User’s Manual
for
PowerSight
PS2500
99 Washington Street
Melrose, MA 02176
Phone 781-665-1400
Toll Free 1-800-517-8431
Visit us at www.TestEquipmentDepot.com
R
ev for FW 4.43 / SW 3.4H
Copyright 2012 by Summit Technology
1
PowerSight is a registered trademark of Summit Technology, Inc.
T
he PowerSight model PS2500 is designed to comply with part
15, subpart B, of the FCC Rules for a Class A digital device.
odel PS2500 is designed to comply with the requirements of
M
IEC61010-1:2001 for a 600V input rating measurement category
IV, pollution degree II, double insulated electronic device.
M
odel PS2500 is manufactured by Summit Technology, Inc in the
U.S.A. The standard warranty period is 12 months from da te of
purchase. We encourage you to advise us of any defects of
design or manufacture of any of our products. We are dedicated
to your successful use of the product.
There are no user serviceable parts in your PowerSight
meter. Opening the case voids your warranty and may result in
present or future danger to users of the meter. The rechargeable
battery inside is a custom-designed battery pack that is only to be
replaced by authorized Summit Technology technical service
personnel.
Cleaning is to be done by use of a dry or damp piece of
cloth. Grease may be removed by light application of isopropyl
(rubbing) alcohol. Avoid the use of solvents, since they may
dissolve or weaken the plastic enclosure. Do not use water or
other conductive liquids since they may pose a safety risk.
Use of this equipment in a manner not specified by Summit
Technology can result in injury and voiding of warranty.
2
Table of Contents
ntroducing PowerSight ............................................................. 7
I
n a Hurry? --- The Basics of Operation .................................... 8
I
onnecting to PowerSight ......................................................... 9
C
Voltage Test Leads ....................................................................................... 9
Current Probes ............................................................................................ 10
Connections to PowerSight ....................................................................... 12
Introduction to Power Delivery Configurations ........................................ 14
Connecting to Single-phase Power .......................................................... 16
Connecting to 120 V Outlet Adapter Box ................................................. 17
Connecting to Multiple Single-phase Loads ............................................ 18
Connecting to Split-Phase (Two Phase) Power ..................................... 19
Connecting to Three-Phase Four-Wire (Wye) Power ............................ 20
Connecting to Three-Phase Three-Wire (Delta) Power ........................ 21
Connecting to Three-Phase Four-Wire Delta Power ............................. 22
Connecting to Three-Phase Grounded Delta Power ............................. 22
Connections Using 2 Current Approach .................................................. 23
Connecting to 3 CT / 3 PT Metering Circuit ............................................ 24
Connecting to 2 CT / 2 PT Metering Circuit ............................................ 27
Connecting to Open Delta (3CT / 2PT) Metering Circuit ....................... 27
Connecting to Line-To-DC (LDC) Converter Accessory ........................ 28
Measuring Multiple Parallel Conductors .................................................. 30
Measuring Currents Below the Range of the Current Probe ................ 32
T
urning PowerSight On ............................................................ 33
Connecting to Power .................................................................................. 33
Turning PowerSight On .............................................................................. 34
Turning PowerSight Off .............................................................................. 34
C
ommunicating with PowerSight ............................................ 35
Introduction ................................................................................................... 35
Step 1: Connecting to the Meter at the Operating System Level ......... 36
Step 2: Connecting to the Meter in PSM (the Application Level) ......... 37
sing Removable Memory Cards ............................................ 39
U
Introduction ................................................................................................... 39
Operation and Limitations .......................................................................... 39
Using the Memory Card Data with PSM .................................................. 40
V
erifying Connections Using PowerSight (SureStart
3
TM
) ........ 42
Importance of Verifying Connections and Wiring ................................... 42
Identifying the Power System .................................................................... 44
Error Summary ............................................................................................ 45
Identifying Errors ......................................................................................... 45
Checking out Connections using PSM ................................... 48
Checking Voltage Levels – Using PSM ................................................... 48
Check Voltage Phase Sequence – Using PSM ...................................... 49
Checking Current Levels – Using PSM .................................................... 50
Checking I Phase Sequence – Using PSM ............................................. 51
Checking Phase Lag Angle – Using PSM ............................................... 51
The “Next” Button .................................................................... 53
Overview ....................................................................................................... 53
Voltage Summary ........................................................................................ 53
Current Summar y ........................................................................................ 54
True Power (KW) Summary ....................................................................... 54
