HEIDENHAIN TNC 306 Technical Manual - Manual (Page 21)

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TNC 416/TNC 406/TNC 306 Installation 3/99
2 Installatio n
2.1 Electrical noise immunity
Please note that the vulnerability of electronic equipment to noise increases with faster signal
processing rates and higher sensitivity. Please protect your equipment by observing the following
rules and recommendations.
Noise voltages are mainly produced and transmitted by capacitive and inductive coupling. Electrical
noise can be picked up by the inputs and outputs to the equipment, and by the cabling.
Possible sources of interference are:
– Strong magnetic fields from transformers and electric motors
– Relays, contactors and solenoid valves
– High-frequency equipment, pulse equipment and stray magnetic fields from switch-mode
power supplies
– Mains leads and leads to the above equipment
Electrical interference can be avoided by:
– A minimum distance between the logic unit (and its leads) and interfering equipment > 20 cm.
– A minimum distance between the logic unit (and its leads) and cables carrying interference
signals > 10 cm.
(Where signal cables and cables which carry interference signals are laid together in metallic
ducting, adequate decoupling can be achieved by using a grounded separation shield)
– Screening according to DIN VDE 0160.
– Potential compensating lines ø 6 mm² (see grounding plan).
– Use of original HEIDENHAIN cables, connectors and couplings.