Transmitter, Potentiometer/Thermistor Input, 12-32V DC Loop/Local/ Power
• Potentometer/slidewire: 100 to 100k ohms
•Thermistor: 0 to 100k ohms, -50 to 200°C
• 4 to 20mA DC
• 12-32V DC power
The TT234 model is a space-saving two-wire transmitter that isolates and converts a resistive sensor input to a proportional 4-20mA signal. Power is received from the output loop current or a DC supply when using a three-wire connection. The transmitter provides sensor excitation plus performs linearization, lead-wire compensation, and lead-break detection.
Setup and calibration are fast and easy with a convenient USB connection to your PC and Acromag’s Windows configuration software.
Advanced signal processing capabilities, variable range input, and convenient USB programming make this instrument a very versatile temperature measurement device. 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.
IMPORTANT: To prevent damage or errors from grounded PCs and surges, Acromag strongly recommends use of their USB-ISOLATOR when configuring a TT230 Series transmitter.
USB Connector: USB Mini-B type socket, 5-pin.
USB Data Rate: 12Mbps. USB v1.1 and 2.0 compatible.
USB Transient Protection: Transient voltage suppression on power and data lines.
USB Cable Length: 5.0 meters maximum.
Driver: Not required. Uses built-in Human Interface Device (HID) USB drivers of the Windows operating system.
Default Configuration: Pot/slidewire, 0% to 100% input, 4-20mA output, downscale break detect, medium filter.
Input Configuration: Two- or three-wire sensor input connections.
User-configurable thermistor linearization table haspreset curves for resistances below at 25°C.
Programs in °C, °F, °K, or ohmic integer values only.
|Input Type||Input range||Accuracy|
|Potentiometer||0 to 100%
(100 to 100KΩ)
|< ±0.01% of span|
|100 to 1MΩ
-40 to 100°C
(-40 to 212°F)
|< ±0.5% of input|
|Thermistor 2252Ω||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 2752Ω||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 2795Ω||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 3kΩ||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 5kΩ||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 10kΩ||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Thermistor 30kΩ||-40 to 100°C||< ±0.05°C (±0.09°F)|
|Custom thermistor||100 to 1MΩ||< ±0.5% of input|
Input Scaling Adjust: Zero: 0 to 95% of range, typical. Full scale: 5 to 100% of full scale range, typical.
Excitation Voltage: Thermistor/rheostat: 1.25V DC, typical. Potentiometer: 0.3V DC, limited to 3.35mA, typical.
Lead Break (Sensor Burnout) Detection: Configurable for either upscale or downscale on thermistor or rheostat inputs. Downscale only on potentiometer/slidewire inputs.
Output Range: 4 to 20mA DC.
Under-range capability 3.5mA.
Over-range capability 24mA.
Output Compliance: Rload = (Vsupply - 11V) / 0.020A.
Rload = 0 to 650 ohms @ 24V DC.
Output DAC Resolution: 16-bit D/A converter
Output Accuracy: Better than ±0.05% of span, typical (±0.1% max.) for for nominal input spans. Includes the effects of repeatability, terminal point conformity, and linearization, but does not include sensor error.
Ambient Temperature Effect: Better than ±0.008% per °C of input span or ±80ppm/°C, typical. Includes the combined effects of zero and span drift over temperature.
Output Response Time (for step input change)
No filter: 11ms. Medium filter: 150ms.
Low filter: 40ms. High filter: 1200ms.
Operating temperature: -40 to 80°C (-40° to 176°F).
Storage temperature: -40 to 85°C (-40 to 185°F).
Relative humidity: 5 to 95% non-condensing.
Power Requirement: 12-32V DC SELV (Safety Extra Low Voltage), 24mA maximum.
Shock and Vibration Immunity: Vibration: 4g, per IEC 60068-2-64. Shock: 25g, per IEC 60068-2-27.
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 61000-4-5.
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.
General: General-purpose enclosure designed for mounting on 35mm “T-type” DIN rail.
Case Material: Self-extinguishing polyamide, UL94 V-0 rated, color light gray. General-purpose NEMA Type 1 enclosure.
I/O Connectors: Removable plug-in terminal blocks rated for 12A/250V; AWG #26-12, stranded or solid copper wire.
Dimensions: 12.5 x 114.5 x 99.0 mm (0.5 x 4.51 x 3.90 inches).
Shipping Weight: 0.22 kg (0.5 pounds) packed.
Features & Benefits
- Easy setup and digital calibration via USB with Windows configuration software
- Interfaces 100-100kΩ potentiometer/slidewire and 100-1MΩ NTC thermistor/rheostat inputs
- Customizable thermistor linearization table with preset curves for popular resistances
- 1500V isolation between input/output circuits
- Space-saving 12.5mm (0.5 inch) unit with pluggable terminals for convenient wiring
- High accuracy, linearity, stability, and reliability
- Supports normal or reverse-acting output
- Supports sink or source output wiring
- User-selectable filtering (none, low, med., high)
- Fast response (as low as 11ms)
- Selectable upscale or downscale operation for sensor errors and lead-break detection
- NAMUR-compliant output loop current
- Shock (25g) and vibration (4g) resistant
- Wide ambient operation (-40 to 80°C)
- CE compliant. UL/cUL Class I Div 2, ATEX / IECEx Zone 2 approvals