Download Take a lot of care when connecting the circuit, to the place of the

ISW 8300
3 PHASE PROGRAMMABLE
DIGITAL WATTMETER
User Manual
INSTRUMENTS ET SYSTEMES
ZI des Radars, 12 rue Diderot
91350 GRIGNY
tel. : 33 (0)1 69 02 31 56
Fax. : 33 (0)1 69 02 08 93
ISW 8300
ISW83GB.DOC 08200
2
ISW 8300
Specifications ……………….........................................
4
Security ...............................................................….......
7
Warranty .................................................................…..
7
Changing a fuse .....................................……………....
7
Operation ......................................................………....
7
External current transformer .................………….…
14
Power measurements ………………………………….
16
Single phase measurements ..................................…...
19
Remote control ..........................................…………....
23
Analog Isolated Outputs (OPW2 option)………….....
32
3
ISW 8300
Specifications
Notes :
(18°C - 28 °C)
V = measured value
R = range
Voltage (true RMS)
Ranges :
15V 50V 150V 500 V
Resolution :
10mV 10mV 100mV 100mV
Accuracy (45-500 Hz) :
±(0.2% V + 0.2% R)
Input resistance :
4.8M 100pF
Manual or autoranging
Crest factor : max. 3 at full scale (1.5 at 500 V)
Overload : 1000 V peak
Current (true RMS)
Ranges :
0.5A 1.5A 5A 15 A (internal)
0.5A to 5000A with external transformer
(selectable ratio 1 to 1000)
Resolution :
0.1mA 1mA 1mA 10mA (internal)
0.1mA to 1A (external)
Accuracy (45-500 Hz) :
±(0.2% V + 0.2% R)
Crest Factor :
max. 3 at full scale (2 at 15 A)
Manual or autoranging
Overload :
30 A continuous, 60 A 1s
Active Power
Ranges :
7.5W to 7500W (16 ranges)
7.5W to 2500kW with external transformer
Accuracy (45-500Hz) :
±(0.3% V + 0.3% R) (U and I > 1/10
of range)
Resolution :
1mW to 1W according to range
1mW to 1kW with external transformer
Apparent Power
Ranges :
7.5VA to 7500VA (16 ranges)
7.5VA to 2500kVA with external
transformer
Accuracy (45-500Hz) :
determined by U and I accuracy (see
formulas)
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ISW 8300
Resolution :
Reactive Power
Ranges :
1mVA to 1VA according to range
1mVA to 1kVA with external transformer
7.5VAr to 7500VAr (16 ranges)
7.5VAr to 2500kVAr with external
transformer
Accuracy (45-500Hz) :
determined by U and I accuracy (see
formulas)
Resolution :
10mVAr to 1VAr according to range
10mVAr to 1kVAr with external transformer
Power Factor
Display :
-1.000 to +1.000 (plus sign indicates
inductive power, minus sign indicates
capacitive power)
Accuracy (45-500Hz) :
determined by U and I accuracy (see
formulas)
Safety :
CEI 1010-1 Cat III 600 V
Interface
RS232 (3 wires). Xon-Xoff. protocol
Transmission rate 1200/9600 Baud
All functions and ranges programmable
Power :
230 V ±10 % , 50-60 Hz, max. 10 VA
Temperature
of utilisation
Dimensions
Weight
Misc. :
Options
10-40 °C RH < 80 %
240 x 240 x 88mm (L x l x H)
about 1,5kg
Simultaneous display of 4 parameters
(10mm LED display).
Beeper indicates overload.
OPW2 3 wide bandwidth isolated outputs (U, I
or P according to display).
The primary quantities U (voltage) and I (current) are sampled and calculated.
Voltage, current and active power have their own tolerance. The calculating
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ISW 8300
formulas of the next page are necessary to calculate the tolerances of the
secondary quantities as a function of the tolerances of the primary quantities.
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ISW 8300
Formulas
Freq = frequency of the signal
N = number of samples (N >120)
Remark: The formulas which give apparent power, reactive power and capacitors
are applicable only for sinusoidal voltages and currents.
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ISW 8300
Safety
INSTRUMENTS et SYSTEMES certifies that this instrument has left the factory
in perfect working order, both in operation and safety.
