PN 305200901, Rev YT
Electromagnetic Compatibility (EMC)
Read and follow the recommendations in this section in order to avoid perfor-
mance variations or damage to the internal circuits of this equipment when
installed in harsh electrical environments.
The various congurations of the 3050-OLV Analyzer should not produce, or fall victim to, electromag-
netic disturbances as specied in the European Union’s EMC Directive. Strict compliance to the EMC
Directive requires certain installation techniques and wiring practices be used in order that erratic
behavior of the Analyzer, or its electronic neighbors be prevented or minimized. Below are examples
of the techniques and wiring practices to be followed:
In meeting the EMC requirements , the various Analyzer congurations described in this manual
rely heavily on the use of metallic shielded cables used to connect to the customer’s equipment
and power. Foil and braid shielded I/O and DC power cables are recommended for use in otherwise
unprotected situations. In addition, hard conduit, exible conduit, and armor around non-shielded
wiring also provides excellent control of radio frequency disturbances. However, use of these shield-
ing techniques is eective only when the shielding element is connected to the equipment chassis/
earth ground at both ends of the cable run. This may cause ground loop problems in some cases.
These should be treated on a case-by-case basis. Disconnecting one shield ground may not provide
sucient protection depending on the electronic environment. Connecting one shield ground via a
0.1 microfarad ceramic capacitor is a technique allowing high frequency shield bonding while avoid-
ing the AC ground, metal connection. In the case of shielded cables, the drain wire or braid connection
must be kept short. A two inch connection distance between the shield’s end, and the nearest ground-
ed chassis point, ground bar or terminal is highly recommended. An even greater degree of shield
performance can be achieved by using metallic glands for shielded cable entry into metal enclosures.
Expose enough of the braid/foil/drain where it passes through the gland such that the shield materials
can be wrapped backwards onto the cable jacket and captured inside the gland, tightened up against
the metal interior.
Inductive loads connected to the low voltage “Alarm Contacts” is not recommended. However, if this
becomes a necessity, proper techniques and wiring practices must be adhered to. Install an appropri-
ate transient voltage suppression device (low voltage MOV, “Transzorb”, or R/C) as close as possible to
the inductive device to reduce the generation of transients. Do not run this type of signal wiring along
with other I/O or DC in the same shielded cable. Inductive load wiring must be separated from other
circuits in conduit by the use of an additional cable shield on the oending cable.
In general, for optimum protection against high frequency transients and other disturbances, do not
allow installation of this Analyzer whereby its unshielded I/O and DC circuits are physically mixed with
AC mains, or any other circuit that could induce transients into the Analyzer or the overall system.
Examples of electrical events and devices known for the generation of harmful electromagnetic dis-
turbances include motors, capacitor bank switching, storm related transients, RF welding equipment,
static, and walkie-talkies.
x | 3050-OLV Moisture Analyzer
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