Impulse DSCA45 - Manual

High Performance Signal Conditioners DSCA
For information call 800-444-7644 152
DSCA45
Frequency Input Signal Conditioners
Description
Each DSCA45 frequency input module provides a single channel of frequency
input which is isolated and converted to a standard analog voltage or current
output (Figure 1).
The frequency input signal can be a TTL level or zero-crossing signal. Terminal
7 (-IN) on the field-side terminal block is the “common” or ground connection
for input signals. A TTL signal is connected from terminal 6 (+IN) to terminal 7
(-IN), while a zero-crossing signal is connected from terminal 5 (+EXC) to
terminal 7 (-IN). Input circuitry for each of the signal types has hysteresis built
in. An input signal must cross entirely through the hysteresis region in order to
trigger the threshold comparator.
A +5.1V excitation is available for use with magnetic pick-up or contact-closure
type sensors. The excitation is available on terminal 8 (-EXC) with return at
terminal 7 (-IN).
Module output is either voltage or current. For current output models a dedicated
loop supply is provided at terminal 3 (+OUT) with loop return located at terminal
4 (-OUT). The system-side load may be either floating or grounded.
Special input circuits provide protection against accidental connection of power-
line voltages up to 480VAC and against transient events as defined by ANSI/
IEEE C37.90.1. Protection circuits are also present on the signal output and
power input terminals to guard against transient events and power reversal.
Signal and power lines are secured to the module using screw terminals which
are pluggable terminal blocks for ease of system assembly and reconfiguration.
DSCA45 modules have excellent stability over time and do not require
recalibration, however, both zero and span settings are adjustable to accom-
Figure 1: DSCA45 Block Diagram
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Features
• Accepts Frequency Inputs of 0 to 100kHz
• Industry Standard Output of Either 0-10V,
0-20mA, or 4-20mA
• ±0.05% Factory Calibrated Accuracy
• Adjustable Zero (±5%) and Span (±5%)
• 1500Vrms Transformer Isolation
• Input Overload Protected to 240VAC
Continuous
• ANSI/IEEE C37.90.1 Transient Protection
• Mounts on Standard DIN Rail
• C-UL-US Listed
• CE and ATEX Compliant
modate situations where fine tuning is desired. The adjustments are made using
potentiometers located under the front panel label and are non-interactive for
ease of use.