Apparent Power (KVA) Summ ary ............................................................. 55
True Power Factor Summary .................................................................... 55
Logging Summary ....................................................................................... 56
Time Summary ............................................................................................ 56
Identifying the Meter ................................................................................... 57
Identifying Operating Parameters ............................................................. 58
Measurement Types ................................................................. 59
Voltage Measurements .............................................................................. 59
Voltage Measurements in PowerSight ..................................................... 60
Voltage Measurements in PSM ................................................................. 60
Current Measurements .............................................................................. 62
Current Measurements in PowerSight ..................................................... 63
Current Measurements in PSM ................................................................. 64
Imbalance Measurements .......................................................................... 65
Imbalance Measurements in PSM ............................................................ 66
Power Measurements ................................................................................. 66
Power Measurements in PowerSight ....................................................... 67
Power Measurements in PSM ................................................................... 68
Power Factor Measurements .................................................................... 69
True Power Factor Measurements in PowerSight ................................. 71
Displacement P.F. and Phase Measurements in PowerSight .............. 72
Power Factor and Phase Measurements in PSM .................................. 72
Energy Measurements ............................................................................... 73
Energy Measurements in PowerSight ...................................................... 75
Energy Measurements in PSM ................................................................. 75
Cost Measurements .................................................................................... 76
Cost Measurements in PowerSight .......................................................... 76
4
Cost Measurements in PSM ...................................................................... 77
Demand Period Measurements ................................................................ 77
Demand Period Measurements in PowerSight ....................................... 78
Demand Period Measurements in PSM .................................................. 78
Frequency Measurements ......................................................................... 78
Frequency Measurements in PowerSight ................................................ 79
Frequency Measurements in PSM ........................................................... 79
Logging Summary on PowerSight ............................................................ 80
Time Summary on PowerSight ................................................................. 81
Time and Capacity Measurements in PowerSight ................................. 82
Time and Capacity Measurements in PSM ............................................. 82
Harmonic Measurements ........................................................................... 83
Harmonic Measurements in PowerSight ................................................. 85
Harmonic Measurements in PSM ............................................................. 85
Measurement Modes ................................................................ 87
Introducing Measurement Modes ............................................................. 87
Phase-Neutral vs Phase-Phase vs 2 Current Mode .............................. 87
Changing the Voltage Measurement Mode in PSM ............................... 89
50/60/400Hz vs DC vs Variable Frequency ............................................ 89
Changing the Frequency Measurement Mode in PSM .......................... 91
Always Positive Power versus Negative Power Allowed ...................... 91
Changing the Power Measurement Mode in PSM ................................. 92
Defining Inputs ............................................................................................. 93
Changing Input Ratios in PSM .................................................................. 94
Voltage & Current Waveforms ................................................. 96
Introduction ................................................................................................... 96
Saving Consumption Waveforms.............................................................. 96
Receiving Stored Consumption Waveforms ........................................... 97
Viewing Consumption Waveforms ............................................................ 99
Monitoring Power Consumption............................................ 104
Introduction ................................................................................................. 104
Basic Consumption Data Logging .......................................................... 105
Starting and Stopping Consumption Logging ....................................... 107
Receiving Consumption Data Log from PowerSight ............................ 108
Viewing Consumption Logs ..................................................................... 109
Deleting Log Data in the Meter ............................................................... 111
Custom Consumption Data Logging ..................................... 113
Introduction ................................................................................................. 113
Starting Data Logging ............................................................................... 113
Stopping Data Logging ............................................................................. 114
