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Phone: +86 16626708626Description
Product Core Brief
- Model: 3BHB003689
- Brand: ABB
- Series: Symphony Plus / 800xA DCS
- Core Function: 16-channel digital output control
- Product Type: Relay output interface module
- Key Specs: 24 VDC, 2 A per relay, -25°C to +70°C
- Condition: New Surplus
Key Technical Specifications
- Outputs: 16 dry contact relays (2 A at 24 VDC max)
- Power supply: 24 VDC ±15% (1.5 A max backplane)
- Operating temperature: -25°C to +70°C (derate above 55°C)
- Dimensions: 100 x 50 x 120 mm
- Weight: 380 g
- HS Code: 8537.10.9090
- Isolation: 2 kV channel-to-bus
- Response time: <10 ms on/off
- Contact rating: 60 VDC / 30 VAC resistive
- Mounting: 19″ rack standard (3U height)
- 3BHB003689
Product Introduction
ABB 3BHB003689 is a 16-channel digital output module for Symphony Plus and 800xA DCS systems, switching field devices like solenoids, valves, and annunciators via isolated dry contacts. Installs in standard I/O racks as remote drop or local expansion.
Each relay handles 2 A continuous at 24 VDC with mechanical life exceeding 10 million cycles. Hot-swap capable minimizes downtime in continuous processes. Field deployments in packaging lines run reliably through voltage spikes—vertical mount with 50 mm clearance topside for heat. Verify backplane addressing before scan.
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| All relays stuck open | 24 VDC <20 V or backplane interlock | ✅ High | Measure field supply at COM; toggle %Q001 manual | Check 1.5 A fuse; cycle rack power in STOP |
| Relay 7 chatters 1 Hz | Inductive kickback >50 V or snubber fail | ✅ High | Scope flyback >30 V; add RC snubber 0.1 µF/100 Ω | Verify diode across coil loads; MOV for AC |
| No hot-swap detect | Firmware mismatch or slot EEPROM | ✅ Medium | Rack HMI shows empty slot; reseat 3x firm | Update controller firmware; clear slot config |
| Contact weld on ch12 | Overload >2 A sustained or weld from arc | ✅ High | Resistance <0.1 Ω closed; burnish contacts | Load shed test; replace if pitted >0.5 mm |
| Rack-wide DO scan fail | Bus terminator missing or address clash | ❌ Low | CS31 continuity 120 Ω ends; unique slot # | Document old DIPs; power sequence head first |
Capture %Q status snapshot before reset. DO modules fail from arcing 75%—snubbers save lives. Photo welded contacts for warranty.
Frequently Asked Questions (FAQ)
Dry or wet contacts—field power separate?
Dry contacts only—no internal 24 VDC. External wetting required. Common COM per 8 channels max.
Hot-swap safe during process?
Yes—module handshake prevents glitches. Rack firmware v5.2+ required. Pull straight, no twist.
Inductive loads like solenoids safe?
Yes to 20 VA with external diode/RC. No suppression = relay death in 10K cycles. Flyback spikes kill.
Rack slot position restrictions?
Slots 3-16 typical; avoid power supply neighbors (heat). Vertical orientation only.
❗ Deadly wiring mistake?
❗ Shields grounded both ends—massive ground loops weld relays instantly. Single-end ground station side. Torched a whole rack once
Condition and incoming test?
New Surplus: OEM stock, full 2 A cycle test all 16 relays + isolation hi-pot. Mechanical action verified; no sticky contacts. Reports ready.
Warranty, stock dispatch?
1-year DOA. In stock, ships after 24-hour relay burn-in. Same-day before 2 PM.
