What can't your safety laser scanner do?

Due to the large amount of safety laser scanners on the market, it is easy to get lost during the product selection process. There are many choices depending on application requirements; communication protocol, protective field range, safety resolution and many more. With all the available options this can make the proper selection difficult.

I recently worked on an RFQ from a machine builder requiring a safety laser scanner for a protective field of 4 ft x 15 ft. The machine builder was interested in the Leuze electronic RSL400 compared to a product he was using on other applications. To select the proper RSL400 model I asked a couple of important and pertinent questions:

1. What is the required mounting height of the scanner for the application?

The application required that the scanner be mounted 6 inches above the floor. As indicated by ISO 13855 the minimum resolution required for a scanner mounted at this height is 60mm. The product previously used by the OEM was only capable of a 10 ft protective field of at 60mm resolution, so two (2) units would be required for the application. The RSL410-x provides a maximum protective field of 27 ft at 60mm resolution so that only one (1) unit would be required.

2. What is the required response time of the scanner for the application?

This is a key question for determining the safety distance of an Optoelectronic safety device (i.e. laser scanner, light curtain). The higher the response time the more distance or floor space required between an operator and the danger zone. In this case, both the scanners had a similar response time.

3. How many fields/zones are required for the application (simple or complex)?

The number of protective and warning fields are a real concern for applications such as a static robotic cell with a load/unload area or an AGV. Since this was a very simple application, the number of required fields were of no real consequence as both products were sufficient (1 protective field without a warning field). Some applications, however, require two (or more) protective functions, and multiple warning fields which would then require a higher-end model.

In summary, the application is what drives the product choice, the product does not drive the application. The more accurate the information the more precise the product selection/solution eliminating issues and redesign later.