Description
The ABB DO815 (3BSE013258R1) is an 8-channel, 24 V DC high-current digital output module engineered for the S800 I/O distributed architecture within System 800xA and Freelance control systems. Operating as a current-sourcing (high-side) transistor driver array, it delivers up to 2 A of continuous current per channel. This makes it suitable for direct control of high-power industrial inductive loads—such as heavy-duty solenoids, hydraulic valves, contactor coils, and filament lamps—without requiring intermediate interposing relays.
Commercial and Availability Status
- Product Condition: New Original (Factory Sealed / New Surplus) or Bench-Tested Refurbished/Exchange Units
- Warranty: 12-Month Industrial Warranty
- Estimated Lead Time: 1–3 business days (Global express dispatch)
- Pricing Note: Unit pricing is subject to active factory lead times and spot market availability. Contact our parts desk for a firm, itemized commercial quote.
Technical Specifications
| Parameter | Value |
| Model Number | DO815 |
| ABB Part Number | 3BSE013258R1 |
| Output Type | Digital Output / Transistor Current Sourcing (High-Side Driver) |
| Number of Channels | 8 channels (Divided into 2 individually isolated groups of 4) |
| Rated Operating Voltage | 24 V DC nominal (Acceptable supply spectrum: 10 to 32 V DC) |
| Max Continuous Current | 2 A per channel (Max load capacity per module is constrained by MTU parameters) |
| Minimum Load Impedance | < 0.25 \Omega internal on-state impedance |
| Isolation | Groupwise galvanic isolation from system ground (50 V rated insulation) |
| Max Cable Distance | 600 meters (656 yards) |
| Power Dissipation | 4 W typical |
| ModuleBus Current Drop | 120 mA typical (150 mA maximum) from +5 V DC rail |
| Maximum Filament Lamp Load | 10 W per channel |
| Mechanical Keying Code | AA |
| Dimensions | 45 mm (W) × 102 mm (D) × 119 mm (H) |
| Weight | 0.20 kg (0.44 lbs) |
| Environmental Hazard Certs | G3 Conformal Coating (ISA-S71.04), Class I Div 2 cULus, ATEX Zone 2 |
| Marine Class Approvals | ABS, BV, DNV, LR |
System Integration and Field Constraints
Advanced On-Board Diagnostics
The DO815 features hardware supervision mechanics per channel. It monitors open-loop and load faults on active channels, passing these flags up to the engineering workspace (e.g., Control Builder M).
- Short-Circuit and Overload Protection: Built-in current limiting circuits dynamically clamp fault current if an external output is shorted to ground or positive supply.
- Fault Operation Modes: The module supports two selectable runtime fault profiles:
- Automatic Reset Mode: Automatically attempts to re-engage the output switch once the physical overload thermal threshold cools down.
- Fault Latching Mode: Trips the internal electronic breaker upon detecting a fault condition, holding the channel off until software issues an explicit reset command.
Output Status Pattern (OSP) Execution
If communication with the parent controller (e.g., PM864 or CI801 ModuleBus cluster head) drops out, the onboard OSP logic activates. Rather than defaulting to unmanaged dropouts, the DO815 forces each channel into a predetermined, safety-cleared configuration (Hold Last Value, Force ON, or Force OFF) defined during structural system staging.
Termination Unit Selection
Mechanical Warning: The DO815 uses keying code AA. It must only be installed onto compatible Module Termination Units (MTUs) such as the TU810, TU812, TU814, or TU830. Forcing the module onto an incorrect backplane configuration will fracture the rear guide moldings.
Thermal Derating Constraints: When installing the module inside tight enclosures using a compact MTU configuration, the maximum allowable ambient thermal ceiling drops from +55 °C down to +40 °C if vertical mounting formats are selected. Ensure field panels maintain sufficient airflow or active fan extraction to prevent thermal tracking shutdowns under full 2 A channel saturation.
Frequently Asked Questions
Does the DO815 require flyback diodes when switching heavy inductive solenoid coils?
No. The DO815 incorporates high-capacity inductive load suppression components within its output block. However, if the field cable runs approach the 600-meter limit, adding an external flywheel diode right at the coil terminal box is a recommended field practice to clamp localized electromagnetic noise back-EMF.
What causes a channel fault LED to illuminate when the output command is active?
This usually points to an open-load threshold violation (load current dropping below the minimum active sensor floor), an external field wiring short-circuit to ground, or an undervoltage state on that specific isolated channel group’s 24 V DC external feed.
Can the DO815 be extracted or replaced while the remaining S800 I/O rack is active?
Yes. The module supports hot-swap operational behavior (Removal and Insertion Under Power). Provided your system is configured to permit Hot Configuration in Run (HCIR), pulling the module will only fault the specific I/O loop associated with this module’s slot without destabilizing upstream controller tasks. Ensure standard electrostatic discharge safety measures are practiced during field handling.
