BVM PQSensor MkVI Guide

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 1 -

PQSensor™ MkVI
Installation & Commissioning
Manual
(also PQSensor MkIII)
BVM Systems Limited
21 Springvale Road
Gilford
Craigavon
BT63 6EB
United Kingdom
Email: [email protected]
www.bvmsystems.co.uk
Patents: 1295133, 6,919,717
BVM Systems Limited
BVM Systems

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 2 -
Important Safety Notice
Aspects of the installation and commissioning of the PQSensor™ involve working on equip-
ment where errors in installation or failure to follow appropriate safety procedures could result
in exposure of personnel to Lethal High Voltages.
Installation of the PQSensor™ should only be performed by personnel with the necessary
knowledge and training.
Pay particular attention to the safety aspects of those sections of the manual marked with the
symbol.
Ensure that the CVT input is solidly earthed at all times when any installation work is being car-
ried out.
Never open the CVT secondary terminal box unless the CVT is solidly earthed.
Always ensure the bottom end of C2and the EMU are solidly earthed before energising the
CVT.
The nominal output signal from the PQSensor™ is 63.5V. This can be present at any time that
the PQSensor™ is energised.

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 3 -
1 GENERAL
The purpose of a PQSensor™ is to equip a standard CVT with an interface that enables it to
be used to make accurate measurements of harmonic levels and transients on h.v. power net-
works.
The PQSensor™ consists of three separate components
The Measurement Unit (MU)
The Signal Conditioning Module (SCM)
The Interconnecting Cable
An example of a PQSensor™ installation is shown in Figure 1.
When installing the SCM box it is essential to ensure that it is positioned below the safety clear-
ance height that will permit it to be accessed while the CVT is in service. The ideal mounting
height for the PQSensor™ SCM is between 0.9m and 1.5m above ground level and for future
access and serviceability after commissioning it should always be mounted in this area.
1.1 The Measurement Unit
The Measurement Unit (MU) is a 66mm (w) x 66mm (d) x 81mm (h) module that contains the
transducers that acquire the signals used to produce its high accuracy wide band voltage out-
put. There are two sets of inputs, HCCT and LCCT together with their associated outputs. The
PQSensor™
CVT Electromagnetic Unit
Tank
CVT Secondary
Terminal Box
PQSensor™ Signal
Conditioning Module (SCM)
PQSensor™Mounting Plate
PQSensor™
Interconnecting
Cable
CVT Support
Structure
PQSensor™ - Installation
PQSensor™
Supply and
Output Signal Wiring
Figure 1

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 4 -
Measurement Unit is also equipped with a test circuit that can be used for on-site testing and
calibration. Detailed dimensions of the Measurement Unit are given in Appendix I. It is equipped
with three M3 mounting holes on the base. These holes are compatible with the Phoenix UTA98
DIN rail adapter (provided) and can also be used together with other custom made mounting
plates.
1.2 The Interconnecting Cable
The Interconnecting Cable, with a standard length of 3 metres, takes the signals from the Meas-
urement Unit to the SCM. Lengths up to 5m are available on request. Both ends of this cable
are provided pre-terminated and equipped with the appropriate glands for making off in the CVT
secondary Terminal Box and the SCM Box. This steel wire armour (SWA) cable contains two
individually screened twisted pairs together with a collective screen. The twisted pair conduc-
tors in this cable are stranded with 0.5mm2nominal conductor area - usually a 16/0.2 conductor
stranding.
1.3 The SCM
The SCM is designed to be mounted on the structure of the CVT as shown in Figure 1. Dimen-
sions and mounting details for the box are provided in Appendix II. The OEM must provide a
mounting plate or bracket on the CVT structure compatible with the holes shown in the drawing
in Appendix II. The mounting plate is not supplied with the PQSensor™ as there many different
types of CVT support structures.
2 INSTALLATION OF THE MEASUREMENT UNIT IN THE CVT TERMINAL BOX
Whether the PQSensor is being installed in a new CVT at the time of factory test or being ret-
rotted to a CVT that is already in service the rst step is to install the MU in the secondary ter-
minal box of the CVT. The function of the MU is to measure the currents owing in the capacitor
divider circuit and in the primary winding of the CVT wound transformer (the electromagnetic
unit or EMU). These circuits are normally available in the CVT secondary terminal box and are
usually connected directly to ground with links. The installation of the MU involves the replace-
ment of these links with the input circuits of the MU - the MU HCCT input circuit replaces the
capacitor divider earth link and the MU LCCT input circuit replaces the EMU primary ground link
C1
C2
PQSensor
Measurement
Unit
LCCT 1
LCCT 2
HCCT 1
HCCT 2
To Signal
Conditioning Unit
(SCM)
a
n
N / P2
HF
EMU
Figure 2

