PRESCO PVM-100 User manual
Presco AG
Zürcherstrasse 70 -CH 8104 Weiningen Tel. + 41 44 750 63 63 Fax + 41 44 750 63 66
Internet : www.prescoag.com
Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 1 of 6
Peak Voltmeter
Type PVM-100
Instruction Manual
Table of contents
1 Safety precautions
1.1 Safety
1.2 Safety precautions
1.3 Impaired Safety Precautions
2. Introduction
2.1 Function Principle
3. Technical Data
3.1 Scope of supply
4. Measuring arrangements
5. Measurements
6. Servicing
Presco AG
Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 2 of 6
1 Safety precautions
1.1 Safety
The instrument described in this manual is designed to be used by properly trained per-
sonnel only. Adjustment, maintenance and repair of the exposed equipment should be
carried out only by qualified personnel aware of the hazards involved.
1.2 Safety precautions
For correct and safe use of this instrument it is essential that both operation and service
personnel follow generally accepted safety procedures in addition to the safety precau-
tions specified in the manual. Specific warning and caution statements, where they apply,
will be found throughout the manual. Safety is the responsibility of the user.
Warning!
The Instrument is an electronic system foreseen and de-
signed for low voltage operation. The whole equipment works
in high voltage environment and therefore all instructions and
precautions which apply for such operations have to be con-
sidered working with the measuring instrument.
1.3 Impaired safety precautions
Whenever it is likely that safety protection has been impaired, the instrument must be
made inoperative and be secured against any unintended operation. Safety protection is
likely to be impaired if, for example, the instrument fails to perform the intended meas-
urements or shows visible damage.
Presco AG
Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 3 of 6
2. Introduction
2.1 Function Principle
The measuring instrument is a peak detecting digital voltmeter with differential input.
Fig. 1 shows the principle of the measurement
Fig.. 1
The input unit is a differential amplifier with 1 Minput impedance. It is proposed to
ground the input "UinL" and apply the voltage on the UinH input.
The peak detector is an ultra –linear active peak detecting circuit.
The digital voltmeter has 3.5 digits.
The instrument has only one scale factor; in the given case, 100 V input results in a 100
kV display.
The instrument makes one decade autoranging: at 10 kV it increases the resolution.
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Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 4 of 6
3. Technical Data
Peak Voltmeter Type PVM 100
To be connected to a standard capacitor with built-in capacitive divider
Displayed value Upeak /2
Display scale factor 100 kV / 100 V
Highest input voltage to ground at any terminal 200 V peak
Display LED 3 ½ digit
Resolution 0.1 kV / 10 V
Uncertainty 1 % 1 digit
Input impedance 1 M
Dimensions W 255 x H 110 x D300 mm
Weight 2.6 kg
Power Mains 115 / 230 V / 50 / 60 Hz
With front and rear panel connectors
Reference conditions
temperature 23° C ± 2° C
humidity 45 ... 75%
altitude (pressure) 101.3 kPa
Rated range of use
according IEC 359
temperature 5° C ... 40° C
humidity, non condensing 20 ... 95%
altitude (pressure) 70 ... 106 kPa
3.1 Scope of supply
1 p. peak voltmeter type PVM-100
1 p. power chord
1 p. test certificate
1 p. instruction manual
Presco AG
Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 5 of 6
4 Measuring arrangements
4.1 The front of the instrument (Fig. 2)
Fig.2.
Establish a ground connection between ground of the laboratory and the ground terminal
of the instrument.
Because the instrument is built according to safety class I of IEC 359, the mains cable
contains a ground conductor which also has to be connected to ground of the local mains.
It is strictly forbidden to open the ground connection between "labo-
ratory ground " and "Instrument ground of local mains"!
Danger of life!
4.2 Using the instrument with a divider.
HV to be measured
CH
CL
1M
KV-M100
BNC
Front
Back
H L
Surge Arrester 230V
Surge Arrester 90V
The instrument can be used with resistive, capacitive, inductive divider or voltage trans-
former.
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Manual_PVM100-Englisch.DOC/ PO/19.07.07 Page 6 of 6
The example above shows a connection with a capacitive divider.
The low voltage part of the divider must be dimensioned in a way that the 1 Mload imped-
ance of the instrument causes lower than 1 % error.
Example:
The high voltage capacitor (CH) is: 100 pF
For a 100 V output at 100 kV input we need a low voltage capacitor of: CL= 99 900 pF
The error, resulted by the 1 Mload is: =( (1/2)*(*R*C*L)2)-1= 0.2%
5.2 Measurement
Make the test set up using the example above.
Connect input green-yellow (GROUND) to laboratory ground
Connect input black (UinL) to ground point of divider
Connect input blue (UinH) to the dividing pint of divider
Switch on the instrument
Now you can begin the voltage measurement
Warning:
Although the instrument is safe, there is no protection against certain application errors
and carelessness. In case of unsteadiness please consult a senior specialist instead of
damaging the test object or the instrument.
Caution:
Do not forget that using the instrument you work in a high voltage environment. Thought-
less handling and switching can be lethal.
6 Servicing
Repair work and maintenance can only be done by qualified personnel of Presco AG. In
case of problems please contact the representative which delivered the instrument or
Presco AG directly.
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