Connecting Your IRB 6700: Power, Signal, and Customer Cable Guide

Connecting your ABB IRB 6700 robot to its IRC5 controller is a fundamental step after physically installing both units. Proper cabling ensures not only functionality but also safety and reliable communication within the robot system. This guide clarifies the standard and optional electrical connections, going beyond the basic manual descriptions to offer practical insights for installation technicians, commissioning engineers, and maintenance personnel.

Prerequisite

Before proceeding with any electrical connections, ensure both the IRB 6700 manipulator and the IRC5 controller cabinet are securely fastened to their foundations as per the installation guidelines. Attempting connections before securing the units can be hazardous and may damage equipment.

Understanding the Core Connections: Robot vs. Customer Cables

The cabling between the IRB 6700 and its controller falls into two main categories:

Robot Cables (Standard)

These are the essential lifelines included with the standard robot delivery. They handle the fundamental power and communication required for the robot's operation.

Customer Cables (Optional)

These cables facilitate communication and power exchange between the robot system and specific equipment you add, such as grippers, sensors, external safety devices, or communication links to PLCs. Their use depends entirely on your application's requirements.

The Lifelines: Standard Robot Cables (Power & Signal)

ABB simplifies the core setup by providing pre-manufactured, plug-and-play cables for the robot's essential functions. These handle the power delivery to the motors and the critical feedback signals from the robot's internal measurement system.

Robot Power Cable

Purpose: Delivers the high-voltage drive power from the IRC5 controller's drive units to the robot's axis motors. This is what enables the robot's physical movement.
Connection: Runs between the R1.MP connector on the robot base and the XS1 connector on the IRC5 controller cabinet.

Robot Signal Cable

Purpose: Transmits crucial feedback data from the robot's axes back to the controller. This includes position information (from resolvers/encoders) processed by the Serial Measurement Board (SMB) located within the robot, as well as other status signals.
Connection: Runs between the R1.SMB connector on the robot base and the XS2 connector on the IRC5 controller cabinet.

Cable Connection Diagram

graph LR subgraph IRC5["IRC5 Controller"] XS1["XS1 Connector
(Power)"] XS2["XS2 Connector
(Signal)"] IO["Customer I/O
Interfaces"] end subgraph IRB6700["IRB 6700 Robot"] R1MP["R1.MP Connector
(Power In)"] R1SMB["R1.SMB Connector
(Signal Out)"] CUST["Customer Interface
(Optional)"] end XS1 -->|"Robot Power Cable
(7-30m)"| R1MP R1SMB -->|"Robot Signal Cable
(7-30m, Shielded)"| XS2 IO -.->|"Customer Cables
(Application Specific)"| CUST classDef controller fill:#3a51e8,stroke:#293486,color:white; classDef robot fill:#5272f2,stroke:#293486,color:white; classDef cable stroke-dasharray: 5 5; class IRC5,XS1,XS2,IO controller; class IRB6700,R1MP,R1SMB,CUST robot;

Practical Insight: Choosing the Right Cable Length

The manual (page 96) lists standard lengths for both power and signal cables (typically 7m, 15m, 22m, and 30m). Selecting the appropriate length during the initial order or replacement is crucial:

Avoid Strain: Ensure the cable is long enough to reach between the controller and robot base without being taut, especially considering the robot's potential movement if mounted on a track or gantry.
Minimize Slack: Excessively long cables can create trip hazards, get easily damaged, and complicate cable management within the cell.
Cell Layout: Choose the length that best suits your specific installation layout, allowing for neat routing and proper strain relief.

Expanding Capabilities: Optional Customer Cables

These cables are specified and installed based on the unique needs of your automation task.

Purpose:
To integrate tooling, sensors, actuators, safety equipment, or establish communication links (like databus) required by your specific application. They essentially extend the controller's I/O and communication capabilities to the manipulator arm or external devices.
What they Carry:
This can range from low-voltage signals for sensors, high-voltage power for certain tools (within specified limits), to dedicated network communication lines. Protective ground (PE) connections are also typically included for safety.
Key Reference:
Crucially, the specifics of customer cabling (connection points, pinouts, configuration) are detailed in the Product manual for the IRC5 controller (refer to document number in the manual's References section, page 10). This is because these connections interface directly with the controller's configurable I/O boards and system parameters.