This instrument has been designed and manufactured with great care to bring the
user the best possible safety to the user. If the instrument no longer functions
properly or is damaged, it must be immediately disconnected from the ac supply
voltage, from the measured circuit voltages and returned for repair.
Opening, maintenance, repair and calibration must be carried out by qualified and
approved personnel.
Warranty
Provided it is used under the recommended conditions, this instrument is
guaranteed for a two year period against manufacturing defects and component
failure. This warranty applies to material and workmanship. The instrument must
be shipped back to an agreed repair center. It will be repaired or replaced without
charge. Warranty repairs are made at the discretion of IES.
Maintenance
Your wattmeter does not need any specific maintenance. Whenever cleaning is
necessary, use a soft material. Avoid water or liquids that may penetrate inside.
Operation
Carefully unpack the instrument and make sure that it was not damaged during
transportation. Insert the power cord on the rear of the instrument and connect to
the ac supply. Switch power on by means of the power switch located on the rear
panel.
8
ISW 8300
9
ISW 8300
10
ISW 8300
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ISW 8300
Symbols used
Indicates the possibility
of a dangerous voltage
Refer to the user manual
Changing a fuse
Before you change a fuse, disconnect the instrument from all possible
dangerous voltages!
The defective fuse must be replaced using a fuse of the same type and value.
Selectable Options
At start up, the instrument displays first the software version, the transmission rate
of 1200 or 9600 Baud and finally selects the V function (Voltage measurement).
Buzzer
The buzzer indicates overrange conditions or manipulation errors. It can be
switched ON or OFF (toggle) in the following way:
Switch OFF the instrument. Hold the V key in and switch ON. Release
the V key when The V function is reached. The new state of the buzzer is
kept in memory until you decide to change it.
RS 232 Transmission Rate (1200/9600 Baud)
Proceed in the same way as for the buzzer but press the A key before start up.
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ISW 8300
Input Terminals
The Input Terminals are located on the rear panel of the instrument. Each channel
has separate terminals for voltage and current inputs. Voltage measuring circuits
are isolated from current measuring circuits and isolated from channel to channel.
Therefore, it is possible to measure the current in a “cold” or “hot” point.
The voltage and current terminals are marked “+” and “-“. This is to indicate the
phase relationship between them. Connect the circuit so that a positive voltage on
the “+” voltage terminal generates a positive current flowing through the “+”
current terminal. Under these conditions the power dissipated into a resistance
will be positive.
Bad wiring may lead to important errors in three phase systems !
NEUTRAL Terminal
All voltage circuits are differential. The instrument generates a virtual neutral
which is the average voltage of the three phases. This potential appears on the
neutral terminal. When the neutral of the three phase system exists, it must be
connected to the NEUTRAL terminal. The reference of all measurements is then
exactly defined.
Measurement of the same quantity on three phases
The display of the same quantity on three phases permits the comparison of these
quantities (unbalanced system) and indicates the average value (or the sum) of the
quantities. For example, when power (W) is selected, the display indicates the
power of each phase and the total power.
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ISW 8300
The different quantities which may be displayed are:
- voltage (V)
- current (A)
- active power (W)
- reactive power (VAr)
- apparent power (VA)
- power factor(PF)
- power factor compensation capacitors (µF)
The fourth displayed quantity () represents the sum (W, VAr, VA) .
One Phase measurements
One phase measurements indicates - for the selected phase or for the total systemvoltage (V), current (A), active power (W) and reactive power (VAr).
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ISW 8300
Voltage and current ranges
There are four voltage ranges and four current ranges. At power-up, autoranging
is set (AUTO is lit). To change from AUTO to manual ranging, push the
corresponding lever up or down. The first pressure switches AUTO off, further
pressures switch the ranges up or down.
The voltage and current ranges are switched simultaneously on the three phases.
In AUTO mode, the ranged is switched up if at least one display is higher than
1600 counts (15V - 150V – 1.5A) or 5500 counts (50V – 0.5A - 5A).
The range is switched down if at least one display is lower than 1300 counts
(500V - 50V - 5A) or 450 counts (150V- 1.5A- 15A).
Overrange is indicated by a bip and the display blinks (" - OL - "display .
