BEKA BA364G, Manual

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Providing the BA367NE Counter is correctly installed
in an Ex n panel enclosure located in Zone 2, the
input terminals may be connected to a certified
sensor located in Zone 1 as shown in Fig 5. The
sensor should have Ex e or Ex d certification
permitting installation in Zone 1. Intrinsically safe
Ex i certified sensors should not be used.
Fig 5 Connection to an Ex d or Ex e sensor in Zone 1
4.2.1 Input switching thresholds
For reliable operation the Counter pulse input must
fall below the lower threshold and rise above the
upper thresholds shown in the following table.
Input transducer
Switching thresholds
Lower Upper
Open collector 2k

10k

Voltage pulse low 1.0V 3.0V
Voltage pulse high 3.0V 10.0V
Magnetic pick-off 0mV 40mV peak
Proximity detector 1.2mA 2.1mA
Switch
100

1000

Sensors with a switch contact, proximity detector or
an open collector output require energising which is
achieved by linking Counter terminals 3 and 4.
4.2.2 Switch contact input
Any mechanically or magnetically activated switch
contact speed sensor located in Zone 2 or in the
safe area may be directly connected to the pulse
input terminals 5 and 6 which are non incendive,
providing the sensor and associated wiring can
withstand a 500V rms insulation test to earth. Most
magnetically activated reed relays comply with these
requirements.
The BA367NE contains a
configurable debounce circuit to prevent contact
bounce being counted. See section 6.6.
4.2.3 Open collector input
Open collector sensors located in Zone 2 or in the
safe area may be directly connected to input
terminals 5 & 6 providing the sensor and associated
wiring can withstand a 500V rms insulation test to
earth.
The BA367NE contain a configurable debounce
circuit to prevent false triggering. See section 6.6.
4.2.4 2-wire proximity detector input
Most Zone 2 certified NAMUR 2-wire proximity
detectors may be directly connected to a BA367NE
input terminals 5 & 6, providing the minimum
operating voltage of the proximity detector is greater
than 7.5V. The sensor and the associated wiring
should be able to withstand a 500V rms insulation
test to earth.
The BA367NE contain a configurable debounce
circuit to prevent false triggering. See section 6.6.
4.2.5 Magnetic pick-off input
Magnetic pick-off sensors usually have a low level
ac voltage output which a BA367NE Counter can
sense when configured for a
CoiL
input. The
Counter input terminals 5 and 6 may be connected
to any Zone 2 certified magnetic pick-off output
sensor, providing the output in normal operation is
equal to or less than 30V the Counter's Ui. The
sensor and associated wiring should be able to
withstand a 500V rms insulation test to earth.
The BA367NE contain a configurable debounce
circuit to prevent false triggering. See section 6.6.
4.2.6 Voltage pulse input
Two voltage pulse input ranges are selectable in the
BA367NE Counter configuration menu,
VoLt5 L
and
VoLt5 H
. The Counter input terminals 5 and 6 may
be connected to any Zone 2 voltage pulse output
sensor, providing the output in normal operation is
equal to or less than 30V the Counter's Ui. The
sensor and associated wiring should be able to
withstand a 500V rms insulation test to earth.
The BA367NE contain a configurable debounce
circuit to prevent false triggering. See section 6.6.
4.3 Remote reset
The BA367NE Counter's total display may be
remotely reset to zero by connecting terminals RS1
and RS2 together. Permanent interconnection
inhibits the Counter. Remote resetting may be
accomplished by any mechanically operated switch
located in Zone 2 as the Counter's reset circuit is
non incendive. The reset switch and the associated
wiring should be able to withstand a 500V rms
insulation test to earth.
A BA367NE may also be remotely reset from the
safe area. Any switch may be used. Fig 4 illustrates
how a BA367NE may be reset from both the safe
and the hazardous area.
The BA367NE total display may also be reset when
the
&
and
*
push buttons are operated
simultaneously in the operating mode i.e. when the
instrument is counting. See 6.19
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