PLC自检信号很多，内部器件也很多，多数使用者未充分发挥其作用。其实，完全可利用它进行PLC自身工作的监控，或对控制对象进行监控。对一个复杂的控制系统，特别是自动控制系统，监控以至进一步能自诊断是非常必要的，它可减少系统的故障，出了故障也好查找，可提高累计平均无故障运行时间，降低故障修复时间，提高系统的可靠性。
Wild Heerbrugg Falconar 1.4/98mm #449
Wild Heerbrugg AVIOLYT BC2 Analytical Spot Map Plotter
Wild Heerbrugg M7A StereoZoom w/Ring Light & Stand
Wild Heerbrugg M7A StereoZoom w/Ring Light & Stand
HV# Wild Heerbrugg makrozoom 1:5
Leica DIOR 3002S Wild Heerbrugg Surveyor Prismless
Wild Heerbrugg T2 Theodolite 1" Erect Image Late Ver.
Wild Heerbrugg BC4 Astrocamera Astrograph Telescope
Wild Heerbrugg Aerial Camera Aviotar 4/210mm (180x180)
Wild Heerbrugg T2000S Theodolite - MINT
Wild Heerbrugg T1 New Style Optical Vernier Theodolite
Wild Heerbrugg Theodolite Laser System - Excellent
WILD HEERBRUGG T-16 T16 THEODOLITE UPRIGHT IMAGE EX CON
WILD Heerbrugg T16 Theodolite made in Switzerland
