Banner Safety Controller

This page provides detailed information about the Banner Safety Controller that comes pre-installed in the Sawyer Controller. 

Contents

• Contents
• Introduction
• Warnings
• Wiring
• Low Power Mode
• Banner Retrofit Kit
• Performing a Risk Assessment
• Specifications

Introduction

The Sawyer robot controller is supervised by a safety system comprised of a custom and preconfigured Banner Safety Controller and associated wiring. The safety controller provides safety-rated E-Stop functionality, and provides support for safety-rated safeguarding solutions for those applications that require them. The control systems monitors a variety of input devices such as e-stop buttons, safety mats, inter-locked guards, etc. and will limit or disconnect the voltage being supplied to the robot motors.

• User Guide Banner Safety Controller SC26-2evm

• SC26-2evm
• Bus Monitor input monitors redundant analog DC voltage inputs to determine if the voltage is greater than or less than a preset level
• Upper and lower thresholds are independently selectable from 7 V dc to 14 V dc, in 0.25 V dc increments
• Bus Monitor Input can be used in applications up to Cat 4/PLe and/or SIL3
• The value of the monitored voltage is accessible via the Ethernet interface

Warnings

• All safety related signals shall be constructed redundantly (i.e. two independent channels). In order to prevent a single fault from leading to loss of a safety function, the two channels must be kept separate.
• Always connect safety related signals to safety related devices with the correct functional safety performance level. Failure to follow this practice will result in a compromised safety system that will not achieve the level of protection required for the application per the risk assessment.

Wiring

The Banner Safety Controller is customer-accessible for customers who may want to attach other safety devices. It is also configurable, so customers can configure the desired behavior, if not already supported via the standard configuration provided by Rethink Robotics and documented here.

The wiring diagrams below illustrate how the Banner safety system is wired. These diagrams can be referenced when attaching additional devices.

Low Power Mode

Sawyer is designed as a power and force limited robot by inherent design, but customers can choose to further limit the capabilities of the robot by further limiting the power available to the robot in such a way that limits the maximum speed at which it can run. This is done by operating Sawyer in Low Power Mode.

The Banner Safety Controller found inside the Controller has been customized to monitor the voltage of the power going to Sawyer's arm. To place Sawyer in Low Power mode, jumper the Low Voltage Enable signal before powering up the robot (see the schematic below for the wiring diagram). The robot’s maximum speed will be limited to approximately half that of normal operation.

If, at some point, the Banner Safety Controller senses the robot operating at normal power mode when the wiring is configured for low power mode, the motor power relay will be opened, cutting power to the motors in the arm, and a safety violation error will be reported.

Low Power Mode in the Intera UI

When the Banner Safety Controller has been set up properly for low power mode, you will see the highlighted feedback in the UI in both the Robot Screen and Intera Studio.

Low Power and ClickSmart Tools

When the robot is being used in Low Power mode, please review the ClickSmart Gripper Kits Low Power Mode considerations for proper ClickSmart tool functionality

Banner Retrofit Kit

All Robots built after March 2017 will come with additional Hardware and Software that allows for safety rated devices, such as laser scanners, light curtains, safety mats and enabling devices to be connected to the Banner Safety Controller installed in the Sawyer Controller.

This addition is not required for all applications. For users with Pre- April 2017 Robots an install kit is available for purchase for interested parties. 

Performing a Risk Assessment

RIA TR R15.306:2014 provides a detailed methodology for performing risk assessments. For Power and Force Limited collaborative robots, ISO TS 15066 and ANSI R15.06/ISO 10218-2 provide guidance on the right aspects to be evaluating. It is important to evaluate the entire robotic application including not just the robot itself, but all tools, fixtures, parts, end effectors, machinery, etc within the robotic cell. Once all hazards in normal operation, including capturing both intended operation and interaction situations as well as unintended, foreseeable misuse situations, the hazards should be scored on probability of exposure, severity of injury hazard, frequency of exposure, and avoid-ability.