A current or voltage overrange may lead to the impossibility to calculate a
quantity (e.g. power) . This is indicated as " - - - - - ". The reason of overrange
must be cancelled. Select VOLT or AMP function to see which quantity
overranges.
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ISW 8300
Current measurements with an external transformer
Measuring currents with an external transformer is specially useful:
- to increase the current capacity to 5000 Amps transformer ratio 1000:1
- to perform current measurements by means of a current probe. It is not necessary
to open the circuit to insert the current measurement
Any current range is available for external measurements. The selected range
must however be compatible with the output current of the transformer. For
example, for a transformer with a nominal 5A output, select the 5A range. For a
transformer delivering 1A, select the 1.5A range.
Connect the outputs of the current
transformer to the current inputs of the
wattmeter
Take care when you connect the transformer, to respect the phase relationship
between current and voltage across the load. You can perform a quick check by
connecting a resistive load. The measured power should be positive. I the power
is negative, invert the current inputs.
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ISW 8300
To use an external current transformer
.
Place the CURRENT PROBE switch on
the rear panel in the EXT position.
Select the appropriate current
range
Select the set n function.
With the + and – keys, adjust
the transformer ratio to the
desired value.
Enter the value OK.
Note: the set n function can be set
Only in the current probe switch is in the
EXT position.
The current ratio is the ratio of the primary current to the secondary
current. It is an integer which may be comprised between 1 and 1000. The
same current ratio is applied to the three phases.
The use of an external transformer is pointed out on the front panel by the
EXT indicator.
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ISW 8300
Power measurements
With separate circuits to measure current and voltage, a lot of configurations are
possible to determine the power absorbed by a load, or the power supplied by
each phase.
Take a lot of care when connecting the circuit, to the place of the current
measurements. In three phase systems the currents issued by each phase are
summed and generate components which are not in phase with the input voltages.
Improper wiring may lead to wrong results like measurement of reactive power in
a purely resistive circuit.
This is always true when external current probes are used. The probes prevent
from opening the circuit but must be place in the right way.
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ISW 8300
PH1
I1
Z1
Z2
Z3
I2
I3
PH2
PH3
U1
U2
U3
N
STAR CONFIGURATION
PH2
PH1
U1
Z1
I1
I2
Z3
Z2
U3
I3
U2
PH3
TRIANGLE CONFIGURATION
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ISW 8300
THREE WATTMETER METHOD
When the load is not balanced, the total power will be measured by means of the
three wattmeter method. If the neutral connection is not available, the artificial
neutral ( N black plug) may be used.
The total power is displayed as :
P = P1 + P2 + P3
TWO WATTMETER METHOD
In 3 wires networks (without neutral), the two wattmeter may be used. The total
power is displayed as :
P= P1 + P2
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ISW 8300
Single phase measurements
The synchronization signals needed for the measurement are always supplied by
phase 1 (PH1). Therefore :
In single phase measurements, always use phase 1 (PH1).
Single phase measures do not put particular problem. On the other hand, the fact
of using a three phase wattmeter with separate circuits allows unusual
measurements as :
 Measurement of three powers and total power
 Comparison of powers
 Difference of powers
To measure the power applied to three different loads, connect the voltage inputs
in parallel and each ammeter to a load (see drawing). The three powers and the
sum appear on the four displays (W, VAr or VA function). Of course it is also
possible to display the currents.
To measure a difference of powers, it is just necessary to invert an ammeter in
series with one of the two loads. The displayed power becomes negative and the
fourth displays indicates the difference.
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ISW 8300
PH
PH1
I1
I2
I3
PH2
U1
U2
U3
Z1
Z2
Z3
PH3
S
N
Measurement of the sum of powers
PH
PH1
I1
I2
PH2
U1
U2
Z1
Z2
S
N
Measurement of the difference of powers
22
PH3
ISW 8300
X1000 indicator
All power measurements are displayed in W (active power), VA (apparent
power) or VAr (reactive power).
When the measured value does not fit in the display, the X1000 indicator lights.
The displayed values must then be multiplied by 1000, which is equivalent to a
display in kW, kVA or kVAr.
Power factor
The power factor is defined as the ratio :
PF =
Active Power / Apparent Power
The power factor is always positive and smaller than 1.
