DayTronic 3000 series, Instruction Manual

Page: 20 / 30

Daytronic Corporation
the output value equals the
dead weight
value. Remove the
dead weight,
and
then press the +CAL button, noting the indicator reading obtained. In future
calibrations, you need only press the +CAL button and adjust the SPAN
controls until you obtain the previously recorded
dead weight
reading.
If the transducer is to be also used in the negative realm, load the
transducer in the negative direction with the same
dead weight
value as
used in step (e) and confirm that the
dead weight
reading obtained is the
same as that of step (e). If not, see steps (g) thru (i).
An internal
Symmetry
adjustment is provided to compensate for trans-
ducers that do not have symmetrical sensitivity characteristics. This
adjustment is factory set assuming symmetrical characteristics. If step
(f) indicates that a field adjustment is necessary, proceed as follows.
Remove the front panel by removing the two 2-56 flat-head screws to
obtain access to the
Symmetry
adjustment.
With the transducer loaded as in step (f), adjust the
Symmetry
control (just
to the right of the –CAL button) to obtain a
dead weight
reading equal to
that obtained in step (e).
If
dead weight
calibration is not practical and the transducer manufac-
turer has supplied a calibration resistor (or resistor value), install the
recommended calibration resistor.
Repeat steps (b) thru (d). Now press the +CAL button and adjust the
SPAN controls until the instrument output is equal to the
Equivalent
Input
value simulated by the installed resistor.
If a negative
Equivalent Input
value is also provided (as in the case of
Lebow
1600 Series
transducers), press the –CAL pushbutton and con-
firm that the negative value can also be obtained with the same setting of
the
Coarse
and
Fine
SPAN controls. If not, adjust the
Symmetry
control
to obtain the negative
Equivalent Input
value.
If
dead weight
calibration is not practical and the transducer calibration
data is unknown, the
Equivalent Input
value for the factory-installed
calibration resistor can be approximated
mv/v sensitivity rating of the transducer
known.
as follows, assuming that
and the bridge resistance
the
are
13
(f)
(g)
(h)
(i)
(j)
(k)
(l)
(m)