Setting the Consumption Logging Period .............................................. 115
5
Setting Measurement Types .................................................................... 115
Setting Measurement Modes ................................................................... 117
Saving and Retrieving Data Setups to File or PowerSight.................. 117
Loading Data Setups from the Memory Card (SD Card) .................... 118
Saving Data Setups to the Memory Card (SD Card) ........................... 119
Restoring the Default Setup ..................................................................... 119
Report Generator Software .................................................... 120
Introduction ................................................................................................. 120
Generating a Report ................................................................................. 120
Viewing a Report ....................................................................................... 122
Other Functions of PowerSight ............................................. 124
Calibrating PowerSight ............................................................................. 124
Administrative Functions .......................................................................... 124
Other Functions within PSM .................................................. 126
Introduction ................................................................................................. 126
Remote Control of PowerSight ................................................................ 126
Locating and Installing Software and Firmware .................................... 127
Setting up Administrative Features of PowerSight via PSM ............... 128
Setting Operational Features of PSM .................................................... 128
Putting it all Together (Monitoring for the First Time) ......... 129
Working with Graphs and Waveforms .................................. 132
General ....................................................................................................... 132
Reading Graphs and Waveforms............................................................ 134
Zooming and Panning .............................................................................. 135
Determining Log Capacity ..................................................... 138
Troubleshooting & Frequently Asked Questions (FAQ) ...... 140
Overview of the Remote Control Keypad .............................. 144
Compatibility Guide ................................................................ 146
Specifications* ........................................................................ 148
6
Introducing PowerSight
Congratulations on your decision to buy a PowerSight 2500! You
have just purchased one of the smallest and yet most powerful
instruments for measuring and analyzing electric power that
exists.
PowerSight is three instruments in one:
a power logger
a demand analyzer
a harmonics analyzer (with HAO option)
The philosophy of the product is to give you an instrument that
answers all your basic questions about electric power in a truly
convenient size at an attractive price
works effortlessly with all power systems
is nearly foolproof in setup and in getting results
makes reporting results quick and powerful.
The combination of the PS2500, our PowerSight Manager (PSM)
software, and our Report Writer software is truly remarkable.
If you are looking for a simple yet powerful tool that can be easily
and reliably installed and operated, one that provides for
comprehensive data analysis, you've found your tool of first
choice.
Whether your interest is in measuring
True power
Harmonics
Automated report writing
Viewing actual waveforms
Wiring and system analysis
PowerSight puts all the power in the palm of your hand!
*Note: Throughout this manual, whenever we refer to an individual
key of the keypad, we print the name on the key enclosed by
square brackets. For example, the “Volt” key is referred to as
[Volt].
7
In a Hurry? --- The Basics of Operation
If you're in a hurry, are experienced, and use good sense, you can
be up and running very quickly.
1. Review the section “
special attention to the safety warnings. You or the unit
can be hurt if you don't do things right!
2. Review the section on setting up your PS2500, “
Data Logging”. There are many different operating modes
and options. You don’t need to understand them all to get
started immediately, but it will increase your productivity to
understand the options available to you.
3. There is only one button available to press on the PS2500,
the [Next] button. Pressing this button will tell you what
connection errors may be present when you first turn the
unit on. It then displays summaries of measurements for
all three phases for your use.
4. To analyze data, send saved waveforms and data logs to
your computer using the supplied PSM software.
If you want to create a data log, review the section “
Together (Logging for the First Time)”. This will enhance your
understanding of logging and increase the likelihood that you will
have good results on your first attempt.
*Note: Throughout this manual, whenever we refer to the “Next”
button of the PS2500, it will be referred to as [Next].
Connections to PowerSight”, paying
Custom
Putting it all
8
Connecting to PowerSight
Voltage Test Leads
A Deluxe Voltage Probe set consisting of four leads is included
with each PowerSight. Each of the voltage test leads is 6 feet (2
meters) long, with safety banana jacks at one end and safety
plunger clamps at the other end. Each is labeled at both ends as
the V
1, V2, V3, or VN test lead. The safety plunger clamps have
telescoping jaws that you can actuate while keeping your fingers
three inches away from the actual metallic contact. Regular test
probes have conventional alligator jaw attachments that require
your fingers to be within one inch of the metallic contact. Also, the
method of attaching alligator jaws to a test lead can allow a gap in
the insulation between the lead and where they join. This is
where your thumb and finger are pressing while you actuate it.
