MV DAC-30
Test and diagnosis system for medium voltage cables
MV DAC-30
Test and diagnosis system for medium
voltage cables
The MV DAC-30 is a DAC (Damped AC Voltage) test set
with a peak voltage of 30 kV. The test set can be used for
quality control on newly installed cables, in accordance with
the IEEE 400.4 standard. In addition, to prevent unplanned
outages, the unit can also be used for condition-monitoring
purposes on aged cable circuits.
The main use of the DAC test set is to identify, evaluate and
locate partial discharge (PD) faults in the insulation and acces-
sories of all types of medium voltage power cables. PD activi-
ty is an indication of incipient insulation faults and is therefore
widely regarded as one of the best ‘early warning’ indicators
of deteriorating medium and high voltage insulation.
Partial discharges are regarded as the main breakdown
cause for MV and HV cables. Performing ofine PD meas-
urements on MV and HV cables using a DAC voltage test
set helps support the asset management process so that the
correct decisions are made for future maintenance and re-
placement activities.
Since the DAC frequency of the test voltage is close to nom-
inal AC service conditions, all measured PD activities can be
accurately evaluated and compared with the power frequen-
cy. The PD inception voltage (PDIV) and PD extinction volt-
age (PDEV) can be easily determined due to the decaying
amplitude of the test voltage.
■
Safe operation thanks to enclosed
metallic casing, integrated voltage source
and PD detector
■
Uses well proven DAC excitation voltage
for PD measurements (acc. IEC 60270)
■
Live evaluation and display of results
■
Two part design for easy transportation
DESCRIPTION
The system consists of two parts: the control unit (including
laptop), and the HV unit. The HV unit divides in two, mak-
ing transport and set-up much easier. One of the unique
features of the MV DAC-30 is that the HV unit consists of a
voltage source with an internal PD detector. Unlike with oth-
er PD measurement systems, the cable under test is the only
accessible live component when testing with the MV DAC-
30, making it much safer.
The operating software guides the user through the entire
process. Some key features are:
■
Integrated cable database
■
Fully automatic calibration
■
Live PD mapping: evaluation and display of results
during the actual measurement
■
Reporting by mouse click
2
Seba Dynatronic
Mess- und Ortungstechnik GmbH
Dr.-Herbert-Iann-Str. 6
96148 Baunach
Germany
T 0049 9544 68-0
E team.international@megger.de
SALES OFFICES
Megger GmbH
Obere Zeil 2
D-61440 Oberursel
Germany
T 0049 6171 92987-0
E info@megger.de
MVDAC30_DS_EN_V01
www.megger.com
ISO 9001
The word ‘Megger’ is a registered trademark.
* We reserve the right to make technical changes.
ORDERING INFORMATION
Product Order no.
MV DAC-30 1006132-S
MV DAC-30 control and HV unit, laptop, calibrator, SW license, set of cables (incl. 5 m HV-connection cable)
Options:
HV-connection cable 5 m 2006817
HV-connection cable 10 m 2008839
HV-connection cable 15 m 2008840
Rugged ight case for control unit 90017826
Rugged ight case for HV unit 90017827
MV DAC-30
Output voltage
DAC
Precision
Resolution
3 … 30 kV
peak
± 1 %
0.1 kV
Frequency range 20 ... 500 Hz
Capacity range 1 nF ... 10 μF at 20 kV
peak
1 nF ... 4,25 μF at 30 kV
peak
PD sensitivity range 2 pc … 100 nC (acc. to IEC60270)
Resolution ± 1 pC
System noise level < 20 pC at 30 kV
peak
PD impulse repetition rate 100 kHz
PD localisation
Measuring range
Propagation velocity
Sampling rate
Bandwidth
Precision
Resolution
0 … 16,000 m / V/2 = 80 m/µs
5 … 120 m/µs
125 MHz (8 ns)
3/25 MHz (switchable)
1 % of the cable length
± 1 pC / ± 0.1 m
Filter Analog and digital
Input voltage 110/230 V, 50/60 Hz, 500 VA
Temperature
Operation
Storage
- 20 °C … 55 °C
- 30 °C … 70 °C
Relative humidity 93 % at 30 °C (non-condensing)
IP rating IP 20
Weight
HV module
Control module
30 kg
25 kg
Dimensions (W x D x H) 56 x 42 x 100 cm
TECHNICAL DATA* FEATURES
■
Safe-to-touch, enclosed metallic casing
■
Internal PD Detector
■
“Live” evaluation and display of results
■
Two part design for easy transportation
■
Conforms to VDE safety standards
■
High test capacity