DT238: High DC Voltage Input Two-Wire Dual Transmitter

DT238: High DC Voltage Input Two-Wire Dual Transmitter Description

DT230 series signal conditioners provide two independent I/O channels in a single, space-saving unit. The DT238 model is a two-wire dual transmitter that isolates and converts high-level DC voltage inputs to proportional 4-20mA control signals. Power is received from the output loop current or a DC supply when using a three-wire connection.

High-voltage isolation separates all input and output circuits from each other. Isolation protects from surges, reduces noise, and eliminates ground loop errors.

Setup and calibration are fast and easy with a convenient USB connection to your PC and Acromag’s Windows configuration software. The Android app enables setup with mobile devices.

Advanced signal processing capabilities, variable range input/output, and convenient USB programming make this instrument very versatile. These transmitters can withstand harsh industrial environments and operate reliably across a wide temperature range with very low drift. They feature RFI, EMI, ESD, EFT, and surge protection plus low radiated emissions.

Performance Specifications

IMPORTANT: To prevent ground loop error between a grounded PC and a grounded input signal, Acromag strongly recommends use of a USB isolator like Acromag’s USB-Isolator when configuring a DT230 Series transmitter.

USB Interface

USB Connection
Type: USB Mini-B type socket, 5-pin.
Data Rate: 12Mbps. USB v1.1 and 2.0 compatible.
Maximum cable length: 5.0 meters.
Transient voltage suppression on power and data lines.

Input (two channels)

Default Configuration/Calibration:
Input: ±150V, medium filter.
Output: 4 to 20mA.

Scaling Adjust: Full range.

Input Impedance:
Path A: 15MΩ.
Path B: 1MΩ.

Input Over-Voltage Protection: Bipolar Transient Voltage Suppression (TVS) and diode clamping.

Input Filter: RC filter plus variable digital filter (none, low, medium, high).

Input Bandwidth: -3dB @ 16Hz (no filtering).

Noise Rejection (@ 60Hz, no filter):
Common Mode: 70dB no filter (113dB high filter).
Normal Mode: Path A 32dB, Path B 51dB no filter (>80dB high filter).

Output (two channels)

D/A Converters (DAC): Two 16-bit D/A converters.

Output Ranges: 4-20mA DC 3.5-24mA under/over-range capability.

Output Accuracy: ±0.05%, typical. ±0.1%, maximum.

Output Compliance:
Rload = (Vsupply – 7V) / 0.020A.
Rload = 0 to 850 ohms @ 24V DC.

Output Response Time (for step input change)

Time to reach 98% of output value (typical)
No filtering               34 milliseconds
Low filter                  62 milliseconds
Medium filter         195 milliseconds
High filter             1109 milliseconds

Output Ripple: Less than ±0.1% of output span.

Environmental

Operating temperature
Operation: -40 to 80°C (-40° to 176°F).

Storage: -40 to 85°C (-40 to 185°F).

Relative humidity: 5 to 95% non-condensing.

Power Requirement: Loop-powered, 7-32V DC SELV, 24mA max.

Isolation: 1500V AC peak. 250V AC (354V DC) continuous isolation between input and output circuits.

Shock and Vibration Immunity:
Vibration: 4g, per IEC 60068-2-6.
Shock: 25g, per IEC 60068-2-27.

Approvals 
CE compliant. Designed for UL/cUL Class I Division 2 Groups ABCD, ATEX / IECEx Zone 2, II 3 G Ex nA IIC T4 Gc -40°C < Ta < +80°C.

Electromagnetic Compatibility (EMC) Compliance
Radiated Emissions: BS EN 61000-6-4, CISPR 16.

RFI: BS EN 61000-6-2, IEC 61000-4-3.

Conducted RFI: BS EN 61000-6-2, IEC 61000-4-6.

ESD: BS EN 61000-6-2, IEC 61000-4-2.

EFT: BS EN 61000-6-2, IEC 61000-4-4
Surge Immunity: BS EN 61000-6-2, IEC.1000-4-5

Physical

General: General-purpose enclosure designed for mounting on 35mm “T-type” DIN rail.

Case Material: Self-extinguishing polyamide, UL94 V-0 rated.

I/O Connectors: Removable plug-in terminal blocks rated for 12A/250V; AWG #26-12, stranded or solid copper wire.

Dimensions: 17.5 x 114.5 x 99.0 mm (0.7 x 4.51 x 3.90 inches).

Unit weight: 0.16 kg (0.35 pounds).

Shipping Weight: 0.22 kg (0.5 pounds) packed.

Additional information