For these reasons, to avoid unnecessary risk of shock,
only use test leads and clamps that are CE rated 1000V CAT
III (or 600V CAT IV) such as those supplied with your meter.
Another word of caution: Whenever connecting to a live
circuit, remember that the jaws of a voltage test lead are
much wider when they are open than when they are closed.
The potential to short or flash across two adjacent terminals
or wires is a constant danger when connecting to a live
circuit. Depending on the current capacity of the circuit
being shorted, arc flash and a deadly explosion of molten
material can result!
Once they are securely connected, the deluxe voltage leads are
safe for steady voltages of the 600 Vrms rating of PowerSight.
The clamps of the deluxe voltage leads are rated for 1000V
working voltage, measurement category III. This is equivalent to
measurement category IV for a working voltage of 600V, the rating
of the PS2500.
9
Summit Technology also sells a fused voltage lead set (order
DFV). The safety advantage of fused leads is that if a short
occurs through the insulation of a lead to ground, the fuse in the
handle should quickly blow out, preventing the lead from
vaporizing in an explosion of molten metal. The safety
disadvantage of fused leads occurs when the fuse is blown or is
removed. The user will measure 0 volts on a live circuit and may
be tempted to lower his safety awareness, possibly resulting in
shock or damage. The DFV probes are rated for 1000V,
measurement category III.
Current Probes
Summit Technology provides a variety of probes for your use.
They offer different measurement ranges, different sizes and
physical characteristics, and the ability to measure different types
of current.
Probes such as the HA1000 are excellent choices to use with
PowerSight because they support all the accuracy specifications
of the product. For instance, the HA1000 has an accuracy of
0.5% whereas many probes on the market have an accuracy of 23%. Also, the HA1000 maintains its accuracy for frequencies up
to 20,000 Hz. With our spectrum analyzer option (order FAO) it
can be used to measure frequencies up to 100,000 Hz riding on
the power line. This allows accurate current and power readings
of distorted waveforms, accurate readings of harmonics, and the
measurement of current transients that other probes would not
even detect.
Phase shift is also an important probe characteristic. The HA1000
has less than 1/2 degree of phase shift across the frequency
range when measuring currents above 50 amps and just 1.5
degrees at 5 amps. This means that instantaneous
measurements of power are highly accurate, regardless of the
waveform shape. The phase shift characteristics of most other
probes on the market are not this good. This results in erroneous
power and cost measurements and distorted waveforms. Please
Note: To diminish phase shift when measuring small currents, it is
advisable to clamp onto multiple "turns" of the same conductor in
order to increase the effective current being sensed.
10
The HA5 offers two advantages over the HA1000, but these
advantages come at a cost. Its advantages are that the HA5 is a
very small size (5.25 × 2.00 × 1.35 inches) and second, it offers
much greater sensitivity since it reads currents from 20 milliamps
to 5 amps (as compared to the HA1000 measuring 1 - 1,000
amps). The tradeoff is accuracy. The probe has a basic accuracy
of 2% and its phase shift varies by frequency and by amplitude.
All told, you can expect to measure current to a nominal 3%
accuracy and power and cost to a nominal 6% accuracy using the
HA5 probe.
The HA1 00 pr obe is the same compact size as the HA5. The
HA100 measures from 0.1 to 100 amps at 2% accuracy. It is a
good choice over the HA1000 if you wish to lock PowerSight, its
leads, and current probes inside a power panel that you are
monitoring. It is also a good choice when small size is important
while measuring currents above 5 amps. The HA100 is a popular
choice for a second set of probes.
For very large currents and large bus bars, we offer the eFX6000.
