VEGA VEGAPULS 81 - Manual (Page 49)

VEGAPULS 64 and 81 49
Electrical connection
5 Electrical connection
5.1 Connection and connection
cable
Safety information
Ensure that the instrument is unpressurized
before you start work. Always switch off the
power supply before you carry out clamping
work on the radar sensors. Protect yourself
and the instruments.
Skilled staff
Instruments which are not operated with a
protective low voltage must only be connected
by skilled staff.
Connection
A standard two-wire cable can be used as
connection for the output signal. Very often the
“electromagnetic pollution“ by electronic ac-
tuators, energy transmission and transmitting
stations is so considerable that the two-wire
cable for the output signals (digital or ana-
logue) should be screened.
We recommend to use a screening. This
screening prevents against future interfer-
ences. Earth the screen of the signal line al-
ways at one sensor side and use a low imped-
ance earth connection (foundation, plate or
mains earth).
Ex-protection
If an instrument is used in hazardous areas,
the appropriate regulations, conformity certifi-
cates and type approvals for systems in Ex-
areas must be noted (e.g. DIN 0165).
Intrinsically safe circuits with more than one
active facility (instrument delivering electrical
energy) must not be connected. Note the
special installation regulations (DIN 0165).
Connection cable
Note that the connection cable must be speci-
fied for the expected operating temperatures
in your systems.
Cables with intrinsically safe circuits must be
marked (blue) and must not be used for other
circuits.