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 5 -
(see Figure 2). The polarity of these inputs must be respected by connecting the HCCT2 and
LCCT2 inputs to ground as shown. Use a schematic of the target CVT to identify the connec-
tion points for these MU inputs. In all cases a marked up CVT schematic must be used for the
design, installation and checking of the MU installation.
In many cases the bottom of the capacitor circuit is called the ‘HF’ terminal as this is where
power line equipment can be connected. The bottom of the EMU circuit is sometimes referred
to as P2 or N.
The MU is tted with a Phoenix UTA 89 TS35 DIN rail adapter and in many cases this can be
used to mount the MU on an available section of DIN rail in the CVT terminal box. The DIN rail
adapter can be removed and the three mounting holes can be used with a third party custom
bracket if required.
After the Measurement Unit has been installed the terminations of the HCCT and LCCT inputs
must be carefully checked to ensure that they have been correctly and securely made and are
physically robust, as an incorrect or faulty connection will result in LETHAL VOLTAGES being
present in the CVT secondary terminal box when the CVT is energised. If in any doubt about
the installation or connection points for the MU inputs consult a qualied technical expert in your
organisation.
The HCCT and LCCT input circuits are low impedance circuits with guaranteed continuity that
will not have any impact on the earth circuits of the Capacitor or EMU circuits of the CVT. These
circuits are formed using a single piece of cable with no connections or joints.
For the safe operation of the CVT it is essential that the integrity of capacitor and EMU earth
paths are preserved. To ensure this is the case we recommend carrying out the following test
after the MU has been installed in the CVT secondary terminal box.
• Using a secondary injection test set (e.g. Sverker) inject 1A ac between the bottom of the
capacitor stack (HF) and ground.
• Measure the voltage drop from the bottom of the capacitor stack and ground (Figure 3)
• The measured voltage should be less than 40mV ac (equivalent to 40mΩ)
• Repeat the about test between the bottom of the EMU and ground where the measured volt-
age should be less than 60 mV.
C1
C2
PQSensor
Measurement
Unit
LCCT 1
LCCT 2
HCCT 1
HCCT 2
a
n
N / P2
HF
Sverker
V
EMU
Figure 3

