502 069 02
Manual
Power Monitor, PD 3260
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SWNo $AB: FullScale.
FullScale is a record having the following structure:
Record
Current: Real;
(* FullScale for current inputs *)
(* Offset = 0 *)
VoltageU: Real;
(* FullScale for Voltage.U input *)
(* Offset = 4 *)
VoltageV: Real;
(* FullScale for Voltage.V input *) (* Offset = 8 *)
VoltageW: Real;
(* FullScale for Voltage.W input*)
(* Offset = 12 *)
End;
FullScale.Current is a common fullscale for the current inputs. The current inputs are calibrated
to be identical, so the chosen current mesurement transformers must be of the same type and ratio.
FullScale.VoltageU, FullScale.VoltageV and FullScale.VoltageW, are separate fullscale values
for the voltage inputs. The FullScale values can be written directly to the variables or they can be
calculated automatically. Automatic calculation is disabled when the channel is in input
simulation mode.
Example: A 10:1 ratio current transformer is selected to match the current to be measured, with
the nominal 1A RMS input current of the module.
The 10A RMS primary current needed to give 1A RMS at the input of the module, can be written
directly into FullScale.Current. The value of FullScale.Current can also be calculated automati-
cally, by writing the readout of a reference amperemeter, connected in series with the primary of
the transformer in L1, into the Current.U variable. The calibration current used for automatic
calculation of fullscale, should be larger than 20% of fullscale.
Example: A 230:24 ratio voltage transformer is selected to match the voltage to be measured,
with the nominal 24V RMS input voltage of the module.
The 230V RMS primary voltage needed to give 24V RMS at the input of the module, can be
written directly to the FullScale.VoltageU/V/W variables. The fullscale values for the voltage
inputs can also be calculated automatically, by writing the readout of a reference voltmeter
connected to the primary side of the measurement transformer, to the corresponding
Voltage.U/V/W variables. The calibration voltage should be a reasonable fraction of fullscale.
SWNo $AC: Factors.
The factors variable is a record having the following structure:
Record
PowerScale: Real;
(* Offset = 0 *)
EnergyScale: Real;
(* Offset = 4 *)
End;
The Factors variables, PowerScale and EnergyScale, are unit conversion factors for the readout
of power and energy.
