The Allen-Bradley Guardmaster GuardShield is offered as a Type 2 and a Type 4 POC safety light curtain as well as a Type 4 PAC safety light curtain. The Type 4 POC GuardShield is offered in both 14 mm and 30 mm resolutions while the Type 2 is offered in 30 mm resolution only. The GuardShield PAC is offered with multiple beam configurations with varying beam spacings. All GuardShield family safety light curtains meet the requirements of IEC/EN 61496.

POC safety light curtains are designed to detect the presence of an opaque object of a minimum resolution. These devices are usually positioned in front of the point of operation hazard, however, they may also be used for perimeter guarding applications.

PAC safety light curtains are typically used as opto-electronic fences or as whole body detection devices to detect personnel or large objects when they pass through the sensing field. These PAC safety light curtains are typically positioned around an area or in front of a process entry or exit area.

The Allen-Bradley Guardmaster GuardShield is a two-box safety light curtain, consisting of a nonmatched transmitter and receiver pair. Any GuardShield transmitter of the same family (POC, PAC) and same resolution will work with any receiver of the same family and resolution. The synchronization between transmitter and receiver is achieved optically. The first beam adjacent to the receiver LEDs is the synchronization channel. This synchronization beam cannot be blocked in a fixed or floating blanking application