YSI IQ SensorNet 2020 XT Terminal - Manual (Page 40)

Installation System 2020 XT USB
3 - 10 ba76019e01 12/2012
3.4.4 Optimum installation of MIQ power supply modules
Basic rules  Install the MIQ power supply modules as near as possible to the
IQ S ENSOR N ET components with the highest power consumption.
This also applies in the case of several MIQ power supply modules
in the system.
 If possible, assemble the IQ S
ENSOR N ET in a star configuration from
the MIQ power supply modules.
3.4.5 Installation guidelines for lightning protection
When using the IQ S ENSOR N ET measuring technique, particularly in
outdoor areas, adequate protection against (electrical) surges must be
provided. A surge is a summation phenomenon of surge voltage and
surge current. It is generated through the indirect effect of a lightning
event or switching operation in the mains, in the grounding system and
in information technology lines.
To be adequately protected against the damaging effects of surges, an
integrated concept of the following protective measures is required:
 technical protective measures inside the instrument, and
 exterior protective measures of the installation environment.
With YSI online measuring technique, the technical protective
measures inside the instrument are already integrated as the so-called
lightning protection (see chapter 8 T
ECHNICAL DATA ).
The exterior protective measures of the installation environment can be
carried out observing the following guidelines:
1 All lines of IQ S ENSOR N ET systems must be
a) installed inside (or else close to) the grounded metallic mounting
constructions, e.g. handrails, pipes and posts if possible
b) or, particularly in the case of longer lines, laid in the ground.
Background: the small distance from the grounded metal
construction or the installation in the ground prevents the
development of induction loops between the cable and the ground
hazardous in the case of lightning strikes.