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Interlocks and light guards

To complement our market-leading machine guarding we also supply interlocks, light guards, pressure-sensitive mats and other safety devices, either to the customer’s specification or we can make recommendations. Where appropriate we can supply machine guards with interlocks preinstalled, ready to be connected to the machine’s safety-related control system.

How and where interlocks and light guards should be used

Interlocks, light guards and other safety devices play a critical part in machine guarding, depending on the nature of the machine and the hazards being safeguarded. Essentially, interlocks and light guards disable the machine when they are actuated. For example, a simple interlock might be located on a gate that allows access to the machine. If the machine had not been stopped prior to the gate opening, then the action of opening the gate and activating the interlock circuit would immediately disable the machine and make access safe (if the machine takes time to stop after it has been isolated from the power source, then it may be necessary for the interlock to incorporate a lock to prevent the gate from opening until the hazardous movement has stopped).

A light guard works in the same way, in that the machine is disabled when the light beam is broken. However, a light guard would more typically be used on machinery such a press brake where a physical guard would be impractical but access to the machine during operation would be dangerous. Furthermore, light guards can only be used where there is not a risk of hazardous emissions or parts being ejected from the machine.

Interlock mounting options

We can install interlock mounting brackets on the machine guards for customers to fit their own switches, or we can mount any type of switches free-issued to us by the customer. Alternatively, we can source and install switches specified by the customer, or we can install switches that we have selected to suit the application.

Electrical interface work

If interlocks and/or light guards form part of a machine guard that we are installing, our electricians can connect these to the machine’s safety-related control system. In addition, we can supply and install trunking or cable ducting at the same time.

Electrical installations comply with the requirements in BS EN ISO 13849-1 or BS EN 62061. Members of our electrical installation team are also certified to the current IEE 17th edition regulations. Risk assessments and method statements covering the electrical installation work can be provided on request.