Description

1. Product Overview

ABB TU836V1 (Part No.: 3BSE013237R1) is an extended 8-channel terminal mounting base (MTU Module Terminal Unit) of the S800 I/O series, compatible with the AC 800M DCS distributed remote I/O control system. It is specially matched with high-voltage digital output modules such as DO820 and DO821. As a passive transition base between field high-voltage equipment cables and I/O modules, multiple bases can be daisy-chained via the built-in ModuleBus backplane bus, which automatically assigns a unique hardware address to each I/O module without manual DIP switch setting, effectively eliminating faults like duplicate I/O addresses and configuration matching errors.

With a maximum rated withstand voltage of 250VAC/DC and a rated load current of 3A per channel, the unit adopts a 2-group electrically isolated 4-channel structure, each channel equipped with an independent loop fuse. Fitted with mechanically coded anti-misplug lock strips, it physically prevents hardware burnout caused by wrong insertion of different types or high/low voltage I/O modules. Designed for bidirectional mounting on standard 35mm DIN rails, it features Industrial Class A EMC performance and wide-temperature adaptability. Widely applied to high-voltage actuator signal control scenarios such as 220V solenoid valves and relays in thermal power, chemical, oil & gas, metallurgy and water treatment industries, it is commonly used for wiring of new high-voltage DO measuring points, spare replacement of legacy extended S800 terminal bases, and capacity expansion renovation of DCS systems.

2. Hardware Structure and Composition

2.1 Dual 4-Channel Fused Field Signal Wiring Unit

The unit is divided into two electrically independent signal loops with 4 channels each, 8 channels in total. Each channel is equipped with a fused load power terminal and a signal return terminal for connecting field high-voltage equipment including 220VAC solenoid valves, contactors, valve actuators and relays. Two sets of isolated common process power terminals support separate power supply for the two loops to suppress inter-group electrical crosstalk, and adapt to both grouped and independent wiring modes. The terminals accept solid wires (0.2~4.0mm²) and stranded wires (0.2~2.5mm²) with a recommended crimping torque of 0.5~0.6N·m, ensuring stable connection against long-term plant vibration to avoid loose wiring and signal interruption faults.

2.2 ModuleBus Backplane Bus Daisy-chaining & Automatic Hardware Addressing Unit

A passive high-speed ModuleBus backplane loop enables end-to-end daisy-chain expansion of multiple TU836V1 units, transmitting bus signals sequentially between adjacent bases. Hardware addresses are automatically allocated via backplane displacement encoding signals, enabling the controller to accurately identify each I/O channel without manual DIP switch or software configuration, avoiding address conflicts and misassigned measuring points and shortening the commissioning cycle of remote I/O stations.

2.3 Mechanically Coded Anti-misplug Safety Positioning Unit

Two groups of adjustable mechanical coding lock strips with 6 positions each provide 36 hardware positioning combinations. Exclusive physical lock positions are configured for various extended I/O modules, so only modules with matching codes can be inserted into corresponding slots. It fundamentally prevents chip breakdown and power short circuits caused by mixed use of high/low voltage or different types of modules, especially suitable for high-density control cabinets with mixed high and low voltage measuring points to reduce man-made hardware damage risks during installation and maintenance.

2.4 DIN Rail Mounting & Shielded Earthing Protection Unit

The base adopts a snap-on DIN rail locking structure supporting both horizontal and vertical cabinet installation. Integrated dedicated earthing contacts realize shield earthing when mounted on a grounded DIN rail to suppress common-mode electromagnetic interference. Made of flame-retardant high-temperature resistant engineering plastic with separated strong and weak current wiring areas, it is fully backward compatible with legacy MTU bases of the same series, allowing direct on-site replacement without large-scale modification to existing cables and rails, and supporting hot swapping of matched I/O modules for convenient maintenance.

