BEKA BA364E, Руководство пользователя

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4.2.5 Open collector input
Most certified open collector sensors located in the
same hazardous area as the BA364G Counter may
be directly connected to pulse input terminals 5 & 6
or 9 & 10 providing the sensor and associated wiring
can withstand a 500V rms insulation test to earth.
The open collector device must comply with the
requirements for
simple apparatus or have input
safety parameters equal to or greater than:
Ui > 10.5V dc
Ii > 9.2mA dc
Pi > 24mW
See section 6.6 for details of the typical maximum
counting frequency.
4.2.6 Magnetic pick-off input
CoiL
in the input configuration menu is a low level
voltage pulse input intended for use with magnetic
pick-off sensors producing an ac output. For a
CoiL
input the pulse input terminals 5 & 6 or 9 & 10 of the
BA364G Counter comply with the requirements of
simple apparatus allowing connection to any certified
intrinsically safe magnetic pick-off within the same
hazardous area as the Counter having output
parameters equal to or less than:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The maximum permitted cable parameters will be
defined by the magnetic pick-off’s intrinsic safety
certificate less the Counters input parameters Ci & Li
which are small and can often be ignored.
See section 6.6 for details of the typical maximum
counting frequency.
4.2.7 Voltage pulse input
Two voltage pulse input ranges are selectable in the
configuration menu,
VoLt5 L
and
VoLt5 H
. When
configured for either of the voltage pulse ranges, the
pulse input terminals 5 & 6 or 9 & 10 of the BA364G
Counter comply with the requirements of
simple
apparatus. This allows direct connection to any
intrinsically safe voltage source within the same
hazardous area as the Counter having output
parameters equal to or less than:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The maximum permitted cable parameters will be
defined by the voltage source intrinsic safety
certificate
less the BA364G Counter input
parameters which are small and can usually be
ignored.
See section 6.6 for details of the typical maximum
counting frequency.
4.2.8 Remote reset
The BA364G Counter’s total display may be
remotely reset by connecting terminals RS1 & RS2
together for more than one second. Permanent
interconnection
inhibits totalisation. Remote
resetting may be accomplished by any mechanically
operated switch located in the same hazardous area
as the Counter providing it and the associated wiring
can withstand a 500V rms insulation test to earth.
No galvanic isolator is required.
A BA364G Counter may also be remotely reset to
zero from the safe area.
Any switch may be used
but a galvanic isolator or IS relay is required to
transfer the contact closure into the hazardous area.
Almost any device with a contact that may be
connected to equipment in the hazardous area may
be used for this application. Fig 4 illustrates how a
BA364G Counter may be reset from both the safe
and the hazardous area.
Note: The BA364G can also be configured to reset
the total display when the
&
and
*
push buttons
are operated simultaneously for more than three
seconds - see 6.24.
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