Impulse DSCA38 User Manual

DSCA38

Strain Gage Input Signal Conditioners

Description

Each DSCA38 strain gage input module provides a single channel of strain gage

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

output. 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.

The DSCA38 can interface to transducers with a nominal resistance of 100

to 10kΩ. Strain gage excitation is provided from the module by a stable 10V or

3.333V source. This source is fully isolated, allowing the amplifier inputs to

operate over the full range of the excitation voltage. This feature enables the

module to be interfaced to other sensors requiring exctitation.

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 signal input and excitation 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

High Performance Signal Conditioners

DSCA

▲

Features

 Interfaces to 100Ω through 10kΩ Strain Gages

 Industry Standard Output of either ±10V,

0-20mA, or 4-20mA

 1500Vrms Transformer Isolation

 ANSI/IEEE C37.90.1 Transient Protection

Ω

situations where fine-tuning is desired. The zero adjustment can be used to offset

bridge imbalances. The adjustments are made using potentiometers located

under the front panel label and are non-interactive for ease of use.

 Input Protected to 240VAC Continuous

 True 3-Way Isolation

 Wide Range of Supply Voltage

 100dB CMR

 Fully Isolated Excitation Supply

 ±0.03% Accuracy

 ±0.01% Linearity

 Easily Mounts on Standard DIN Rail

 C-UL-US Listed

 CE and ATEX Compliant

Figure 1: DSCA38 Block Diagram

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For information call 800-444-7644

High Performance Signal Conditioners

DSCA

Specifications

Module

Input Range ±10mV to ±100mV

Input Bias Current ±0.5nA

Input Resistance

Normal 50MΩ
Power Off 65kΩ
Overload 65kΩ

Signal Input Protection

Continuous 240Vrms max (Full Bridge)

Transient ANSI/IEEE C37.90.1

Excitation

Output 10V ±0.03% or 3.33V ±0.03%

Load Resistance (10V) 300Ω to 10kΩ
Load Resistance (3.33V) 100Ω to 10kΩ

Load Regulation ±5ppm/mA

Stability ±15ppm/°C

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) 100dB

(1)

Accuracy

Nonlinearity ±0.01% Span

Adjustability ±5% Zero and Span

Stability

Input Offset ±1µV/°C

Output Offset ±6ppm/°C (V

Gain ±55ppm/°C

Output Noise, 100kHz Bandwidth 750µVrms (V

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

DSCA38

120Vrms max (Half Bridge)

) 600Ω max

OUT

OUT

±0.03% Span

OUT

OUT

), 30mA (I

), ±20ppm/°C (I

), 3µArms (I

OUT

Ordering Information

Input

Bridge

Model

Type

Input Range

Excitation Sens.

DSCA38-01 Full -10mV to +10mV +3.333V 3mV/V 1

DSCA38-02 Full -30mV to +30mV +10.0V 3mV/V 1

DSCA38-03 Half -10mV to +10mV +3.333V 3mV/V 1

DSCA38-04 Half -30mV to +30mV +10.0V 3mV/V 1

DSCA38-05 Full -20mV to +20mV +10.0V 2mV/V 1

DSCA38-06 Full -33.3mV to +33.3mV +3.333V 10mV/V 1

DSCA38-07 Full -100mV to +100mV +10.0V 10mV/V 1

DSCA38-08 Full -10mV to +10mV +3.333V 3mV/V 2, 3, 4

DSCA38-09 Full -30mV to +30mV +10.0V 3mV/V 2, 3, 4

DSCA38-10 Half -10mV to +10mV +3.333V 3mV/V 2, 3, 4

DSCA38-11 Half -30mV to +30mV +10.0V 3mV/V 2, 3, 4

DSCA38-12 Full -20mV to +20mV +10.0V 2mV/V 2, 3, 4

DSCA38-13 Full -33.3mV to +33.3mV +3.333V 10mV/V 2, 3, 4

DSCA38-14 Full -100mV to +100mV +10.0V 10mV/V 2, 3, 4

DSCA38-15 Full 0 to +10mV +3.333V 3mV/V 2, 3, 4

DSCA38-16 Full 0 to +30mV +10.0V 3mV/V 2, 3, 4

)

DSCA38-17 Half 0 to +10mV +3.333V 3mV/V 2, 3, 4

DSCA38-18 Half 0 to +30mV +10.0V 3mV/V 2, 3, 4

DSCA38-19 Full 0 to +20mV +10.0V 2mV/V 2, 3, 4

DSCA38-20 Full 0 to +33.3mV +3.333V 10mV/V 2, 3, 4

DSCA38-21 Full 0 to +100mV +10.0V 10mV/V 2, 3, 4







Output Ranges Available

Output Range Part No. Suffix Example

1. -10V to +10V NONE DSCA38-01

2. 0V to +10V NONE DSCA38-08

3. 4 to 20mA C DSCA38-08C

)

4. 0 to 20mA E DSCA38-08E

OUT

OUT

)

Output

Range



DSCA

Bandwidth, 3dB 3kHz

NMR 100dB/Decade Above 3kHz

Response Time, 90% Span 170µs

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.

), 80mA (I

OUT

Visit our website www.dataforth.com

OUT

)

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.

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