The only knowledge of the value of the power factor does not inform about the
phase shift between voltage and current (lead or lag), that is the inductive or
capacitive character of the power. That is why, a sign is added to the power factor.
By agreement:
When the power factor is negative, the power is capacitive. When it is positive,
the power is inductive.
Compensation capacitors
The compensation capacitors are used when the power absorbed by an installation
has an important inductive component (transformers, engines …).
The calculation of their value lies on the knowledge of the reactive power with
pure sine waves. Currents are rarely perfectly sinusoidal because of the usually
poor linearity of inductive materials. The optimal value of the capacitors may be
slightly different of the displayed values.
A negative capacitor, while wiring is correct indicates that the reactive power is
already capacitive.
To measure voltages and currents
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ISW 8300
The ISW8300 Wattmeter measures alternating voltages and currents with a
frequency comprised between 20Hz and 10000 Hz in three phase or single phase
systems.
Single phase measurement must always be conducted on the phase 1 (PH1).
The internal synchronization signals are always supplied by the phase 1. If
another channel is used or if the voltage or current is too small, the readings will
be unstable.
The voltage measurement is differential. The red ( + ) and black ( - ) plugs may be
inverted without any danger. The “polarity” of the input terminals is useful only to
keep the right phase between voltage and current in power measurements.
The voltage input of the three channels are isolated from one another.
Current inputs are also symmetrical, isolated from one another and isolated from
voltage circuits. Therefore, the current may be measured anywhere in the circuit.
Caution : the current inputs have a very small resistance of only a few milliohms,
nearly a short circuit. Take care when connecting the circuit that the protective
elements (fuses, circuit-breakers) are in a correct state of safety.
The voltage and current inputs may be overloaded without damage, even on the
most sensitive ranges.
At start up, the instrument selects autoranging for voltage and current. When no
power is connected to the inputs, the most sensitive ranges are connected. The
choice of a particular range is useful to examine (for example with the analogue
isolated outputs), the start-up current of a motor. The whole start sequence is not
disturbed by the range switching.
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ISW 8300
Remote control
To select the transmission rate
You have the choice between two transmission rates between the instrument and
the computer, 1200 or 9600 Baud. The Baud rate is displayed during a short time
at start up. To modify it, switch the instrument off, press the A key for a few
seconds and switch power on. The new selected rate is displayed and kept in
memory until a new change is done.
Connection
The dialogue between the computer and the wattmeter is accomplished by means
of a software protocol (Xon-Xoff). The connection needs only a simple 3 wires
cable (Rxd, Txd and signal ground).
The connecting cable can be terminated at one end with a 9 pin connector and at
the other end with a 9 pin or 25 pin connector, this depends on the PC serial port
connector. The following connections should be followed:
25 pin
female connector (PC)
9 pin female
connector (PC)
9 pin male connector
(instrument)
2
3
7
3 (Tx)
2 (Rx)
5 (GND)
3
2
5
RS 232 cable
To check the communications
You can quickly and easily check the connection with the "TERMINAL" option
of Windows™.
First, switch the instrument off and on to check the transmission rate. If you want
to change it see section "To select the transmission rate".
Enter the Terminal mode under Windows™ (or execute the program
Terminal.exe). Select the following configuration in terminal:
25
ISW 8300




TTY terminal emulation
terminal parameters: LF => CR/LF for Input and Output
communication parameters: transmission rate 1200 or 9600 Baud.
8 Bits, no parity, 1 Stop Bit, Xon-Xoff
Send the command *IDN?. The instrument sends back the string:
IeS ISW8300 Vxx , where Vxx is the hardware version number.
Commands
The commands are sent as a string of ascii letters and digits. No special symbol or
space should be added. Once sent, the command is executed upon reception of the
carriage return character (CR = Hex 13). In terminal mode, this character is
transmitted by the ENTER key of the keyboard, along with the Line Feed
character which is ignored.
Note: the commands may be written either in UPPER or
lower case.
Some commands will force the instrument to answer. It is the case for the
commands:





*IDN? : identification
VERSION? : software version
STATUS? : configuration of the instrument (see § STATUS string)
DATA? : all measurements are sent
VAL? : measured value. If the command arrives during the measurement
cycle, the result will be sent only at the end of the cycle.