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3. Technical Specifications

3.1 Electrical Specifications

Rated Withstand Voltage: Max. 250VAC/DC; dielectric withstand test: 2000VAC
Rated Current per Channel: 3A; maximum allowable current for common process loops: 10A
Channel Grouping: 2 electrically isolated loops (4 channels per group), each channel with independent loop fuse
Compatible Cable Specifications: Solid wire 0.2~4.0mm², stranded wire 0.2~2.5mm²; recommended wire stripping length: 7mm, crimping torque: 0.5~0.6N·m
Bus Type: Passive ModuleBus backplane daisy-chain bus, no external power supply required
Compatible Modules: S800 series high-voltage digital output extended I/O modules such as DO820, DO821
Number of Channels: 8 high-voltage process signal channels with independent fuses

3.2 Environmental Specifications

Operating Temperature (Horizontal Mounting): 0℃ ~ +55℃; Operating Temperature (Vertical Mounting): 0℃ ~ +40℃
Storage & Transportation Temperature: -40℃ ~ +70℃
Relative Humidity: 5%~95% RH, non-condensing, free of corrosive gas and conductive dust
EMC Compliance: IEC 61000 Industrial Class A anti-interference standard
Safety Certifications: CE, UL/cUL, FM explosion-proof certification, RoHS
Protection Class: IP20, only for indoor installation in ventilated and enclosed industrial control cabinets

3.3 Mechanical Specifications

Mounting Method: Bidirectional snap-on mounting on standard 35mm DIN rails
Overall Dimensions: W 120.5mm × D 64mm × H 110mm
Net Weight: Approx. 0.26kg
Enclosure Material: Flame-retardant high-temperature resistant engineering plastic
Optional Accessories: S800 series high-voltage DO modules, shielded signal cables, DIN earthing rails, original replacement fuses, terminal marking tags

4. Product Functions and Features

Independent single-channel fuse protection limits fault coverage of high-voltage loops

Only the fuse of the faulty channel will blow under short-circuit or overload conditions, without powering down the entire I/O module or bus loop, so other measuring points can maintain normal control output, effectively protecting high-voltage field equipment such as solenoid valves and contactors.

Dual isolated power supply architecture eliminates strong/weak current signal crosstalk

Two sets of isolated common power terminals allow separate power supply for two 4-channel loops, isolating interference between high-power output loops and low-power instrument signal circuits, adapting to complex field wiring with mixed actuators and transmitters.

Automatic bus addressing + daisy-chaining enables rapid large-scale remote I/O networking

No manual DIP switch address setting is required. Multiple terminal bases can be daisy-chained to centrally deploy multiple groups of 8-channel high-voltage measuring points, reducing configuration errors and meeting the demand for centralized signal collection in large industrial plants.

Physical anti-misplug design ensures hardware safety in mixed high/low voltage cabinets

Mechanical locking prevents mismatched module installation, fundamentally avoiding short-circuit burnout of hardware and greatly improving operational safety during installation and maintenance in high-density control cabinets.

Wide-temperature industrial design delivers long-term stable maintenance-free operation under harsh conditions

Supporting dual mounting orientations, the flame-retardant sealed enclosure with shield earthing provides excellent dustproof, moisture-proof and anti-interference performance for high-temperature, dusty industrial plants. Hot swapping of matched I/O modules avoids production shutdown during equipment maintenance.

5. Applicable Working Conditions and Application Scenarios

High-voltage DO measuring point wiring for AC800M DCS remote I/O stations in petroleum refining and coal chemical plants, for centralized control wiring of 220V solenoid valves, pneumatic actuators and contactors.
High-power digital output point wiring for auxiliary control systems including boilers, desulfurization, denitrification and water treatment in thermal power and waste incineration power plants, as well as signal conversion projects for local control cabinets.
Control signal wiring projects for high-voltage field equipment such as motor starters and valve switches in sequential interlock control systems of metallurgical, cement and papermaking production lines.
New construction and capacity expansion renovation of automatic control systems for municipal sewage and water supply plants, suitable for intensive isolated high-voltage loop wiring scenarios.
Spare replacement of aging faulty extended MTU terminal bases and hardware upgrading projects for high-voltage digital output I/O control cabinets of legacy S800 systems.

ABB TU836V1 3BSE013237R1 8-channel terminal mounting base