5. CHANGING SETTINGS
IM 2493WVP-1
13
The POWER SERIES
Plus
has the option of analog output, which can provide an
analog signal relative to the input of the meter. The relationship between the
input and the output can be scaled by the user using the front panel. Analog
Output 1 is always proportional to the value shown on the top display (Watts).
Output 2 is always proportional to the middle display (VARs), and Output 3 will
always be proportional to the bottom display (Power Factor).
A 1phase/2wire/120Volt/5Amp wattmeter with 0 to 1 milliamp output, for
example, has the following default settings:
PT ratio: 1 to 1
CT ratio: 1 to 1
Analog Output LO: 0 Watts
Analog Output HI: 500 Watts
The LO is the input value at which the output
will be 0 mA. The HI is the input value at
which the output will be 1 mA. The charts at
right show the relationship of input and output.
When the settings are changed to:
PT ratio: 1 to 1
CT ratio: 1 to 1
LO: 50 Watts
HI: 450 Watts
The new relationship of input and output is
shown at right.
Next the PT ratio is changed to 2 to 1 (2:1).
Note that the HI and LO for input
automatically change to match the new ratio
whenever the PT ratio or CT ratio is changed.
The HI and LO for Power Factor are not
affected by PT and CT.
So now the settings are -
PT ratio: 2 to 1
CT ratio: 1 to 1
LO: 100 Watts
HI: 900 Watts
And the relationship is shown at right.
Special note for units with 0-1 mA/
±
1 mA
output:
0
100
200
300
400
500
0
0.25
0.5
0.75
1
DC Current Out (mA)
0
100
200
300
400
500
0
0.25
0.5
0.75
1
DC Current Out (mA)
0
200
400
600
800
1000
0
0.25
0.5
0.75
1
DC Current Out (mA)