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 6 -
3 FACTORY INSTALLATION AND CALIBRATION OF THE PQSENSOR™
Only the Measurement Unit is permanently installed in the CVT in the factory - the Intercon-
necting Cable and the SCM should be installed as part of the site installation and commission-
ing procedure. However, for test purposes, the SCM must be connected to the CVT, usually us-
ing a dedicated cable installed in the factory test bay to permit the PQSensor™ to be calibrated
when rated voltage is applied to the CVT.
3.1 Measurement Unit Installation
See Section 2 for details of the Measurement Unit (MU) installation.
3.2 Factory Calibration Of The PQSensor™
To perform the calibration of the PQSensor™ SCM it must be wired to the Measurement Unit
installed in the CVT terminal box as shown in the wiring diagram in Appendix IV.
This can be done using the Interconnecting cable provided with the PQSensor™ or for factory
testing a dedicated Interconnection Cable between the CVT test bay and the SCM under test/
calibration can be used. This cable must be twin twisted pair cable with individual and collective
screens connected as shown in the wiring diagram in Appendix IV.
A suitable supply voltage must be connected to the PQSensor™ SCM on terminals 4 & 5 - this
can be 110V - 230V ac or 110V dc - this supply input is not polarity sensitive. Terminal 3 must
be grounded.
This calibration process involves adjusting the output of the PQSensor™ so that it delivers its
Nominal Output Voltage when the CVT is energised with nominal substation voltage.
With the CVT energised with nominal substation voltage measure the SCM output voltage on
terminals 4 & 5 with a calibrated true rms voltmeter. Using the output adjust potentionmeter set
the output voltage to be equal to the PQSensor Nominal Output Voltage as given in the PQSen-
sor Test report.
N.B. Record the results on the calibration label inside the PQSensor. Also record the serial
number of the CVT on the same label to ensure that at site the PQSensor™ is installed on the
CVT with which it has been calibrated.
4 SITE INSTALLATION AND TESTING OF THE PQSENSOR™
4.1 Mounting The SCM Enclosure.
The signal conditioning module (SCM) box is a weatherproof IP65 enclosure, with approxi-
mate dimensions of 260mm x 160mm x 90mm. For full details of dimensions and mounting
hole locations see Appendix II. The SCM box is typically installed on the CVT support structure
in a vertical position with the cable entries on the bottom face. There must be a solid ground
connection between the SCM enclosure and the CVT structure, This is usually achieved by
making a ground connection to the CVT structure using the earth tag provided as part of the
interconnection cable gland kit.

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 7 -
N.B. A mounting plate or bracket will be required
to secure the SCM to the CVT structure. Since
there is a wide variety of support structures used
in substations this bracket is NOT provided with the
PQSensor™ and will normally be sourced locally.
4.2 Installation in Hot Climates
In climates where ambient temperatures can ex-
ceed 40˚C it is highly recommended to mount the
SCM in a location that will afford the maximum
shade from direct sunlight. While the PQSensor™
is rated for temperatures up to 65˚C in warmer cli-
mates it is prudent to limit exposure to direct sun-
light. This is best achieved by using a mounting
plate at least 500mm wide which is fitted on the
shaded side of the CVT structure. A sun shade can
also be provided for such installations.
4.3 Installing the Interconnecting Cable
The Interconnecting cable is 3m in length and is
pre-terminated at both ends for connection between
the CVT secondary terminal box and the SCM en-
closure. The interconnecting cable should be wired
between the MU in the CVT secondary terminal
box and the SCM using the SWA cable glands sup-
plied. First terminate the connections in the SCM
as shown in Figure 3 and the drawing in Appendix
IV and then terminate the other end of the cable
on the MU in the CVT terminal box. A full wiring
diagram for the Interconnecting Cable in contained
in Appendix IV. The interconnecting cable should be securely xed to the CVT structure at as
many points as necessary to ensure there are no loose sections of cable.
4.4 Supply Voltage and Output Signal connection
In addition to the connections to the Measurement Unit the supply voltage and the output signal
need to be connected. These connections should be made using stranded cable with a mini-
mum size of 1mm2.
The PQSensor™ accepts a universal supply and can be powered from 110V ac, 230V ac or
80 - 250V dc. A ground/earth connection must always be made to pin 3 of the PQSensor™ user
connection terminal block.
The nominal output signal from the PQSensor™ is of the order of 60V ac so appropriate safety
precautions should be taken when working with a voltage of this level. For safety purposes it
should be assumed that when the PQSensor™ is powered on there is always a voltage of 60V
ac present on the output terminals.
The PQSensor™ is intended to be used with recording equipment that has an input impedance
of greater than 1Mohm.
Supply Voltage:- 110/230V ac, 88 - 250Vdc
Part No. 18-0049-
PQSensor™
Serial No.
16. Earth
15. Screen (White)
14. LCCT (Black)
13. LCCT (Blue)
12. Screen (White)
11. HCCT (Black)
10. HCCT (Blue)
9. Earth
8. Aux (Cmn)
7. Aux
6. Earth
5. O/P (Cmn)
4. O/P
3. Earth
2. Neutral / -
1. Live / +
CVT Serial Number
Factory Test Voltage
FieldTest Voltage
Date Sign
Date Sign
Output (V)
Output (V)
O/P Adj.
HCCT
LCCT
EARTH
Figure 3

