9.4.3 Configuration and calibration
When a Tachometer is supplied with an optional
4/20mA output the configuration menu is extended as
shown in Fig 18. The 4/20mA output sub-menu is
accessed via the
4-20 oP
function.
The 4/20mA output is controlled by the Tachometer
speed display, the speeds corresponding to 4 and
20mA output are defined in the sub-menu.
Fig 18 4/20mA output configuration sub-menu
9.4.4 Access 4/20mA output sub-menu:
4-20 oP
Access the Tachometer configuration menu as
described in section 6.2. Using the
&
and
*
push
buttons scroll though the menu until
4-20 oP
is
displayed, pressing
(
will then access the 4/20mA
output sub-menu which is shown in Fig 18.
9.4.5 Enable 4/20mA output:
EnbL
This function allows the 4-20mA output to be enabled
or disabled without altering any of the output
parameters. Using the
&
or
*
push button select
EnbL
in the
4-20 op
sub-menu and press
(
which will
reveal the existing setting
on
or
oFF
. The function can
be changed by pressing the
&
or
*
push button
followed by the
)
button to return to
EnbL
prompt in
the sub-menu.
9.4.6 Display which corresponds to 4mA
output:
4
.
000
The Tachometer speed display which corresponds to
a 4.000mA output current is defined by this function.
Using the
&
or
*
push button select
4
.
000
in the
4/20mA output sub-menu and press
(
to reveal the
existing speed display with one digit flashing. The
required display can be entered using the
&
or
*
push button to adjust the flashing digit and the
(
button to transfer control to the next digit. When set
as required, press
)
to enter the value and return
to the
4
.
000
prompt in the 4/20mA output sub-menu.
9.4.7 Display which corresponds to 20mA
output:
20
.
000
The Tachometer display which corresponds to a
20.000mA output current is defined by this function.
Using the
&
or
*
push button select
20
.
000
in the
4/20mA output sub-menu and press
(
to reveal the
existing speed display with one digit flashing. The
required display can be entered using the
&
or
*
push button to adjust the flashing digit and the
(
button to transfer control to the next digit. When set
as required, press
)
to enter the value and return
to the
20
.
000
prompt in the 4/20mA output sub-
menu.
Notes:
1. If the Tachometer calibration is changed
the 4/20mA output will automatically be set
to 3.5mA irrespective of the speed display.
The 4/20mA output should always be
reconfigured following changes to the
Tachometer configuration.
2. If the Tachometer and the 4/20mA current
sink output are powered from separate
supplies, the 4/20mA output current will
continue to flow when the Tachometer
supply fails or is turned off. Powering both
from a common supply eliminates this
effect.
38
Summary of Contents for BA314NG
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