carry out bridge zero balancing by means of the screwdriver potentiometers
P23 (fine) and switches S22 (coarse) and S23 (polarity). (See also chapter
4.4).
3.3 MR Fine Adjustment
The fine adjustment of the measuring range is made seperately for both
ranges by means of the screwdriver potentiometers P21 (measuring range 1)
and P22(measuring range 2). The potentiometers in the front panel permit
corrections of approx. 35% (related to the set measuring range). As far as
measuring range 1 is concerned, the fine adjustment is also possible via an
external potentiometer (for this see chapter 4.3).
Attention: P22 must not be altered in order not to detune the manufacturer’s
setting (MR2
±
0.2mV/V). (see chapter 4.5)