DayTronic 3000PLUS Instrukcja obsługi - Strona 6

Przeglądaj online lub pobierz pdf Instrukcja obsługi dla Przyrządy pomiarowe DayTronic 3000PLUS. DayTronic 3000PLUS 20 stron. Panel meter, frequency conditioner module
Również dla DayTronic 3000PLUS: Instrukcja obsługi (20 strony)

Drukuj stronę

cially noisy. Responding only to the modulated carrier

frequency, the module rejects extraneous voltages that

can cause errors in DC systems, particularly when

there is a need to "blow up" a portion of the transducer

range.

The conditioner's advanced analog design directly

addresses the problem of measurement inaccuracy in

industrial environments of high electromechanical

noise. Exceptional signal stability and accuracy over a

remarkably wide range of sensor inputs are achieved

through

• regulated, remotely sensed AC excitation

• precise linearity / symmetry correction and signal

phase adjustment via software commands

• high-stability amplification

• configurable low-pass active filtering

• "absolute" and "two-point" software-based

calibration

• effective signal isolation & ESD protection

Plugging into the rear of the 3000PLUS meter, the 5D78

connects directly to its source strain gage sensor via

simple screw-terminal pinout (see Fig. 3). High output

accuracy over a wide temperature range guarantees

repeatable sensor signal integrity. For steady indication

and smooth, dependable control action, the conditioner

provides a true average value of the measured variable,

even in the face of substantial dynamic content.

The 5D78 features

• Powerful user-selectable low-pass active filter-

ing for removal of unwanted high-frequency mea-

surement-signal components and the elimination of

aliasing errors

• High noise rejection, eliminating errors from com-

mon-mode pickup and ground-loop coupling, with

1500 VAC isolation between input and output termi-

nals and between I/O and power supply / communi-

cations terminals

* Employing a low-capacitance cable will minimize the effects on

overall offset and span. See note (**) on page 1.4.

3000PLUS

5D78 I

WITH

1. I

NTRODUCTION

• High ESD immunity and extensive EMI protec-

tion further assure data integrity in harsh industrial

environments

Because of normal cable loading effects, it is a practical

necessity to calibrate any AC TORQUE SENSOR/

CABLE/INSTRUMENT system after installation, using a

known input standard. The "ABSOLUTE" CALIBRATION

method described in Sections 3.B and 4.E will normally

yield a very good first approximation for a sensor/

cable/5D78 system (depending, of course, on actual

cable length and capacitance).* However, absolute cal-

ibration of a 3000PLUS with installed Model 5D78

should always be followed by a conventional "in place"

TWO-POINT (DEADWEIGHT) CALIBRATION, for opti-

mum data integrity.

To perform initial ABSOLUTE CALIBRATION, you need

only use the front-panel menu or configuration software

to specify the desired relationship between the mod-

ule's measured engineering units and its ±5-VDC out-

put, given the full-scale input range for which it is

currently set and the source transducer's known full-

scale rating and sensitivity. A zero offset term may also

be entered, expressed either in engineering units or

millivolts.

TWO-POINT (DEADWEIGHT) CALIBRATION requires

the application of two independently and accurately

known values of input loading ("ZERO" and "SPAN"), fol-

lowing the entry of a phase shift adjustment. Activation

of a user-supplied shunt calibration resistor is provided

(for either a positive or negative upscale reading) for

use in the two-point method, if desired. Internal sym-

metry trimming is available for negative-domain slope

adjustments of up to ±2% of full scale, along with both

positive and negative midscale linearity correction.

NSTRUCTION

ANUAL V

. SB.3

3KP78 - 1.2