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 8 -
4.5 PQSensor™ Installation wiring check
When the CVT is energised it is not possible to gain access to the CVT secondary terminal box
so the wiring must be checked and tested before energisation. To facilitate testing apply a suit-
able supply voltage to the SCM. Next, using a secondary injection test set inject the Reference
Test Current as given in the PQSensor™ test report between the ‘Test’ terminal (5) on the MU
and ground and measure the PQSensor output voltage. The output voltage should be within
2% of the Nominal Output Voltage as given in the SCM Test Report. If the measured voltage is
outside tolerance then the installation wiring should be checked as this is the most likely cause
of the output voltage error.
4.6 Site Calibration Of a PQSensor™ retro-fitted to an existing installed CVT
Using a calibrated voltmeter measure the output voltage of the SCM while the CVT is energised.
The output voltage should be equal to the Nominal Output Voltage as given by the PQSensor™
Test Report. If required use the output adjust potentionmeter to correct for any difference.
Where the substation primary voltage differs from nominal voltage the expected PQSensor™
output voltage can be scaled accordingly.
When testing is complete record the substation voltage and output voltage on the results label
provided inside the PQSensor™.
4.7 Site Verication For a Factory Calibrated PQSensor™
For a factory calibrated PQSensor™ no site calibration is required as this will have been com-
pleted by the CVT manufacturer. However the output voltage value should be checked after the
CVT has been energised.
Where the substation primary voltage differs from nominal voltage the expected PQSensor™
output voltage can be scaled accordingly.

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 9 -
Appendix I

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 10 -
Appendix II
SCM Dimensions
16. Earth
PQSensor™
BVM Systems Limited
BVM Systems
Patent Nos:- 1,295,133 and 6,919,717
Mounting Holes
110 mm centres
Overall width 160 mm
Mounting Holes 240 mm centres
Overall height 260 mm
depth 92 mm
Mounting Hardware - M6 x 35mm hex bolts - 4 o
M6 Washer - 4 o
M6 Nut - 4 o

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 11 -
Appendix III
PQSensor™- Sample Test Reports
Date:- ________________
Customer:- _____________
Serial Number:- 1909-2555
P.O. Number
Input Continuity Check
Test Current (A) 2.64
Resistance (mOhm) 30.02
Result Pass
Hi-Pot Test (2.5 kV ac)
I/P - O/P (mA) 0.10
I/P - Gnd (mA) 0.12
O/P - Gnd (mA) 0.26
Result Pass
MU Ratio And Phasing Check
HCCT Ratio Test Error
0.95%
LCCT Ratio Test Error
0.71%
HCCT & LCCT Phasing
Pass
Overall Result Pass
Signed
Measurement Unit Test Report

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 12 -

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 13 -

www.bvmsystems.co.uk
[email protected]
40-0287-12 - 14 -
Appendix IV
PQSensor Wiring Diagram
Test
HCCT
LCCT
HCCT
LCCT
HCCT1
HCCT2
LCCT1
LCCT2
Measurement
Unit
Test
Black Blue Black Blue
1
2 3 4 5 6
10 11 12 13 14 15 16
3 4
5
1
2
PQSensor SCM
TB1
Black Blue
White
Black Blue
White
Black
Supply 1 Supply 2
110/230Vac 100-250Vdc
(not polarity
sensitive)
Earth
Output Output Common
Cable armour grounded by cable gland
Cable armour grounded by cable gland
Armour
Collective Screen
Indivdual Screen
Earth
Note
SCM terminal 3 must always be connected to ground
MU terminal 6 must always be grounded MU terminal 5 should be unconnected when the PQSensor is in service
No other connections are required on TB1
Date
App:-
Rev:- Details:-
Ckd:-
Sign
Additional details added
JM MW
30.09.19 30.09.19
06
BVM Drawing No.:- Sheet :- of
Title:-
BVM Systems Limited
BVM Systems
Size
17-0151 1 1 A3
PQSensor MkVI Wiring Details