10.3 Typical Installation
The safety system is based on the use of an infrared light curtain as a barrier between the operator and the dangerously high voltages present on the transformer under test.
A typical system is shown below:

The light curtain is positioned in front of the tester. It extends well beyond the width of the tester so that the operator is not impeded when he/she has to load and unload the transformer under test.
The infrared safety system is housed in three separate modules:
- A vertical column of transmitters and/or receivers, which form the left-hand edge of the light curtain.
- A vertical column of transmitters and/or receivers, which form the righthand edge of the light curtain.
- A control box, containing the power supply circuits, the switching electronics and the interface to the tester.
The interconnection between each of the modules is via simple multi-way cables, which are easy to install.
The following show plan and side views of a typical installation:
The dimensions are as follows:
- Width of the light curtain: 1.8m to 2.0m
- Cable length from control box to vertical columns: 2m
- Cable length from control box to tester: 1.5m
- Lowest beam in light curtain: 60mm
maximum above the work surface
- Highest beam in light curtain: 630mm
minimum above the work surface
- Maximum object resolution: 18mm