BEKA Advisor A90-SS, Руководство пользователя

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The position of the displayed decimal point does
not affect the position of the decimal point in any of
the other configuration menus. Therefore when
adjusting the
CAL
,
5et
or
bar
functions, the
decimal point position within the function should
normally be set to the same as that selected in this
dp
function.
5.7 Calibration of the digital display using an
external source:
CAL
This function, which is only included in the
configuration menu when the meter has been
configured for a current or voltage input, enables
the zero and span of the A90-SS panel meter to be
adjusted using an external calibrated voltage or
current source. When used with an accurate
traceable source, such as a calibrator, this is the
preferred method of calibration.
Input range Zero Span
4-20mA 4mA 20mA
0-50mA 0mA 50mA
0.1V 0V 0.1V
1V 0V 1v
10V 0V 10V
To calibrate the meter select
CAL
from the
configuration menu and press ( . The meter will
display
2Ero
which is a request for the zero input
current or voltage. Adjust the external calibrator to
the zero input current or voltage and again press
( which will reveal the current zero A90-SS
meter display with one digit flashing. The flashing
digit of the meter display can be changed by
pressing the
&
or
*
button. When set as
required pressing ( will transfer control to the
next digit. When all the digits have been adjusted,
pressing
( will transfer control to the decimal
point which should normally be positioned in the
same place defined in the
dp
function. Finally
press ) to enter the new meter zero display and
return to the
2Ero
prompt.
Pressing the
*
button will cause the meter to
display
5PAn
which is a request for the span input
current or voltage. Adjust the external calibrator to
span input and again press
(
which will reveal
the existing span meter display with one digit
flashing. The flashing digit can be changed by
pressing the
&
or
*
button. When set as
required pressing ( will transfer control to the
next digit. When all the digits have been adjusted,
pressing
( will transfer control to the decimal
point which should normally be positioned in the
same place defined in the
dp
function. When set
as required press ) t o enter the new span and
return to the
5PAn
prompt. Finally press
)
again
to return to the configuration menu.
Notes:
a. The A90-SS meter input current or voltage must
be adjusted to the required value before the
2ero
and
5pan
functions are entered by
pressing the
(
button.
b. Meters may be calibrated at current and voltage
inputs other than the values shown above,
providing the difference between the two is
greater than 25% of the meter input range. If
these conditions are not complied with, the
meter will display
FaiL
and the calibration will
be terminated.If the zero input is greater than
the span input the meter will be reverse acting
i.e. an increasing input will cause the display to
decrease.
5.8 Calibration of the digital display using
an internal reference:
5Et
This function, which is only included in the
configuration menu when the meter is configured
for a current or voltage input, enables the meter to
be calibrated without the need for an accurate
external current source and without the meter input
terminals being disconnected.
The meter’s internal reference is used to simulate
calibration inputs, therefore the actual meter input
does not have to be known during calibration.
Although not traceable or as accurate as the
CAL
function, this method of calibration is acceptable
for many industrial applications. The Zero and
Span calibration inputs are shown below.
Input range Zero Span
4-20mA 4mA 20mA
0-50mA 0mA 50mA
0.1V 0V 0.1V
1V 0V 1v
10V 0V 10V
To calibrate the A90-SS panel meter display select
5Et
from the configuration menu and press (.
The meter will display
2Ero
, pressing ( again will
reveal the current display at zero input with one
digit flashing. The flashing digit can be adjusted
by pressing the
&
or
*
button. When set as
required pressing
(
will transfer control to the
next digit. When all the digits have been adjusted,
pressing
(
will transfer control to the decimal
point which should normally be positioned in the
same place defined in the
dp
function. Finally
press ) to enter the new meter zero display and
return to the
2Ero
prompt.
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