描述
PLC的通信包括PLC与PLC、PLC与上位计算机、PLC与其它智能设备之间的通信，PLC系统与通用计算机可直接或通过通信处理单元、通信转换单元相连构成网络，以实现信息的交换，并可构成“集中管理、分散控制”的多级分布式控制系统，满足工厂自动化（FA）系统发展的需要。
Rodenstock 58mm 5.6 Graflex Grandagon-Super Wide-Angle
Rodenstock Grandagon-N 90mm f/6.8 Lens Copal 0 Shutter
Rodenstock APO Sironar N f 5.6 Lens 210 mm Normal Lens
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RODENSTOCK IMAGON 250MM H5.8 SOFT FOCUS LENS OUTFIT
Retina Rodenstock 85/4 Rotelar #4441435 … Minty
Rodenstock 300 MM F9 APO-Ronar Compur Shutter
Rodenstock Apo-Gerogon 270mm 1:9 Enlarging Lens
Rodenstock Rotelar 270mm f 5.6 Telephoto
Rodenstock Apo Ronar 9/300mm Compur Electronic 1
360mm MC Rodenstock Sironar-N 1:6.8 Cop 3 8×10 Lens
ANTIQUE GERMAN CAMERA PHOTO DOPPEL G.RODENSTOCK
Rodenstock for Leica screw mou 4,5/10,5cm Tele-Objektiv