The eFX6000 is a "flex" type probe. It consists of a flexible tube
about 0.4 inch in diameter and 24 inches long (a 36 inch version is
also available). The ends of this tube snap together around a
conductor to sense the current. Flex probes are very handy when
space is tight, when multiple cables must be clamped around, or
when a bus bar is present. They are also lighter than clamp-on
probes. The flexible tube creates a circle with an inside diameter
of 7 inches. This circle can be deformed into various shapes to
accomplish your measurement goals. The basic accuracy of the
flex probe is good, measuring from 1 to 6000 amps (across two
ranges) within 1% accuracy. However, readings can vary as
much as 2% depending on the position of the flex probe while
connected. Position the flexible portion of the probe around the
conductor so that the cable from the probe drops straight down
and the place where the ends snap together is at a right angle
with the conductor and not touching it. The frequency response of
flex probes is very good, but phase shift increases with frequency.
Our eFX6000 is powered by the meter, so no batteries are
required.
11
You must use added caution when connecting an FX
series current probe around exposed conductors and bus
bars since you must pull the tube around the conductor and
thus get your hands and arms closer to it than when using
HA series clamp-on type current probes. Wise practice
dictates that you use high insulation protection on hands and
forearms in these circumstances or deactivate the circuit.
The DC600 probe is used for AC current measurements from 5 to
400 amps and DC measurements from 5 to 600 amps. It offers
accuracy of 2% ±1 amp from 5 - 400 amps and 3% accuracy for
DC from 400-600 amps. This probe relies on Hall effect
technology and its output varies slightly over time. Therefore, a
zero level adjustment is provided on the probe's handle for initial
zeroing before each measurement session. The probe can clam p
around one cable up to 1.18 inch diameter or two cables of up to
0.95" diameter. Unlike other manufacturers’ DC probes, ours do
not require batteries for them to run.
New probes and adapters are introduced regularly, so if you have
a special need, give us a call.
Please Note: Always inspect the metal surfaces of clamp-on
probes before use. Clean them with a rag or sand them with
fine sand paper and then slightly oil the surface. Any dirt or
rust will affect the accuracy of the measurements!
Connections to PowerSight
Voltage test leads plug into the top end of PowerSight. Each test
lead of the Deluxe Voltage Test Lead set is labeled (V
V
3) and each jack is similarly labeled (VN, V1, V2, or V3).
N, V1, V2, or
Note: The VN test lead is a different color from the other
leads (black). Similarly , t h e V
N jack on PowerSight is a
different color from the other ones (black). Connecting
anything other than neutral or ground to the V
N jack can
jeopardize your safety, the functioning of the unit, and the
accuracy of the unit.
12
Current probes plug into the top end of PowerSight, just above the
voltage inputs. Each current probe is labeled (I
each jack is similarly labeled (I
1, I2, I3, or IN). When plugging a
1, I2, I3, or IN) and
current probe into PowerSight, the flat side of the plug should be
facing upwards so the label is readable. This will align it properly
for plugging into the PowerSight case.
Clamp-on probes have a correct orientation in which to attach
them. On most probes' head, there will be an arrow pointing in the
direction of the conductor being measured. When clamped onto
I
1, I2, I3, or IN, the arrow should point along the conductor from the
power source towards the load. If the current probe is connected
backwards, its waveform will appear upside-down when you
upload waveforms, it may be slightly less accurate in its current
readings, and, most importantly, if you operate in positive/negative
power measurement mode, power readings will be disastrously
wrong.
13
Introduction to Power Delivery Configurations
Figure 1 presents
most common power
delivery
configurations.
PowerSight is able to
measure voltage,
current, power, power
factor, and more for
all of these systems.
Figure 1A presents
the normal singlephase and split-phase
service as found in a
residential service. In
North America, V
and V
2N are 120V
and are 180 degrees
out of phase with
each other. When
heavier loads are
encountered, V
(240V) is used by delivering both hot voltages to the load. Neutral
provides the current return path. If the load is balanced, there will
be relatively little neutral current. Refer to figures
various ways to connect to single-phase and split-phase power
service.
