BEKA BA337E-SS, Руководство пользователя

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Using the
&
or
*
push button select
durAtion
in
the pulse output sub-menu and press
(
which will
reveal the existing pulse duration. The value can be
changed by pressing the
&
or
*
push button to
select the required value followed by the
)
button to
return to
durAtion
prompt in the sub-menu.
Note: This function only appears in the pulse output
sub-menu when the
5CALEd
is selected in the
5ource
sub-function (10.5.6).
10.5.9 Pulse storage
If the
diVidE
and
durAtion
functions are configured
such that the output pulse frequency with the specified
pulse width can not be output in real time, the number
of pulses will be stored and transmitted at the
maximum possible speed.
When the total display is reset to zero or the power
supply to the Rate Totaliser is disconnected or turned
off, any stored pulses will not be retained.
10.6 4/20mA output
The BA337E-SS Rate Totaliser can be supplied with
a factory fitted galvanically isolated 4/20mA output
which may be configured to represent the rate or
total display. Only one output option can be fitted to
a BA337E-SS.
10.6.1 Intrinsic safety
The 4/20mA output has been certified as a separate
galvanically isolated intrinsically safe circuit
complying with the requirements for
simple
apparatus. This allows terminals C1 and C3 to be
connected to any intrinsically safe circuit protected
by a certified Zener barrier or galvanic isolator
providing the output parameters do not exceed:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The maximum equivalent capacitance and
inductance of the 4/20mA output output is:
Ci = 2.2nF
Li = 4µH
To determine the maximum permissible cable
parameters, these figures should be subtracted from
the maximum cable capacitance and inductance
specified by the certificate for the Zener barrier or
galvanic isolator powering the 4/20mA output circuit.
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