Product Core Brief

• Model: 8115-DO-DC
• Brand: Emerson (PAC8000 I/O)
• Series: PAC8000 Modular I/O Platform
• Core Function: 8-channel digital output module for driving relays, solenoids, indicators, and other DC loads.
• Product Type: Discrete Digital Output Module
• Output Type: 8-point source, non-isolated, module powered
• Condition: New Original / New Surplus (subject to available stock)

Key Technical Specifications

• Part Number: 8115-DO-DC
• Platform: Emerson PAC8000 Modular I/O
• Output Count: 8 channels
• Output Type: Source output, non-isolated, module powered
• Output Voltage Range: 2–60 VDC
• Switched Current per Channel: 1 A continuous
• Maximum Module Current: 3 A total per module
• Response Time: 1 ms
• ON Voltage Drop: 0.25 V max
• OFF Leakage Current: 1.0 mA max
• Railbus Current: 125 mA max (system side)
• Field Power: 2–60 VDC bussed field power required
• Special Capabilities: Discrete or pulsed outputs
• Mounting: PAC8000 carrier with Railbus interconnect
• Field Terminals: Snap-on terminal block, field-replaceable
• Application: General purpose and hazardous area installations

 

Product Introduction (No Fluff)

The Emerson 8115-DO-DC is an 8-channel digital output module for the PAC8000 modular I/O platform. It provides eight source-type outputs rated at 2–60 VDC and 1 A pe

r channel, making it suitable for driving relays, solenoids, pilot lights, and other DC field devices.

The module is non-isolated and module powered, drawing up to 125 mA from the PAC8000 Railbus. Field power is supplied through the bussed 2–60 VDC field supply. Each channel can switch up to 1 A continuously, with a total module current limit of 3 A. The ON-state voltage drop is limited to 0.25 V max, and OFF leakage is 1.0 mA max.

The module supports both discrete and pulsed output modes with a 1 ms response time. Field wiring connects through a snap-on terminal block that can be replaced in the field without rewiring. The PAC8000 platform supports general purpose and hazardous area applications, with communication handled through a selectable Bus Interface Module or controller.

 

QA & Testing SOP (Dynamic & Transparent)

Digital output modules are critical for actuator and relay control. Each surplus unit undergoes:

1. Part Number Verification: Confirm the module label reads 8115-DO-DC exactly. Check for PAC8000 platform markings.
2. Visual Inspection: Inspect the module housing, connector pins, and snap-on terminal block for corrosion, bent pins, or physical damage.
3. Railbus Connection Check: Verify the module seats properly in a PAC8000 carrier. Confirm Railbus contacts are clean and free of oxidation.
4. Channel Output Test: Command each of the eight outputs ON/OFF. Verify the output voltage matches the applied field power within tolerance.
5. Current Capacity Check: Verify each channel can sustain 1 A continuous without excessive voltage drop or overheating.
6. Pulsed Output Test: Test pulsed output mode to confirm the 1 ms response time specification.
7. Leakage Current Test: With outputs OFF, measure leakage current. Confirm it does not exceed 1.0 mA.
8. Packaging: Pack in anti-static bags with foam cushioning. Protect connector pins and terminal block during transit.

 

Installation Pitfalls & Guide (Engineer to Engineer)

Verify total module current does not exceed 3 A. While each channel is rated for 1 A, the module total is limited to 3 A. Loading all eight channels at 1 A simultaneously will exceed the module rating. Plan your load distribution accordingly.

Confirm field power supply voltage. The module requires 2–60 VDC bussed field power. Applying voltage outside this range can damage the outputs or connected devices.

Check Railbus power budget. The module draws up to 125 mA from the Railbus. Ensure the carrier power supply can support the total current draw of all modules on the node.

Note the non-isolated design. The outputs are non-isolated and share a common reference. If isolation between channels or from the backplane is required, consider a different module type.

Configure fault-safe state. The PAC8000 platform allows configurable output behavior on communication loss (timeout). Set the fault-safe state (OFF, ON, or hold last value) to match your process safety requirements.

Replace terminal blocks carefully. The snap-on terminal block is field-replaceable. If damaged, swap it with an identical PAC8000 terminal block to maintain the mechanical keying system.

Installation Steps:

1. Pre-install: Confirm part number 8115-DO-DC. Verify the PAC8000 carrier is powered down. Check the Railbus power budget.
2. Mount: Snap the module onto the PAC8000 carrier. Verify it seats fully and the Railbus connector engages.
3. Wire: Attach the snap-on terminal block. Connect field devices per the output channel assignments. Apply 2–60 VDC field power.
4. Commission: Power up the carrier. Configure each output channel via the BIM/controller. Test each output individually. Verify fault-safe behavior on communication loss.

Technical FAQ

1. What is the difference between 8115-DO-DC and relay output modules? The 8115-DO-DC uses solid-state source outputs (2–60 VDC, 1 A/ch), not mechanical relays. It offers faster switching (1 ms) and longer life but is limited to DC loads within the voltage/current ratings.

2. Can I use all eight channels at 1 A simultaneously? No. Each channel supports 1 A continuous, but the total module current is limited to 3 A. You must distribute the load so the sum of all active channels does not exceed 3 A.

3. Is this module isolated? No. The 8115-DO-DC is non-isolated and module powered. All outputs share a common reference with the module power supply.

4. Can this module drive solenoid valves? Yes, provided the solenoid voltage is within 2–60 VDC and the current draw per channel does not exceed 1 A. Watch the 3 A total module limit when driving multiple solenoids.

5. What happens on communication loss? The PAC8000 platform supports configurable fault-safe states. Outputs can be set to go OFF, ON, or hold their last value when communication with the BIM/controller is lost. Configure this per your process safety requirements.

6. What warranty do you offer on surplus stock? Terms vary by condition and availability. For surplus industrial modules, we typically provide a short functional guarantee. Confirm details at time of order.

Note: The 8115-DO-DC is an Emerson PAC8000 module. PAC8000 was originally a GE Fanuc/GE Intelligent Platforms product line and is now part of Emerson following the acquisition. It is commonly found in Emerson process control, SCADA, and industrial automation systems.