PRODUCT INFORMATION
Product Overview
The Allen-Bradley 1746-NT4 SLC 500 Analog Input Module provides digitally converted thermocouple and millivolt data. It delivers this information directly to SLC 500 processors through the image table. The module features four backplane isolated input channels. Supported thermocouple types include J, K, T, E, R, S, B, and N. Direct millivolt input ranges include plus-or-minus 50 mV and plus-or-minus 100 mV.
The module installs in any SLC 500 chassis slot except slot 0. It receives 5 Volts DC and 24 Volts DC directly from the backplane. No external power supply is required for operation. Two cold-junction compensation sensors preserve thermocouple signal accuracy. Five green LED status indicators show operating states for the module and each channel.
TECHNICAL DATA
Technical Specifications
| Parameter | Specification |
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| A/D Conversion method | Sigma-delta modulation |
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| Backplane Current | 0.06 mA @ 5VDC; 0.04 mA @ 24VDC |
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| Backplane Current (24 Volts) | 55 milliamps |
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| Backplane Current (5 Volts) | 60 milliamps |
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| Backplane Power Consumption | 0.8W maximum (0.3W @ 5V dc, 0.5W @ 24V dc) |
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| Category | PLCs |
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| Channels | 4 backplane isolated |
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| Compatible Thermocouple Sensors | J, K, T, E, S, R, B and N |
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| Compatible miliVolt signal | +/- 50 mV and +/- 100 mV |
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| I/O Chassis location | Any slot except Slot 0 |
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| Inputs | 4 |
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| Module Type | Thermocouple/mV Analog Input Module |
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| No. of Inputs | Four (4) |
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| Open Circuit Detection | Zero; Upscale; Downscale |
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| Operating Temperature | 0 to 60 degrees Celsius |
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| Resolution | 16 bits in, 14 bits out |
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| Step Response | 60 milliseconds in, 2.5 milliseconds out |
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| Storage Temperature | -40 to 85 degrees Celsius |
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| UPC | 662468165914 |
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| Update Time | 26 milliseconds-1.2 seconds |
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| Weight | 1.00 lbs (0.45 kg) |
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TECHNICAL INFORMATION
Features
- Four backplane isolated analog input channels
- Interfaces with thermocouple types J, K, T, E, R, S, B, and N
- Accepts direct plus-or-minus 50 mV and plus-or-minus 100 mV signals
- Sixteen-bit converter resolution utilizing sigma-delta modulation
- Two integrated cold-junction compensation sensors maintain input accuracy
- Selectable channel filter frequencies at 10 Hz, 50 Hz, 60 Hz, and 250 Hz
- Configurable open-circuit detection settings for zero, upscale, or downscale response
- Five green LED indicators provide module and individual channel status
TECHNICAL INFORMATION
Applications
- Thermocouple temperature measurement in SLC 500 systems
- Millivolt analog signal acquisition for SLC 500 processors
- Cold-junction compensated temperature monitoring across channels
TECHNICAL INFORMATION
Connections / Interfaces
- Supports two wires per terminal with up to 14 AWG or 2.5 mm2 wire size.
- Requires shielded twisted thermocouple extension wire for thermocouple inputs.
- Requires Belden 8761 or equivalent shielded cable for millivolt inputs.
- Maximum allowable cable impedance is 25 ohms.
TECHNICAL INFORMATION
Installation Guidelines
- Install the unit into any available SLC 500 chassis slot except slot 0.
- Slot 0 is reserved exclusively for the SLC 500 system processor.
- Disconnect system power prior to inserting or removing the module from the chassis.
- Maintain a maximum cable impedance of 25 ohms per loop.
TECHNICAL INFORMATION
Configuration Guidelines
- Configure open-circuit fault behavior to zero, upscale, or downscale per channel.
- Select digital filter frequencies to minimize 50 Hz or 60 Hz line noise.
- Input filters are automatically bypassed when cold junction compensation input is selected.
- Block transfers are required when operating within a remote I/O configuration.
TECHNICAL INFORMATION
Compatibility
- Compatible with SLC 500 processors and 1746 chassis assemblies
- Installs in any chassis slot except slot 0
- Interfaces with thermocouple types J, K, T, E, R, S, B, and N
- Compatible with +/-50 mV and +/-100 mV analog signal sources
COMPATIBILITY
Compatibility & Replacement
COMPATIBLE MODELSCompatible with SLC 500 processors and 1746 chassis assemblies Installs in any chassis slot except slot 0 Interfaces with thermocouple types J, K, T, E, R, S, B, and N Compatible with +/-50 mV and +/-100 mV analog signal sources
Verify compatibility against the exact Part Number, revision and manufacturer documentation before ordering.
PART VERIFICATION
Before You Order
Industrial automation parts can share similar model names, suffixes and revisions. Confirm the complete manufacturer Part Number before purchase.
01Check Part NumberMatch the complete ordering code on the existing unit.
02Confirm RevisionCheck suffix, hardware or firmware when applicable.
03Send a Label PhotoWe can review a clear label photo when identification is uncertain.
ORDERING PROCESS
From RFQ to Dispatch
1Submit Part Number2Verify Product Identity3Confirm Stock & Condition4Issue Quotation5Dispatch & Tracking
PRODUCT FAQ
Frequently Asked Questions
Which thermocouple types are compatible with the Allen-Bradley 1746-NT4?
The module supports thermocouple types J, K, T, E, R, S, B, and N.
Can the 1746-NT4 module be installed in slot 0 of an SLC 500 chassis?
No. Slot 0 is reserved exclusively for the SLC 500 processor.
Does the 1746-NT4 require an external power supply?
No. It receives 5 Volts DC and 24 Volts DC directly through the backplane.
How does the module respond to an open circuit or broken sensor?
Each channel can be configured to force readings to zero, upscale, or downscale.