Integrating Application Equipment: DressPack/SpotPack Considerations

While the core Robot Power and Signal cables are standard, many IRB 6700 applications utilize ABB's integrated hose and cable packages like DressPack or SpotPack. These packages streamline the routing of utilities needed for specific applications (e.g., spot welding, material handling with complex grippers) along the robot arm.

What it Contains

DressPack typically includes conduits for customer-supplied power cables, signal/communication lines, and pneumatic/hydraulic hoses needed by the end effector or tooling.

Electrical Integration

Electrically, the cables within the DressPack are essentially a structured form of "Customer Cables." They connect the tooling/sensors on the robot's tool flange back to specific interface points, often near the robot base or axis 3, and ultimately route back to the IRC5 controller's I/O or power modules.

Dedicated Manual

Because DressPack configurations can vary significantly based on the application package ordered (e.g., material handling, spot welding), it has its own dedicated Product Manual (3HAC044270-001 as listed on page 10). This manual is the primary source for understanding:

Specific connection points for DressPack cables/hoses at the robot base and tool flange.
Routing instructions along the robot arm.
Maintenance procedures specific to the DressPack components.

Connection Philosophy: Think of DressPack as a highly organized pathway for your application-specific customer connections, ensuring they move reliably with the robot arm without snagging or excessive wear.

Connector Integrity and Pinouts: The Devil's in the Details

The manual specifies the primary connection points (e.g., R1.MP, R1.SMB, XS1, XS2). While these use robust industrial connectors designed for reliability, proper handling and verification are essential.

Handling

Connectors, especially multi-pin signal connectors, should be handled with care. Avoid dropping them or forcing connections. Bent pins or damaged housings can lead to intermittent or total connection failure. The manual highlights this risk for cable packs (page 20).

Pinouts are King

Never assume pin assignments. While connectors might look standard, the specific pinout (which signal or power line goes to which pin) is critical. Always refer to the official ABB Circuit Diagrams (Document 3HAC043446-005 for IRB 6700, as listed on page 10) for definitive pin assignments.

Cleanliness

Keep connectors clean and free from dirt, oil, or moisture, which can impede conductivity or cause short circuits over time.

Shielding and Signal Integrity

The Robot Signal Cable (connecting R1.SMB to XS2) is specified as a shielded cable (page 96).

Why Shielding Matters

Industrial environments often have significant electromagnetic interference (EMI) from motors, drives, welding equipment, etc. This EMI can corrupt the low-voltage feedback signals traveling from the robot's SMB to the controller if the cable isn't properly shielded.

Impact of Noise

Corrupted signals can lead to various issues, including inaccurate positioning, false error messages, or even unexpected robot stops.

Best Practice

Always use the specified shielded cables from ABB for signal connections. Ensure the shield is properly terminated (grounded) at the controller end as detailed in the circuit diagrams and controller manual. Avoid running signal cables parallel to high-power cables for long distances if possible.

Safety First: Connecting Power

Safety Warnings

Reiterating the safety warnings from the manual (pages 25, 46):

Power Off:
Before connecting or disconnecting any cables, especially the main Robot Power Cable (R1.MP), ensure the main power to the IRC5 controller is switched off and locked out/tagged out according to your facility's safety procedures.
Stored Energy:
Be aware that the IRC5 controller contains capacitors that can hold a charge even after power is switched off (page 25). Allow sufficient discharge time as specified in the controller manual before working inside the cabinet.
External Power:
Remember that customer-supplied power to tooling or auxiliary equipment might remain live even if the robot controller is off (page 25). Ensure all relevant power sources are de-energized.

Controller Variations

While the robot-side connectors (R1.MP, R1.SMB) are standard for the IRB 6700, the exact location and labeling of the corresponding connectors (XS1, XS2) and customer connection interfaces on the IRC5 controller might differ slightly based on:

Cabinet Type

Single Cabinet IRC5
Dual Cabinet IRC5
Compact IRC5

Option Boards

The specific I/O boards (e.g., DeviceNet, Profibus, digital/analog I/O) installed in the controller.

Important Note

Always cross-reference with the specific Product Manual and Circuit Diagrams for your IRC5 controller configuration.

Best Practices for Reliable Connections

Secure Mating

Ensure all connectors (both robot and customer cables) are fully seated and secured (e.g., locking rings tightened). Loose connections are a common source of faults.

