TRIME
®
-PICO T3/IPH44 IPH50 Version 2_0
2017-05-30
Page 32
14
EMV/EMI Protection
EMV/EMI protection using ferrite filters ensures better interference suppression and therefore
improves measurement accuracy. Ferrite filters are integrated into the TRIME sensor and at the
connector end of the sensor cable.
15
Information on Lightning Protection of the
ENVIS Environmental Measurement System
(IMP-Bus,
GlobeLog Logger and integrated Sensors)
15.1
Introduction
Lightning strikes can cause considerable and costly damage to unprotected electronics. The
equipment is often totally destroyed. A good number of users are not or only partially insured.
Customers who have lightning protection insurance must comply with defined clauses regarding
lightning and excess voltage. Insurance companies only cover the damage when compliance
with the defined clauses has been proven. IMKO strongly recommends adequate lightning /
excess voltage protection equipment for ENVIS environmental measurement systems.
15.2
Excess voltage protection on 110/220V mains supply
Lightning strikes in proximity to high-voltage transmission lines can cause excess voltage in the
mains power supply which may result in damage of electronic components. Environmental
measurement systems with 110/220V mains supply are at risk from this excess voltage. It may
affect the whole system through the power supply unit and the central station (GlobeLog Log-
ger or SM-23U). Excess voltage can even enter the measuring system through the data acquisi-
tion computer’s mains power supply. An excess voltage protection is highly recommended for
all 110/220V devices connected to the ENVIS system.
15.3
Protection of modem and telephone lines
Telephone lines are at risk from excess voltage. If a modem is connected to the measurement
system the telephone line should also be protected by a lightning protection module.
15.4
Excess voltage protection for network modules by "SM-Blitz"
Excess voltage caused by lightning strokes in close proximity to the environmental measure-
ment test system may enter the IMP-Bus transmission lines. Longer lines increase the risk of
lightning strikes. Theoretically maximum protection is achieved by installation of a lightning pro-
tection module (SM-Blitz) in front of each SM-Module. Lightning protection is not cheap but it is
certainly worthwhile. A compromise should be found between costs and the maximum-
affordable protection, i.e. interconnection of adjacent SM-Modules to lightning protected
groups.
15.5
Lightning protection on meteorological towers
SM-Modules installed on meteorological towers cannot be protected from lightning strikes. The
field strength resulting from the electromagnetic fields and the associated accumulated energy
will cause damage to the electronics. Two solutions to the problem:
Erect a higher lightning conductor close to the meteorological tower serving as a light-
ning conductor.
Install the measuring modules a number of metres away. Then all lines coming from the
tower have to be protected by lightning protection modules.
