Safety Devices
Machine Access
Personnel are protected from the work area of the cell with a combination of safety features including fencing, interlocked safety gates, and guards.
The fencing and its associated interlocking are provided to protect the operator and other persons from the following hazards:
- Robot working zones
- Welding operations
- Failure of energy supplies
Failure to properly operate and maintain the cells safety features will increase risk of injury to the operator and all other persons adjacent to the machine.
Access to the cell components is limited due to fencing, guarding, etc. As such, special precautions must be taken when entering the cell to access the equipment.
- Remove guarding only when necessary.
- Replace all guarding completely before returning machine to production.
- Repair or replace any defects before restarting machine.
- Never defeat safety devices and guards.
Follow Lockout / Tagout (LOTO) before removing guarding to work on the system.
Never operate this machine unless all guarding is in place and undamaged.
Ensure that guarding is handled properly. When servicing machine, ensure guarding is placed in a safe place, away from moving parts.
Disregarding these safety precautions can result in machine damage, injury, or death.
Safety Gates
Use normal shutdown procedures to stop the machine and lockout the gate being accessed before entering a safety gate. Lockout any applicable energy sources before performing any work within the gated area.
When a safety gate has been opened, it can be locked out by placing the lockout device through the sliding handle to prevent the handle pin from sliding back into the receiver. If more than one person is to enter the cell, each person must place a locking device on the gate handle. Lock out the safety gate BEFORE entering into the cell.
Emergency Stops (E-Stop)
Emergency Stop (E-Stop) buttons, when pressed, shut down the entire cell for safety purposes. The E-Stops are located on the MOP, Robot FlexPendants, fencing, and safety gate.
Main Disconnect
The Main Disconnect Switch is located on the Power Distribution Panel (PDP). To remove main power from the machine, open the main electrical disconnect switch following the proper Lockout / Tagout (LOTO) procedures including arc flash safety and apply a personal lock.
If more than one person is to perform work on the machine, each employee must place a personal lock on the energy source using a multiple lockout device (scissor lock). The main electrical disconnect will shut off the main power to the operation. Verify power is removed by indication on the Main Operator Panel (MOP) screen and attempt to start the machine before beginning maintenance.
Placing the Main Disconnect into the Off position will NOT remove power from any interlocking device nor will it remove any power supplied by auxiliary voltages such as the lighting transformer (line side circuits above the main disconnect).
PLC Lighting Rotary Disconnect Switch
The Programmable Log Controller (PLC) electrical power circuits that are wired above the main electrical disconnect are not de-energized by the main disconnect switch. The PLC Lighting Rotary Disconnect switch (also known as E-2, or Hot Power), is located inside the Power Distribution Panel. The PLC Lighting Rotary Disconnect switch controls the power to 120VAC Power Supply circuits, powering the operation lighting and PLC. The PLC Lighting Rotary Disconnect switch features provisions for placing a personal padlock to lock out and prevent personnel from switching the power back to the "ON" position.
Before performing any maintenance or repair work, ensure to follow all Lockout / Tagout (LOTO) procedures.
VFD Controller
The Variable Frequency Drive (VFD) Disconnect switch is located on the Weiss VFD Control Panel. To remove power from the turntable, open the Weiss VFD electrical disconnect switch following the proper Lockout / Tagout (LOTO) procedures including arc flash safety and apply a personal lock.
If more than one person is to perform work on the machine, each employee must place a personal lock on the energy source using a multiple lockout device (scissor lock). The VFD electrical disconnect will shut off the power to the turntable and its drive system. Verify power is removed by indication on the Main Operaotr Panel (MOP) screen and attempt to operate the turntable. The turntable must not be able to move.
Robot Controllers
The ABB IRC5 Robot Controller Main Disconnect switch is located on the ABB IRC5 Robot Controller. Each robot controller features a Main Disconnect Switch. There are four (4) located in this cell, each controlling a specific ABB robot. To remove power from a robot, place the electrical disconnect in the "OFF" position following the proper Lockout / Tagout (LOTO) procedures including arc flash safety and apply a personal lock.
Weld Controllers
The ABB Weld Controller Disconnect switches are located on the ABB Weld Controllers, each located above the ABB Robot Controllers. There are four (4) located in this cell, each controlling the spot weld guns on a different ABB robot.
