Impulse DSCA36 User Manual

DSCA36

Potentiometer Input Signal Conditioners

Description

Each DSCA36 potentiometer input module provides a single channel of

potentiometer input which is filtered, isolated, amplified, and converted to a high

level voltage output. Signal filtering is accomplished with a five-pole filter which

provides 85dB of normal-mode-rejection at 60Hz and 80dB at 50Hz. 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.

Potentiometer excitation is provided from the module using a precision current

source. Lead compensation is achieved by matching two current paths which

cancels the effects of lead resistance. The excitation current is small (approx.

0.25mA) which minimizes self-heating of the sensor.

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.

High Performance Signal Conditioners

▲

Features

 Interfaces to Potentiometers up to 10kΩ

 Industry Standard Output of Either 0-10V,

0-20mA, or 4-20mA

 1500Vrms Transformer Isolation

 ANSI/IEEE C37.90.1 Transient Protection

 Input Protected to 240VAC Continuous

 True 3-Way Isolation

 Wide Range of Supply Voltage

 160dB CMR

 85dB NMR at 60Hz, 80dB at 50Hz

 ±0.03% Accuracy

 ±0.01% Linearity

 Easily Mounts on Standard DIN Rail

 C-UL-US Listed

 CE and ATEX Compliant

DSCA

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.

Figure 1: DSCA36 Block Diagram

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For information call 800-444-7644

High Performance Signal Conditioners

DSCA

Specifications

Module

Typical at TA=+25°C and +24V supply voltage

DSCA36

Input Range Limits 0Ω to 10kΩ

Input Protection

Continuous 240Vrms max

Transient ANSI/IEEE C37.90.1

Sensor Excitation Current 260µA; 100Ω, 500Ω, 1kΩ Sensor

65µA; 10kΩ Sensor

Lead Resistance Effect ±0.01Ω/Ω; 100Ω, 500Ω, 1kΩ Sensor

±0.02Ω/Ω; 10kΩ Sensor

Output Range See Ordering Information

Load Resistance (I

Current Limit 8mA (V

Output Protection

) 600Ω max

OUT

), 30mA(I

OUT

)

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) 160dB

(1)

Accuracy

±0.03%

Conformity ±0.01%

Adjustability ±5% Zero and Span

Stability

Input Offset ±0.004Ω/°C; 100Ω, 500Ω, 1kΩ Sensor

±0.01Ω/°C; 10kΩ Sensor

Output Offset ±6ppm/°C (V

Gain ±60ppm/°C

Output Noise, 100kHz Bandwidth 250µVrms (V

), ±20ppm/°C (I

OUT

), 1µArms (I

OUT

)

Bandwidth, 3dB 3Hz

NMR 85dB at 60Hz, 80dB at 50Hz

Response Time, 90% Span 250ms

Open Input Response

+ Lead Upscale

 Lead Non-deterministic

x Lead Downscale

Power Supply

Voltage 15 to 30VDC

Current 25mA (V

Sensitivity ±0.0001%/%

), 55mA (I

OUT

)

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.

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.

Ordering Information

Model Input Range Output Range

DSCA36-01 0 to 100Ω 2, 3, 4 DSCA36-02 0 to 500Ω 2, 3, 4 DSCA36-03 0 to 1kΩ 2, 3, 4 DSCA36-04 0 to 10kΩ 2, 3, 4







Output Ranges Available

Output Range Part No. Suffix Example

1. -10V to +10V NONE NA

2. 0V to +10V NONE DSCA36-01

3. 4 to 20mA C DSCA36-01C

4. 0 to 20mA E DSCA36-01E



DSCA

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