DayTronic 3000 series, Instruction Manual

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Daytronic Corporation
A
out
@ f
0
= 0.7 A
in
A
out
@ 10 f
0
= 0.001 A
in
T = 1.4/f
0
where A
out
= output amplitude
A
in
= input amplitude
f
0
= selected cutoff frequency
T = time-to-answer in seconds (output of filter within 0.1%
of final value after step function is applied).
3. CALIBRATION
This section contains the instructions for calibrating the 3178. Included is a
functional description of the instrument front-panel (see Figure 5). To perform
calibration, proceed as follows.
Turn power ON by placing the rear-panel slide switch in the ON posi-
tion. The front-panel indicator should light to indicate the application of
ac power. Allow 5 minutes of warmup for stabilization of transducer
characteristics.
Set the
Fine
and
Coarse
SPAN controls fully clockwise.
With the transducer unloaded, press the NULL button and adjust the C
BALANCE control to obtain the minimum (least positive or most nega-
tive) output reading. In some instances, an integral digital indicator will be
used to display the conditioner output (Model 3278 or 3378). When only
the conditioner is supplied (3178), an external indicator must be used to
monitor the conditioner output.
Release the NULL button and bring the output reading to zero with the
Fine
and
Coarse
R balance controls.
Load the transducer in the positive direction with a convenient
dead weight
value which is greater than one half of full scale. Then remove the 3178's
front panel (one small flat-head screw near each edge) to access both the
SYMMETRY and PHASE adjustments. Adjust the PHASE control (the one
on the
extreme right),
until a
maximum output
value is obtained. Then replace
the front panel. (Once set for your transducer, this PHASE ADJUSTMENT
step need not be repeated unless a great change in cable length–or
capacitance–is required). Adjust the
Coarse
and
Fine
SPAN controls until
11
(b)
(a)
(c)
(d)
(e)