ABB JOKAB SAFETY Pluto series safety PLC

Single channel secure input function

Dual hand control function

Bypass function

Shielding lamp control function

Safe absolute value encoder function

Electronic cam function

6. Safety encoder and positioning monitoring

6.1 Safety Absolute Value Encoder

Pluto can be connected to a dedicated secure absolute value encoder for secure position and velocity monitoring. The encoder is directly connected to the Pluto safety bus and supports:

Single cycle encoder (RSA 597): 13 bit resolution, 8192 positions/cycle

Multi turn encoder (RSA 698): 25 bit total resolution (13 bits/turn+12 turns)

Hollow shaft encoder (RHA 597/698): suitable for direct installation on the motor shaft

6.2 Function Block Support

Pluto Manager provides specialized functional blocks for processing encoder signals:

Safe Encoder: Process two single loop encoders to generate safe position and velocity values

Safe Encoder Multiturn: Process two multi turn encoders to generate safe position and velocity values

Encoder Cam: Electronic cam function that activates output within a specific position range

6.3 Application Scenarios

Security encoders are widely used in:

Longmen robot position monitoring

Industrial robot safety zone restrictions

Eccentric press electronic cam

Overspeed monitoring

Static state monitoring

7. Application case: Robot unit safety system

The document provides a complete example of a robot unit safety system, demonstrating the application of Pluto in multi device collaboration.

7.1 System Architecture

Pluto 0 (robot unit): Connect emergency stop button, unit door lock sensor, reset button

Pluto 1 (machining machine): Connect machine emergency stop, protective door lock sensor, reset button

Two Pluto devices are interconnected through a secure bus and share status information

7.2 Safety Features

Emergency stop priority: When the emergency stop button is triggered, both the robot and the machine stop simultaneously

Partition control: When the machine tool protective door is closed, the robot and machine tool are divided into two independent safety zones; When the machine tool protective door is opened, it merges into one safety zone

Reset management: After the door is opened, the system must be reset through the reset button outside the door to prevent accidental startup

7.3 Global Variable Communication

The Pluto system supports global variables (GM) for sharing security states between different Pluto units:

GM0.0 (Pluto 0): Emergency stop status is normal

GM1.0 (Pluto 1): Emergency stop status is normal

GM1.1 (Pluto 1): Machine tool protective door closed

Through global variables, each Pluto can obtain the status of other units and make local decisions based on it.