Description

ABB TU833 Extended Module Termination Unit

The ABB TU833 3BSE038726R1, also cataloged as the TU833 Extended Module Termination Unit, provides field termination, process voltage distribution, and ModuleBus signal routing for ABB S800 I/O modules. It supports up to 16 I/O channels and two individually isolated process voltage groups.

Hardware Specifications

Parameter	Specification
Model	TU833 3BSE038726R1
Brand	ABB
Product Type	Extended Module Termination Unit
Article Number	3BSE038726R1
Weight	0.28 kg (0.6 lbs)
Dimensions	126 mm W x 105 mm H x 64 mm D, including connector and terminals
Operating Temp	0 to +55 deg C (+32 to +131 deg F); approvals issued for +5 to +55 deg C
Storage Temp	-40 to +70 deg C (-40 to +158 deg F)
Power Consumption	Not specified in supplied data
Number of Channels	16 I/O channels
Maximum Rated Voltage	50 V
Maximum Current per I/O Channel	2 A
Maximum Current Process Connection	5 A
Process Voltage Groups	2 individually isolated groups
Process Voltage Fuse	6.3 A fuse per group
Connection Type	Crimp Snap-in connector
Process Connections	56
I/O Connections	2 terminals per channel
ZP Connections	1 ZP connection per channel
Process Power Connections	4 x 6.3 A
Process Power 0 V Connections	10 x 2
Mounting	Standard DIN rail
Mounting Direction	Both directions
Mounting Lock	Mechanical DIN rail latch
Single/Redundant I/O	Single
Acceptable Wire Size	Solid: 0.2 - 2.5 mm2, 24 - 12 AWG; Stranded: 0.2 - 2.5 mm2, 24 - 12 AWG
Terminal Wiring	One wire per terminal
Wire Stripping Length	6 mm
Dielectric Test Voltage	500 V AC
Protection Class	IP20 according to IEC 60529
Pollution Degree	Degree 2, IEC 60664-1
Relative Humidity	5 to 95 %, non-condensing
Corrosion Protection	ISA-S71.04: G3
Mechanical Conditions	IEC/EN 61131-2
EMC	EN 61000-6-4, EN 61000-6-2
Electrical Safety	EN 61010-1, UL 61010-1, EN 61010-2-201, UL 61010-2-201
Hazardous Location	C1 Div 2 cULus, C1 Zone 2 cULus, ATEX Zone 2
Marine Certification	DNV-GL, BV, LR
Equipment Class	Class I according to IEC 61140, earth protected
RoHS	EN 50581:2012
WEEE	Directive 2012/19/EU
Compatible I/O Modules	AI810, AI815, AI820, AI830, AI830A, AI835, AI835A, AI843, AI845, AO810, AO810V2, AO815, AO820, AO845, AO845A, DI810, DI811, DI814, DI830, DI831, DI840, DI880, DI885, DO810, DO814, DO815, DO840, DO880, DP820, DP840

ABB S800 ModuleBus and I/O Architecture

The TU833 distributes the ModuleBus from the installed I/O module to the next MTU. It also generates the required module address by shifting outgoing position signals toward the next MTU.

Furthermore, the 16-channel configuration provides two I/O terminals per channel and one ZP connection per channel. This arrangement supports direct field termination while maintaining the physical addressing sequence across the S800 I/O installation.

The TU833 also separates process voltage connections into two individually isolated groups. Each group uses a 6.3 A fuse, while the maximum rated current remains 2 A per I/O channel. Therefore, the application should select fuse ratings according to the actual load requirements and system power design.

The MTU supports a defined set of ABB S800 I/O modules, including analog input, analog output, digital input, digital output, and related interface modules. Consequently, engineers should verify the installed I/O module against the specified compatibility list before commissioning.

Frequently Asked Questions (FAQ)

Q: How many I/O channels does the ABB TU833 support?

A: The TU833 supports up to 16 I/O channels. Each channel provides two I/O connections and one ZP connection.

Q: How does the TU833 handle process voltage distribution?

A: The TU833 provides two individually isolated process voltage groups. Each group has a 6.3 A fuse, while the maximum rated voltage is 50 V.

Q: How does the TU833 generate the I/O module address?

A: The MTU shifts the outgoing position signals to the next MTU. This process generates the correct address for the connected S800 I/O module.

Field Installation Guidelines

• Mount the TU833 on a standard DIN rail and engage the mechanical latch before wiring.
• Confirm that the mounting direction and available cabinet clearance match the installation arrangement.
• Connect field wiring according to the assigned channel and terminal configuration.
• Use solid or stranded conductors within the specified 0.2 - 2.5 mm2 wire range.
• Use only one wire per terminal and maintain the specified 6 mm stripping length.
• Verify the process voltage group assignment before connecting field power.
• Check the fuse arrangement for each isolated process voltage group against the application load.
• Route process wiring separately from high-noise power conductors where the cabinet design permits.
• Verify protective earth and cabinet grounding according to the applicable installation standard.
• Confirm the connected I/O module appears in the specified compatible module list.
• Check ModuleBus continuity and the physical MTU sequence before commissioning.
• Inspect all crimp snap-in connections for secure mechanical engagement before energizing the system.
• Do not exceed the 50 V maximum rated voltage or 2 A maximum current per I/O channel.
• Verify operating ambient temperature remains within the specified range during normal operation.

Specifications

• Brand: ABB

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems