Infratek SM201, Руководство пользователя

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Menu i(t): The wave form display of current can be selected with the control key M5 . In the
frequency range 5Hz to 1600Hz the graph shows one cycle and above 1600Hz eight
cycles. The time base is given by the frequency indication in the display number field.
The top of the vertical axis is given in mA or A and is automatically scaled.
Menu
u(t): Finally, the wave form display of voltage can be selected by pressing the control
key M6 . In the frequency range 5Hz to 1600Hz one cycle is displayed 1600Hz eight
cycles. The time base is given by the frequency indication in the display number field,
e.g. the frequency indication shows 100.0Hz then one cycle corresponds to 10ms. The
vertical axis is automatically scaled and the top of the scale is given in mV or V.
5.10. SHORT TIME INTEGRATOR
The following quantities can be integrated for the duration of the selected measurement time: real-
, apparent-, and reactive power, and rectified mean current. The resulting values are energy in Wh,
apparent energy in VAh, reactive energy in Varh, and charge in Ah. The sign of the quantity to be
integrated is taken into account, that is, the displayed energy can be negative.
This is how you activate the short time integrator for a specific quantity, let’s say, for active
power. Move the cursor to active power display field and press
SET .
The third menu along the bottom edge of the display shows
σ
dt indicating that active power is
one of the quantities that can be integrated. When you press now M3 the
σ
annunciator appears
next to the
DC/AC-annunciator or, if it was selected before
σ
, it disappears. The
σ
annunciator indicates that
power is integrated for the duration of the selected measurement time.
For long time energy computation refer to the section
ENERGY COMPUTATION .
5.11. ENERGY COMPUTATION AT 50HZ
The SM201 allows long time energy computation of real-, apparent- and reactive power and
charge computation using rectified mean current. In the
HOLD mode the display values are held
and the energy computation is stopped. Range changes during the measurement are allowed and
do not influence the result, accumulation over a period of more than 10 years is possible. The
resolution goes from
nWh to MWh . Scaling of current and voltage are correctly taken into
account.
5.11.1. SET-UP FOR ENERGY MEASUREMENT
Let us assume all the energies need to be determined. Move the cursor to the number field where
you want to place active energy. Press
SET ; the selection table is presented. Move the cursor now
to ENERGY and press the SET-key again. By this time you are back in the number field. The
menu at the bottom of the display shows „ HOLD, ACT, APP, REA, RESET, ,“ and gives you
the choice of active-, apparent-, and reactive power. To place active power in this number field
press
M2 , the annunciator ACT in the annunciator field indicates the type of energy.
Similarly you proceed to place apparent energy in another number field, that is, move the cursor to
this field, press the
SET-key and select ENERGY , press SET again to come back to the number
field, and finally press M3 to select apparent energy.
In a similar manner reactive energy is set-up. Note that the accumulated values are indicated by
ACC.
5.11.2. SET-UP FOR CHARGE MEASUREMENT
Charge is determined by integrating the rectified mean value of current. So far we have set up 3
energy values. Let’s put the value of charge to a fourth number field as follows: move the cursor
to this number field. Press the
SET-key move the cursor to RECT of current, press the SET-key
again to have the rectified mean current displayed in this number field. The menu at the bottom
shows
„HOLD, ,
σ
dt, RESET, , ,“. Pressing M3 once you select short time integration, press
M3 again to select the desired longtime charge accumulation. The annunciator shows A , meaning
charge accumulation and the units in the number field are Ah .
5.11.3. RESETTING, STARTING, AND STOPPING
This is how you reset the energy values. Move the cursor to a number field displaying energy.
Press
RESET (M5) . Before starting a measurement energy and charge values are normally reset
to zero. All three energy values can be reset together, charge reset is separate. With the reset of the
energies are also reset the
FLICKER values.
This is how you can proceed. Bring the Spectral Multimeter to HOLD and reset energy- and
charge values. Press HOLD to start the measurement and press HOLD again to stop it.
5.12. SCALING OF CURRENT- AND VOLTAGE INPUTS
When the Spectral Multimeter starts up it’s current- and voltage scaling factors are set to 1.0.
When you are using any kind of transducer or current transformer you can scale the inputs to have
actual current-, voltage-, and power values displayed.
To change the scaling factors enter the
SETUP menu. Move the cursor to the scaling factor you
want to change. Let’s assume you want to change the current scaling factor to 250. Press SET . At
this point you can modify single digits with the up- and down arrows. Move the cursor to the first
digit and set it to 2, move the cursor one digit to the right and set it to 5, and finally modify the
exponent to 02 and press SET to store the selected factor. The new scaling factor looks like this:
Scale I +2.499999e02
which is very close to 250 for all practical purposes.