When first exposed to  the LSS-2380 series interlock system, many people immediately assume that the system uses some sort of complicated communication protocol between all modules.  This is not the case.

Laser Safety Systems has simply taken the circuitry that would normally be contained in a bulky wall-mounted enclosure and spread it out amongst multiple smaller modules while carrying the vital control lines (set, unset, power, ground, align, etc.) along the 8 conductors that run from module to module.  With the modules in a series chain, any location in the chain can control (or be controlled by) the state of the 8 conductors.

All critical function relays in the system are Shrack SR2M safety relays with forcibly guided contact sets.  These relays are approved for use in critical safety circuits in elevators, emergency machine shut-off, light barrier controls, etc.

MTBF lifetime examples:

Push-to-arm & Push-to-disarm switches used on the LSS-2381 module: >1 million operations.

All Crash switches:  >50,000 cycles

Push-to-exit switch:  >1 million operations

Microprocessors (running the Access Control and Warning modules) > 1 million hours.

Relay endurance - 10 million cycles

There are no incandescent bulbs in the system.  All lighting is solid state LED with a lifetime rated  > 100,000 hours     

(That's 8 hours per day for 34 years.)