BEKA BA344D, Руководство пользователя

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To assist with system design, the Zener barrier
system certificate specifies the maximum cable
parameters for popular barriers and lists some
of the diode return barriers that may be
used.Fig 3 illustrates the basic circuit that is
used when a BA344D is connected to a pulse
source in the safe area and / or is reset in the
safe area. For simplicity, connections for the
optional alarms are included in the accessory
section of this manual – see section 9.
Fig 3 BA344D used with Zener barriers
When designing a system it is important to
remember that terminals 4, 6 and 8 are
interconnected within the BA344D - see Fig 1.
4.3 Use with Galvanic Isolators
Galvanic isolators are probably the simplest
intrinsically safe interface as they provide
isolation and do not require a high integrity
earth connection.
Any certified galvanic isolator with output
parameters less than the input parameters of
the BA344D may be used. To assist with
system design, the galvanic isolator system
certificate specifies some popular devices and
defines the maximum cable parameters.
Fig 4 BA344D used with galvanic isolators
Fig 4 illustrates the basic circuit that is used
when a BA344D is connected to a pulse
source in the safe area and / or is reset in the
safe area. For simplicity, connections for the
optional alarms are shown in accessory section
of this manual – see section 9.