To remove power from a robot spot welder, place the electrical disconnect in the "OFF" position following the proper Lockout / Tagout (LOTO procedures including arc flash safety and apply a personal lock.
Light Screens
Safety light screens, or light curtains are used in front of the turntable. Safety light screens protect personnel from injury and machines from damage by guarding points of operation, access, areas, and perimeters. Banner EZ-SCREEN is a two-piece ("two-box") system - comprising an emitter and a receiver. Emitters have a row of synchronized modulated infrared (invisible) Light Emitting Diodes (LEDs) in a compact rectangular metal housing. Receivers have a corresponding row of synchronized photo-detectors. The dimensions of the light screen created by the emitter and receiver are called the "defined area"; its width and height are determined by the length of the sensor pair and the distance between them.
In typical operation, if any part of an operator's (or any opaque objects) of more than a pre-determined cross section is detected, the Output Signal Switching Device (OSSD) solid-state safety outputs will turn off. These safety outputs are connected to the guarded machine's Final Switching Devices (FSDs) that control the Machine Primary Control Elements (MPCEs), which immediately stop the motion of the guarded machine.
Safety Mats
Safety mats are used on the sides of the turntable to allow operators to access the turntable safely. Safety mats protect personnel from injury and machines from damage by guarding points of operation, access, areas, and perimeters. The machine cannot operator while personnel are on a safety mat, similar to the light screens when an operator is detected.
Tip Dressers
The ABB Tip Dresser Disconnect switches are located next to each of their associated ABB IB 6700 Robots. There are four (4) located in this cell, each controlling power to the specific ABB Tip Dresser. Power should always be removed from the specific tip dresser before doing any maintenance on or around the tip dresser.
To remove power from a robot tip dresser, place the electrical disconnect in the "OFF" position following the proper lockout/tagout (LOTO) procedures and apply a personal lock.
The operating handle may be padlocked in the Off position with up to three (3) padlocks. When locked, the enclosure door is interlocked and can not be opened. All padlocks must be removed to gain entry to the enclosure.
Cap Changers
The Brauer Systemtechnik Cap Changer Disconnect switches are located next to each of their associated ABB IB 6700 Robots. There are four (4) located in this cell, each controlling power to the specific Brauer Tip Changer. Power should always be removed from the specific tip changer before doing any maintenance on or around the tip changer.
To remove power from a robot tip changer, place the electrical disconnect in the "OFF" position following the proper Lockout / Tagout (LOTO) procedures and apply a personal lock.
Main Air
The main air lockout valve is located on the fencing. Turn the main air supply manual shut off valve to the "OFF" position and apply a padlock following all Lockout / Tagout (LOTO) procedures. Verify there is a zero pressure reading on the air pressure gauge before starting any maintenance work on the air system or machine.
Some pneumatic circuits trap air. Check the pneumatic drawings for any possible trapped air circuits and relieve any trapped air before performing any maintenance on the system.
Ancillary Air
The ancillary equipment has individual shutoff valves allowing for pneumatic shutoff for a specific piece of equipment without removing air from the entire cell. Each of this shutoff valves are found in different locations throughout the cell.
The turntable shutoff is located on the fencing, near the main air shutoff. Each robot has an air shutoff located on the sides of the individual robot controllers. Turn the ancillary air supply manual shut off valve to the "OFF" position and apply a padlock, following all Lockout / Tagout (LOTO) procedures. Verify there is a zero pressure reading on the air pressure gauge before starting any maintenance work on the the specific equipment.
Before locking out the air supply, secure any machine parts that could move when the air pressure is removed.
Water Shut-Offs
There are four (4) ball valves that control the main water system to the cell. These four (4) valves are for "Plant Water Out", "Plant Water In", "To Header", and "From Header". Closing these ball valves will remove water from any of these four systems.
Each of the four (4) Robot Weld Controllers also have two (2) ball valves that control water to and from the header.
When doing maintenance on the robots and any of their associated equipment, close the water valves to stop water pressure to the equipment.
Fencing
When the machine is in operation, all safety guards must be in place on the equipment and safety gates and doors closed and latched. There is one (1) interlocked safety gate located near the robot controllers on this cell as shown in the figure. All fencing must be undamaged and in place before operating machinery.
There are also sets of light screens located in the front of the machine by the turntable. The light screens must be clear before the machine can be placed in automatic mode.