HIMA HIMatrix DI 24 01, Руководство пользователя

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4 Start-Up DI 24 01
Page 18 of 34 HI 800 201 E Rev. 1.00
4.1.2.1 Surges on Digital Inputs
Due to the short cycle time of the HIMatrix systems, a surge pulse as described in
EN 61000-4-5 can be read in to the digital inputs as a short-term high level.
The following measures ensure proper operation in environments where surges may occur:
1. Install shielded input wires
2. Activate noise blanking: a signal must be present for at least two cycles before it is
evaluated.
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Activating noise blanking increases the response time of the HIMatrix system!
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The measures specified above are not necessary if the plant design precludes surges from
occurring within the system.
In particular, the design must include protective measures with respect to overvoltage,
lightning, earth grounding and plant wiring in accordance with the relevant standards and
the instructions specified in the System Manual (HI 800 141 E or HI 800 191 E).