 VAS? status and measured value query
 MA1 : continuous output mode. Each result is sent to the computer. This mode
is cleared by the MA0 command.
 N? : external current transformer ratio.
The table of the last page lists all the available commands.
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ISW 8300
STATUS string
Set N function
If the set N function (external current transformer setting) is active when a status
string is requested, the status chain has the value :
"SETN".
For the other functions, the status chain sent back after reception of the
STATUS? command has the following structure:
WATT
AU1
|
|
function
voltage
VOLT
AU: auto
AMP
MU: manual
WATT
1: 15V
VAR
2: 50V
VA
3: 150V
KW
4: 500V
KVar
KVA
PF
CAP
PH1 (KPH1) *
PH2 (KPH2) *
PH3 (KPH3) *
SIG (KSIG) *
AI2
|
current
AI: auto
MI: manual
1: 0.5A
2: 1.5A
3: 5A
4: 15A
x100
|
ext. Mode
xNNNN: ext. current transformer
ratio NNNN
* K indicates that the active and reactive powers are expressed in KW and KVAr.
The different fields are separated with one or more spaces.
Measurement Result
The measurement result is transmitted :


after a VAL? (value) or VAS? (value and status) query
after a DATA? query (all results)
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ISW 8300

after each measurement if the device is in the auto transmit mode (MA1
command). In this case it is preceded by the status string of the
instrument.
If the set N function is active, the result is sent as a single value. In the other
cases, the output string is built using the four displayed values. Each quantity is
preceded by a heading representing the function. The values are formatted as the
display. The different fields are separated with spaces. If an overflow occurs (the
displays indicates "- - - - "), the value is replaced by the "OF" string.
V1 =123.4
|
V1
I1
P1
Q1
S1
PF1
C1
V1
V2
V3
V
V2 =125.3
|
V2
I2
P2
Q2
S2
PF2
C2
I1
I2
I3
I
V3 =126.0
|
V3
I3
P3
Q3
S3
PF3
C3
P1
P2
P3
P
V =124.9
|
V
voltage measurement
I
current measurement
P
active power
Q
reactive power
S
apparent power
PF
power factor
correction capacitors
Q1 phase 1
Q2 phase 2
Q3 phase 3
Q
sigma
The response to a DATA? query comprises all the measurement values for the
three phases. The output string comprises 7 lines:
voltage (1) voltage (2) voltage (3)
current (1) current (2) current (3)
power (1) power (2) power (3)
react. pow. (1) react. pow. (2) react. pow. (3)
app. pow. (1) app. pow. (2) app. pow. (3)
pow. factor (1) pow. factor (2) pow. factor (3)
capa (1) capa (2) capa (3)
The values have a precision of 3 digits after decimal point.
The response to a VAS? query is a string made of the status followed by the
measurement result.
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ISW 8300
The measurement result is transmitted only at the end of the measurement cycle.
Therefore, if a result is requested during the cycle, the result will be transmitted
after a variable delay (max 400 ms).
Automatic Measurements
Once the MA1 command has been sent, the measurement data is automatically
transmitted after each measurement. The output string includes the instrument
status and the value. In this way, the user is continuously informed of the
configuration of the instrument.
The automatic mode is reset by sending a MA0 command or switching off and on
the instrument.
Selction of voltage or current ranges
When the instrument is powered up, the autoranging mode is selected for voltage
and current. Then the ranges may be selected in two different ways:

With a MAN_U command for voltage or MAN_I command for current. The
AUTORANGE mode is reset and the range previously selected remains.

Select directly a range with a SET:Ux command for or SET:Ix for current (x
indicates the range form 1 to 4). Autoranging is canceled..
Set N Command
The SET:N=xxxx command sets the ratio of the external current transformer.
The ratio is an integer comprised between 1 and 1000. It must be transmitted with
4 digits (e.g. SET:N=0010).
To disable the front panel
The front panel may be disabled in remote operation by means of the command
FAV0. The instruments now only responds to the commands from the interface.
This mode is cancelled with the command FAV1 or when the instrument is
switched off and on again.
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ISW 8300
FUNCTION
RANGE
MODE
MISC.
