BASI BBI250 Operation Manual page 2

Overview
Mounting
Electro-Magnetic Interference (EMI) Issues
Important note:
A built-in RC noise
suppression circuit may
be connected in parallel
with relay contacts.
Full AC voltage isolation
may NOT be provided
when relay contacts
are open.
Small AC current
(≈ 1.5 mA at 230 VAC)
may still flow through
the RC circuit!
BBI250 is a programmable process indicator
with an input for various linear current, voltage,
or resistive signals, a fully programmable tri-color
LED bargraph that allows setting the color
of each dot, 'dot' or 'bar' display mode as well
as customized scale, and a bright 3-digit LED
display. The device may be also equipped with
up to 2 programmable relays providing ON/OFF
control / alarm with or without pulse mode.
♦
Place BBI250 into a 42x90 mm panel cut-out.
♦
Tighten it into place using the enclosed
mounting brackets.
♦
All signal wires must be shielded.
They must not be packaged together
with power cables!
♦
Never lay the signal wires close
to inductive or capacitive noise sources,
such as relays, contactors, motors, etc.!
♦
All shields have to be grounded ONLY
at one end, as closer as possible
to the indicator terminals!
♦
Avoid sharing supply lines with powerful
consumers, especially with inductive loads,
switched on and off.
♦
To stop unwelcome interference signals
entering through the power supply lines,
use shielded 1:1 isolation transformer!
♦
Shunt all switched (not only those switched
by the indicator) inductive consumers
with special suppression networks:
RC group and varistor - for AC loads,
or diode - for DC loads.
♦
If the indicator operates in a very powerful
EMI area, it has to be mounted inside
a grounded metal shielding box!
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