48
210
Reference Type
(REF. FUNCTION)
Value:
Sum (SUM)
[0]
Relative (RELATIVE)
[1]
★
External/preset (EXTERNAL/PRESET)
[2]
Function:
It is possible to define how the preset references are added to the other
references. For this purpose,
Sum
or
Relative
is used. It is also
possible, by using the
External/Preset
function, to select between the
external references and a preset reference.
Description of choice:
If
Sum
is selected, one of the preset references (parameters 211
through 214,
Preset Reference)
is added to the other external
references as a percentage of the reference range (minimum reference
through maximum reference).
If
Relative
is selected, one of the adjusted preset references (param-
eters 211 through 214,
Preset Reference
) is added as a percentage of
the total external reference.
If
External/Preset
is selected, it is possible to shift between the external
references and the preset references using terminals 16, 17, 29, 32 or
33 (parameters 300, 301, 305, 306 or 307,
Digital Inputs
). Preset
references are a percentage value of the reference range. External
reference is the sum of the analog references, pulse references and
any references from serial communication.
NOTE
If
Sum
or
Relative
is selected, one of preset
references is always active. If preset references
are not used, set value to 0%.
NOTE
See
Calculation of Resulting Reference
section
in this manual for mathematic formula to
calculate references.
Reference Type
The example below shows how the resulting reference is calculated
when Preset references are used together with Sum and Relative
references set in parameter 210,
Reference Type
. A formula for
calculating the resulting reference is given under Calculation of
Resulting Reference. See the drawing under Reference Handling.
Example:
The following parameters have been set:
Parameter 204
Minimum Reference:
10 Hz
Parameter 205
Maximum Reference:
60 Hz
Parameter 211
Preset Reference:
15%
Parameter 308
Terminal 53, Analog Input:
Reference
Parameter 309
Terminal 53, Min. Scaling:
0 V
Parameter 310
Terminal 53, Max. Scaling:
10 V
When parameter 210
Reference Type
is set to Sum, one of the
adjusted
Preset References
, parameters 211 through 214, will be
added to the external references as a percentage of the reference
range. If terminal 53 has an analog input voltage of 4 V, the resulting
reference will be:
Parameter 210
Reference type
=
Sum
Parameter 204
Minimum Reference
= 10.0 Hz
Reference contribution at 4 V
= 16.0 Hz
Parameter 211
Preset Reference
= 6.0 Hz
Resulting reference
= 32.0 Hz
If parameter 210
Reference Type
is set to
Relative
, one of the adjusted
Preset References
parameters 211 through 214 will be totaled as a
percentage of the sum of the present external references. If terminal 53
has an analog input voltage of 4 V, the resulting reference will be:
Parameter 210
Reference type
=
Relative
Parameter 204
Minimum Reference
= 10.0 Hz
Reference contribution at 4 V
= 16.0 Hz
Parameter 211
Preset Reference
= 2.4 Hz
Resulting reference
= 28.4 Hz
The graph in the next column shows the resulting reference while the
external reference changes from 0 to 10 V. Parameter 210,
Reference
Type
has been programmed for
Sum
and
Relative
. Parameter 211,
Preset Reference 1,
is programmed for 0%.
✭
I
ndicates factory default setting. Numbers in brackets [ ] represent selection as displayed on the serial bus.