30
VOLT
AMP
WATT
VAR
VA
PF
CAP
PH1
PH2
PH3
SIGMA
SET:U1
SET:U2
SET:U3
SET:U4
SET:I1
SET:I2
SET:I3
SET:I4
AUTO_U
MAN_U
AUTO_I
MAN_I
SET:N=xxxx
DATA?
VAL?
VAS?
STATUS?
N?
FAV1
FAV0
MA1
MA0
*IDN?
VERSION?
BEEP
BEEP0
BEEP1
Voltage measurement
Current measurement
Active power measurement
Reactive power measurement
Apparent power measurement
Power factor measurement
Correction capacitors
Phase 1 measurements
Phase 2 measurements
Phase 3 measurements
Sum measurements
15V range
50V range
150V range
500V range
0.5A range
1.5A range
5A range
15A range
Autoranging (voltage)
Manual selection (voltage)
Autoranging (current)
Manual selection (current)
Ext. transf. ratio =xxxx
Send all results
Send displayed values
Send displayed values and status
Send status
Send ext. transformer ratio
Lock front panel
Unlock front panel
Auto transmit mode
Cancel MA1 mode
Send identification
Send version
Beep
Beeper OFF
Beeper ON
ISW 8300
TO USE THE PC_WATT SOFTWARE
Installation and de-installation
Start Windows®. Insert the PC_W3P floppy disc and execute the file :
or
a:setup to install the software
a:desinst to de-install it
The directory ISW8300 will be created during installation. It includes the icon
used to start the software. If you want to keep the ability to de-install the software,
you must maintain the same structure.
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ISW 8300
To use the PC_WATT software
Operating modes
Two different operating modes are allowed, the "Terminal" mode and the
"Command" mode. In Terminal mode, the computer only monitors the front
panel of the wattmeter, which is driven with its own keys. In the Command mode,
the front panel is disabled and the instrument is operated with the mouse or the
keyboard of the computer. The software starts in Terminal mode. You can
modify this mode in the Configuration menu.
Starting
Connect the interface cable and double click onto the PC_W3P icon to start the
software. If the software finds the wattmeter, it directly enters the monitor mode.
Else, it opens a communication window where you can modify the transmission
speed or the PC serial port to use.
Display
The Display menu selects the different windows that appear on the screen:


The function/range window which reproduces the front panel of the
wattmeter
The communication windows which displays the dialogue between the
instrument and the computer
Help
The help file is opened with the F1 key of the keyboard (dedicated help) or by the
? menu (global help).
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ISW 8300
Measurements
The measurements may be accomplished and stored in a file at a desired rate.
The Options menu opens a window where you can define the maximum number
of measurements, the time interval between measurements and the structure of the
object file. The measurement cycle is initiated with the Start button.
The cycle starts as soon as you have typed the name and path of the result file.
The result file is a text file with different columns. Each column represents a file
selected in the proposed list (function, value, unit, time, date). Note that the value
is always selected.
The measurement cycle is halted or started at any time with the Start
Measurement and Stop Measurement options of the Measure menu.
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ISW 8300
OPW2 Option
Analog Isolated Outputs
The OPW2 Option is an optional card which enables monitoring of voltage,
current or power on an oscilloscope.
The card uses high insulation voltage optocouplers to separate the output from
the measurements circuits. It is also isolated from the interface output.
Outputs
The option outputs three signals on three different BNC connectors (numbered 1,
2 and 3).
The signals which appear on the outputs depend on the displayed values :

If the display shows three phase voltages (or currents, or active powers), the
interface delivers the corresponding signals.

If the display shows the voltage, current and power of a single phase, the
interface delivers the same information. The reactive power is not output.
The outputs are active only when voltage, current or active power are displayed.
Amplitude
The voltages output to the oscilloscope are bipolar and referenced to zero.
A full scale voltage (e.g. 15V on the 15V range) generates a 1Vrms output.
For power, the full scale range is obtained by multiplying the voltage range by the
current range.
Specifications
Output amplitude :
Accuracy :
Offset voltage :
Bandwidth (typ.):
Output resistance :
Max. applied voltage :
Common mode voltage :
34
1V full range
voltage, current : ± 2% power : ±5 %
voltage, current : ± 30mV power : ± 50mV
voltage, current : 40kHz power : 20kHz
10 kOhms
±30V
±30V