Impulse DSCA42 User Manual

High Performance Signal Conditioners

DSCA42

2-Wire Transmitter Interface Signal Conditioners With Loop Power

Description

Each DSCA42 2-wire transmitter interface module provides a single channel

of 4 to 20mA process current input which is filtered, isolated, amplified, and

converted to a high level voltage output. An isolated 24V power supply is

provided to power the 2-wire transmitter. Signal filtering is accomplished with

a five-pole filter which is optimized for step response. An anti-aliasing pole is

located on the field side of the isolation barrier, and the other four poles are on

the system side. After the initial field-side filtering, the input signal is chopped by

a proprietary chopper circuit. Isolation is provided by transformer coupling,

again using a proprietary technique to suppress transmission of common mode

spikes or surges.

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 240VAC 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 in pluggable terminal blocks for ease of system assembly and reconfiguration.

The modules have excellent stability over time and do not require recalibration,

however, zero and span settings are adjustable up to ±5% to accommodate

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.

▲

Features

 Accepts Process Loop Signals

 Industry Standard Output of either

0-10V, 2-10V, 0-20mA, or 4-20mA

 Provides Isolated Loop Excitation

 1500Vrms Transformer Isolation

 ANSI/IEEE C37.90.1 Transient Protection

 Input Protection to 240VAC Continuous

 True 3-Way Isolation

 Wide Range of Supply Voltage

 105dB CMR

 5 Poles of Filtering

 ±0.03% Accuracy

 ±0.01% Linearity

 Easily Mounts on Standard DIN Rail

 C-UL-US Listed

 CE and ATEX Compliant

DSCA

Figure 1: DSCA42 Block Diagram

148

For information call 800-444-7644

High Performance Signal Conditioners

DSCA

Specifications

Typical at T

= +25°C and +24V voltage supply

Module DSCA42

Input Range 4-20mA

Input Resistance

Normal <100Ω Power Off <100Ω Overload 65kΩ

Input Protection

Continuous 240Vrms max

Transient ANSI/IEEE C37.90.1

Loop Supply Voltage +20VDC

Isolated Excitation Protection

Continuous 240Vrms max

Transient ANSI/IEEE C37.90.1

Output Range See Ordering Information

Load Resistance (I

Current Limit 8mA (V

Output Protection

Short to Ground Continuous

Transient ANSI/IEEE C37.90.1

CMV, Input to Output, Input to Power

Continuous 1500Vrms max

Transient ANSI/IEEE C37.90.1

CMV, Output to Power

Continuous 50VDC max

CMR (50Hz or 60Hz) 105dB

(1)

Accuracy

Nonlinearity ±0.01% Span

Adjustability ±5% Zero and Span

Stability

Offset ±6ppm/°C (V

Gain ±40ppm/°C

Output Noise, 100kHz Bandwidth 500µVrms (V

Bandwidth, 3dB 100Hz

NMR (-3dB at 100Hz) 100dB/Decade Above 100Hz

Response Time, 90% Span 5ms

Power Supply

Voltage 19 to 29VDC

Current 60mA (V

Sensitivity ±0.0002%/%

Protection

Reverse Polarity Continuous

Transient ANSI/IEEE C37.90.1

Environmental

Operating Temp. Range 40°C to +80°C

ATEX Group II, Category 3 20°C to +40°C

Storage Temp. Range 40°C to +80°C

Relative Humidity 0 to 95% Noncondensing

Emissions EN61000-6-4 ISM, Group 1

Radiated, Conducted Class A

Immunity EN61000-6-2 ISM, Group 1

R F Performance A ±0.05% Span Error

ESD, EFT, Surge, Voltage Dips Performance B

Mechanical Dimensions 2.95" x 0.89" x 4.13"

(h)(w)(d) (75mm x 22.5mm x 105mm)

Mounting DIN EN 50022 -35x7.5 or -35x15 rail

NOTES:

(1) Includes nonlinearity, hysteresis and repeatability.

) 600Ω max

OUT

±0.03% Span

OUT

), 30mA (I

), ±20ppm/°C (I

), 2µArms (I

OUT

), 80mA (I

OUT

Ordering Information

Model Input Range Output Range

DSCA42-01 4mA to 20mA 0V to +10V

DSCA42-02 4mA to 20mA 2V to +10V

DSCA42-01C 4mA to 20mA 4 to 20mA

DSCA42-01E 4mA to 20mA 0 to 20mA

)

OUT

)

OUT

)

DSCA

Installation Notes:

1.) This Equipment is Suitable for Use in Class I, Division 2, Groups A, B, C, D, or Non-Hazardous Locations Only.

2.) Warning - Explosion Hazard - Substitution of Components May Impair Suitability for Class I, Division 2.

3.) Warning - Explosion Hazard - Do Not Disconnect Equipment Unless Power Has Been Switched Off or The

Area is Known to be Non-Hazardous.

Visit our website www.dataforth.com

149