After determining the hazards and their risks, the standards require users to attempt to eliminate or reduce them to acceptable levels. There is a hierarchy of steps to consider starting with elimination of hazards at the top to the use of personal protective equipment as the last level. After applying any changes to the work cell to eliminate or mitigate the hazards, each hazard risk is re-scored to determine a final risk level and show the work cell meets the desired level of risk.

In the absence of specific limits or standardized, repeatable, precise force/pressure measuring techniques, customers are testing the robot’s performance with respect to these hazards and determining the injury severity risk using common sense. In situations where either the part being handled presents a risk or some equipment in the collaborative work cell presents a hazard, some customers are choosing to add protective measures that slow, pause or stop the robot when something is detected within proximity of the robot or the machine it is tending.

Specifications

Safety

Sawyer Safety System Performance (incl. Banner Safety Controller, contactors, etc): Category 3, PL d (EN ISO 13849) SIL CL 2 (IEC 62061, IEC 61508)

Banner Safety Controller certified suitable for use applications up to Category 4, PL e (EN ISO 13849) SIL CL 3 (IEC 62061, IEC 61508)

Product Performance Standards

See Standards and Regulations section in the Instruction Manual for a list of industry applicable U.S. and international standards.

EMC

Meets or exceeds all EMC requirements in IEC 61131-2, IEC 62061 Annex E, Table E.1 (increased immunity levels), IEC 61326-1:2006, and IEC61326-3-1:2008

Convertible I/O

• Sourcing current: 80 mA maximum (overcurrent protected)

Test Pulse

• Width: 200 μs max.
• Rate: 200 ms typical

Certifications

• IEC 61508 Parts 1-7:2010
• IEC 62061:2015
• ISO 13849-1:2006 + TC 1:2009
• IEC 61131-2:2007
• IEC 60204-1:2009 (in extracts)
• IEC 61784-3:2010 (in extracts)
• EN 574:1996 + A1:2008 (in extracts)

Removable Screw Terminals

• Wire size: 24 to 12 AWG (0.2 to 3.31 mm²)
• Wire strip length: 7 to 8 mm (0.275 in to 0.315 in)
• Tightening torque: 0.565 N·m (5.0 in-lb)

Removable Clamp Terminals

• Important:Clamp terminals are designed for 1 wire only. If more than 1 wire is connected to a terminal, a wire could loosen or become completely disconnected from the terminal, causing a short.
• Wire size: 24 to 16 AWG (0.20 to 1.31 mm²)
• Wire strip length: 8.00 mm (0.315 in)

Safety Inputs (and Convertible I/O when used as inputs)

• Input On threshold: > 15 V dc (guaranteed on), 30 V dc max.
• Input Off threshold: < 5 V dc and < 2 mA, –3 V dc min.
• Input On current: 5 mA typical at 24 V dc, 50 mA peak contact cleaning current at 24 V dc
• Input lead resistance: 300 Ω max. (150 Ω per lead)
• Input requirements for a 4-wire Safety Mat:
• Max. capacity between plates: 0.22 μF
• Max. capacity between bottom plate and ground: 0.22 μF
• Max. resistance between the 2 input terminals of one plate: 20 Ω

Solid State Safety Outputs

0.5 A max. at 24 V dc (1.0 V dc max. drop), 1 A max. inrush

• Output OFF threshold: 1.7 V dc typical (2.0 V dc max.)
• Output leakage current: 50 μA max. with open 0 V
• Load: 0.1 μF max., 1 H max., 10 Ω max. per lead

Response Recovery Times

• Input to Output Response Time (Input Stop to Output Off): see the Configuration Summary in the PC Interface, as it can vary
• Input Recover Time (Stop to Run): Dependent on configuration
• Safety Output SO..a to SO..b turn On differential (used as a pair, not split): 6 to 14 ms typical, ±25 ms maximum
• Output SOx to Output SOy turn on Differential (same input, same delay): 3 scan times +25 ms max.
• Safety Output On/Off Delay Tolerance: ±3%

Output Protection

• All solid-state outputs (safety and non-safety) are protected from shorts to 0 V or +24 V, including overcurrent conditions

Current Feature ID

• SC26-2evm