Cable Routing

Plan cable paths carefully. Avoid sharp bends, pinch points, or routing cables where they might be subject to excessive wear, heat, or chemical exposure. Use appropriate cable conduits or protection where necessary.

Strain Relief

Implement proper strain relief at both the controller and robot ends to prevent cable stress or damage at the connector points, especially for cables that move with the robot arm (like DressPack components).

Grounding

Ensure all necessary protective earth (PE) connections are correctly installed for safety, particularly when dealing with customer-supplied power.

Critical Configuration: Defining Robot Loads (Payload & Tool Data)

The manual mentions checking load diagrams and permitted extra loads (page 86, 87). However, simply knowing the maximum payload isn't enough. Accurately defining the properties of the tool (end effector/gripper) and the workpiece(s) it handles within the IRC5 controller software is absolutely critical for performance, longevity, and safety.

Why It's Crucial

Path Accuracy:
The robot controller uses the defined load data to calculate the dynamic forces acting on the robot structure. Incorrect data leads to inaccurate path following, especially at higher speeds or during complex movements.
Cycle Time & Performance:
Optimized motion planning relies on accurate load data. Incorrect definitions might force the controller to use more conservative (slower) movement profiles or lead to oscillations.

Component Wear:
Consistently operating with incorrectly defined (especially underestimated) loads puts excessive strain on motors, gears, and mechanical structures, leading to premature wear and potential failures.
Safety & Stability:
Grossly incorrect load data, particularly regarding the center of gravity, could potentially lead to unexpected movements or instability in certain poses.

What Needs Definition (Beyond just weight)

Mass

The weight (in kg) of the tool and the payload.

Center of Gravity (CoG)

The X, Y, and Z coordinates of the tool's and payload's center of gravity relative to the tool flange (Axis 6 mounting face).

Moments of Inertia

How the mass is distributed around the center of gravity (Ix, Iy, Iz). This affects how the robot responds to rotational movements.

Practical Steps & Tips

Use Accurate Data:
Whenever possible, use CAD data for your tooling and payload to calculate mass, CoG, and moments of inertia accurately.
ABB Tools:
ABB offers tools (like RobotStudio) that can help estimate or calculate load data based on geometry.
LoadIdentify Routine:
The IRC5 controller often includes a "LoadIdentify" routine which can help the robot automatically estimate the load characteristics through a series of controlled movements.
Multiple Payloads:
Define all payload variants the robot handles (e.g., gripper empty, gripper with part A, gripper with part B) and ensure the robot program selects the correct payload data before executing movements.

Defining Boundaries: Working Range and Mechanical Stops

The manual details the standard working range of each axis (page 55) and the procedure for installing optional mechanical stops, particularly for Axis 1 (pages 93-95). Understanding these limitations is vital for safe and efficient cell design.

Software vs. Hardware Limits

Software Limits:
These are parameter settings within the IRC5 controller that define the permissible movement range for each axis. They are the primary means of restricting motion during normal operation.
Mechanical Stops (Hardware):
These are physical blocks that prevent the robot axis from moving beyond a certain point. They act as a crucial safety backup if software limits fail or during specific non-operational scenarios.

Why Restrict the Range?

Collision Avoidance:
The most common reason is to prevent the robot arm from colliding with peripheral equipment, safety fences, building structures, or other robots within the workspace.
Process Constraints:
Sometimes the specific application requires the robot to operate only within a subset of its full reach.
Safety Zoning:
Limiting the swing of Axis 1, for example, can help define safer zones for human interaction or maintenance access around the robot base.

Implementing Restrictions

Planning: Determine required restrictions during the cell design phase based on reach studies and collision analysis (e.g., using RobotStudio).
Mechanical Stops (Axis 1): If hardware restriction is needed for Axis 1, the optional stops (page 94) must be physically installed. Crucially, after installing mechanical stops, the corresponding software parameters must be adjusted to match (page 95). Failure to do so will result in the robot attempting to move beyond the physical stop, causing errors and potential damage.
Software Limits: Adjust the Upper joint bound and Lower joint bound system parameters for the relevant axes in the controller configuration.
Recalibration: Changing mechanical stops or significant software limits might necessitate recalibration checks, especially if Absolute Accuracy is critical.

LeanID Considerations (Axis 5 & 6)

The manual notes specific working range differences for robots equipped with the LeanID DressPack option (page 55). The integrated design might slightly alter the rotational limits compared to standard models. Always verify the correct range based on your specific robot variant and options.