Interlocking guards

Incorporate safety devices (fixed guards, interlocks). 

Warning labels used where guarding, interlocks, or other fail-safe measures required ... 

Protection against direct contact with live parts is fulfilled in a number of ways, such as enclosures, guards, interlocks, insulation, and the use of SELV or PELV circuits. 

User protection is paramount Warnings are only permitted when no other means are possible and may not take the place of a safe design. For example, a MOVING PARTS WARNING is allowed only when the hazard is directly involved in the production process and there are no other possible options (i.e., guards, interlocks, stop-switch, sensors). Therefore, if a guard or other protection means is possible, it must be employed. 

A form of guard that has a movable part connected with the machinery so that the parts of the machine causing a hazard cannot be set in motion until the guard is in place. Before the guard can be opened sufficiently to allow access to the work area, the power is turned off and the motion is braked to prevent potential injuries to workers. It may also be called Interlocked Barrier Guard. See also Barrier Guard Interlock Machine Guarding. 

A. Material handling and storage B. Machine guarding, interlocks and controls C. Health and hygiene D. Fire protection E. Other standards 15 ... 

Has all access to dangerous moving parts, or danger zones created by the equipment, been prevented by the provision of the correct guards, interlocks (both safety non-safety) and/or barriers ... 

Fig. 13.7 Positive and negative mode limit switches used in guard interlocking.

Whilst we are considering relay based systems its is important to be aware of the wide range of applications and devices in relays applied to machinery safety systems. In simple applications such as emergency stops and guard interlocks the safety integrity of the protection system depends very often on a single relay or a pair of relays and a pair of field contacts. 

Never operate any conveyor unless all safety guards, interlocks, guards, covers, maintenance panels, and warning devices are in place. 

Removing or making safety devices inoperative. When guards, interlocks, and other safety devices are bypassed, removed, or made inoperative, injuries can easily occur. Any activity such as this must be regarded as a serious safety infraction. 

INDUSTRIAL SAFETY PROVISIONS. In the design of the APE and associated operational shield, conventional machine design practices are used to protect operators from hazards associated with moving parts. Proper techniques for guarding of hazardous machine areas are used, including the use of interlocks In the control system to prevent movements until certain conditions are satisfied, or to stop movements In emergency situations... 

Guarding and interlocking of mechanical and other equipment where appropriate... 

In addition to the machine guarding, the control system should be interlocked with an electronically monitored failsafe system. The control software should have an awareness of the position and action of all moving parts and measurement devices. Therefore, if an unplanned incident or out-of-protocol action does occur, the system will take action or stop action to minimize the likelihood of additional safety hazards. In some cases, as with system calibration or super user access, graded access levels can be custom-built into the design for specialized and infrequent operations. 

Interlocked Guards—Shut down the machine when the guard is not securely in place or is disengaged. 

Subsequently. The press was brought up-to-date with respect to ANSI B65.5 wire mesh guarding was extended to prevent access to the side of press from the operations area (the wire mesh guarding has an electronically interlocked entry door in the rear) the control panel was moved to the front of the press to ensure clear and unobstructed vision of the entire platen area the safety control circuit was upgraded to require specific resetting, once the stop switch on the safety bar on the platen had been actuated the press was adjusted to operate in the timed mode with a minimum cycle limit of 10 seconds the job description was revised to include instmctions on removing debris safety mats were installed to prevent access to the platen area from the sides of the platen and training was improved. 

Larger lathes are best fitted with sliding shield guards shown in Fig. 9.9. These are made from high-quality steel with a polycarbonate window to provide maximum operator protection from chuck, swarf and coolant and provide excellent visibUity. The guard slides over the head-stock and out of the way when access to the chuck or tooling is required. These can also be fitted with an electrical safety interlock to prevent the... 

For the purpose of ensuring that health and safety conditions are maintained, every power press is thoroughly examined at least every 12 months where it has fixed guards, and at least every 6 months in other cases (e.g. interlocked guarding or automatic guarding). 

Safety of Machinery—Interlocking devices associated with guards Safety of Machinery—Safety related parts of control systems—General principals... 

Description of the safeguards, interacting functions, and interlocking of guards for hazardous movements and... 

We have the products, a complete line of curtains, interlocked GUARDS, enclosures and containment products. 

Mechanical Guard with electrical or magnetic interlock... 

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