WhatsApp: +86 16626708626
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Phone: +86 16626708626Description
Product Core Brief
- Model: TU843 (3BSE021443R1)
- Brand: ABB
- Series: S800 I/O System
- Core Function: Terminal unit for I/O wiring
- Product Type: Redundant MTU (Module Terminal Unit)
- Key Specs: 16 channels | 50 V | 3 A max
- Condition: New Surplus (not refurbished)
- Inventory Status: Buffer stock for legacy S800 racks800xahardwareselector.automation.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Brand/Model | ABB TU843 3BSE021443R1 |
| Channels | Up to 16 I/O + 2+2 process voltage |
| Voltage Rating | 50 V max |
| Current Rating | 3 A per channel |
| Connections | 3-wire per channel + ZP |
| ModuleBus | Dual distribution to I/O and next MTU |
| Mounting | DIN rail with latch |
| Keying | 4 mechanical keys (36 configurations) |
| Dimensions | 131 mm W x 64 mm D x 186.5 mm H |
| Weight | 0.6 kg |
| Operating Temp | −25 to +55 °C800xahardwareselector.automation. |
| Certifications | RoHS |
Product Introduction & Supply Chain Strategy
The ABB TU843 3BSE021443R1 is a redundant Module Terminal Unit (MTU) for S800 I/O systems. It handles field wiring distribution for up to 16 channels in DCS setups across refineries, power plants, and pulp mills.800xahardwareselector.automation.
New Surplus mitigates lead time variability on discontinued S800 parts. Refurbished MTUs risk poor contact resistance causing I/O dropouts. Maintain Min/Max 1/2 units per rack to cut stock-outs without excess obsolescence write-offs.
- TU843
Installation & Configuration Guide
Stage 1: Pre-Installation
Lock out/tag out I/O rack power. Tools: ESD strap, torque screwdriver (0.5 Nm), DIN rail cutter, camera for keying positions. Verify MTU keying matches I/O modules above/below.
Stage 2: Removal
Disconnect field wires by label. Release DIN latch, slide MTU leftward off rail. Inspect for terminal corrosion or bent ZP pins.800xahardwareselector.automation.
Stage 3: Installation
Set 4 mechanical keys to match I/O types (prevents mismatch). Snap onto DIN rail, secure latch for ground. Reconnect wires: I/O pairs + ZP per channel.
Stage 4: Power-On & Testing
Power rack, scan ModuleBus via CI847. Check continuity on all 16 channels with meter. Verify no open circuits; simulate field power distribution.
Firmware/Software Versions & Upgrade Notes
TU843 is passive hardware—no firmware. Keys provide mechanical config only. Mismatch with I/O modules blocks insertion; always photo old keys. No compatibility issues across 800xA revisions.800xahardwareselector.automation.
Frequently Asked Questions (FAQ)
True New Surplus confirmation?
Yes—factory DIN latch intact, zero terminal wear. Unlike field returns with oxidized contacts.
Price vs OEM or used rationale?
Sourced globally 25% under list, skips refurb contact failures. One plant lost $60k from intermittent I/O on “bargain” MTU
EOL—strategic stocking?
S800 legacy component; plan last-time-buy. Min/Max 1/2 per remote site to handle vendor consolidation gaps.
Live replacement possible?
No—ModuleBus and field power require isolation. Hot-swap damages addressing chain.
Does it store any config?
Purely mechanical/electrical pass-through. I/O config lives in head unit.
Warranty and test protocol?
1-2 years; QC covers insulation resistance, ZP continuity, keying verification. Serial traceable
Keying setup for my modules?
4 keys (2 per slot) offer 36 combos—match exactly to AI/AO/DI/DO above/below. Prevents wrong insertion.