Figure 1B presents normal three-phase “wye” power service.
Voltages are usually measured from phase-to-neutral. Neutral
provides the current return path. If the load is balanced, there will
be relatively little neutral current. Refer to
connect to a three-phase wye power service.
Figure 1C presents normal three-phase delta service. Voltages
are usually measured from phase-to-phase. In North America,
service is usually supplied as 120V, 240V, 480V, 600V, 4160V, or
12,500V. In most of the world, phase-to-phase service is usually
supplied as 381V, 5,716V, or 11,431V. Summit Technology has
voltage probes for direct connect to all of these services. Refer to
1N
12
2, 3, 4, and 5 for
figure 6 for how to
14
figure 7 for how to connect to a delta power service. When there
is no access to measuring one of the currents,
figure 8 presents
the 2 current approach for measuring power. This approach is
also useful for measurement of an open delta circuit as described
in Connections to an Open Delta Circuit (2PT/3CT)
figure 10.
Although phase-to-phase is the normal voltage measurement
mode for this service, PowerSight can be set to phase-to-neutral
(even though the neutral is not connected). In this case, the
measured voltages will be phase-to-metering-neutral (such as V
V
1N = 277V for a 480V service) and all other measurements will
1N
also be correct.
Figure 1D presents three-phase
four-wire delta service. In this
configuration, a neutral is supplied from a point midway between
two phases. This is handy when 240V delta is supplied. V
V
3N supply conventional 120V single-phase power and V1N
2N and
provides 208V, if needed. In this configuration, depending on
what you are measuring, you may choose to measure in phase-tophase mode or in phase-to-neutral mode.
Figure 1E presents
grounded delta service. This configuration is
actually not very common. It can be attractive to use if an
electrically isolated three-wire delta service is available and there
is a need to provide the power a long distance away at a private
facility (such as a saw mill). By grounding one of the phases at
the source, the cost of supplying one of the phases to the remote
site is saved. A motor at that site would be connected to phase 1,
phase 2, and earth ground. There is increased danger in this
configuration over normal isolated delta service since the
reference to ground is intentionally an excellent conductive path.
Nevertheless, PowerSight will provide the desired measurements
in this configuration.
15
Connecting to Single-phase Power
Figure 2 presents
the basic
connections to a
single-phase
system.
Be
sure to follow the
safety warnings of
the previous
sections before
making the
connections.
Clamp your phase 1
current probe onto
the "Hot" wire.
Make a metallic
connection to
neutral with the V
N
voltage lead.
Similarly connect
the V
1 lead to "Hot".
Since voltage now comes into PowerSight on V
sensed by I
1, the power and power factor for this single-phase
1 and current is
system will be available as phase 1 power and phase 1 power
factor.
Caution: Until you are certain that your voltage
connections to PowerSight are correct, disconnect any
current probes. This is because PowerSight and all of its
connections float at the potential of V
N. If VN is "hot", there
may be a breakdown through the insulation of any attached
probes.
Helpful Hint: How to Identify the "Neutral" lead.
Normal single-phase wiring follows the convention of "neutral"
being the white wire, "hot" being the black wire, "hot2" being the
red wire, and "ground" being the green wire. If the wiring and your
16
connections to PowerSight are as shown in figure 2, V1N will be
some relatively large number like 120 volts and V
3N will be a small
voltage like 3 volts. If you then reverse the ground and neutral
leads, V
"neutral" are reversed, then V
1N will now read slightly less, like 117 volts. If "hot" and
3N will become a large number, like
117 volts.
Connecting to 120 V Outlet Adapter Box
The 120 V
Outlet Adapter
Box
accessory
(order number
120ADP)
offer s a safe,
convenient,
and accurate
way to monitor
voltage in a
commercial
setting or to
evaluate
power usage
of appliances.
Figure 3
presents the
connections to
the Adapter
Box. Simply
plug the
adapter box
into a wall
socket and then attach the voltage and current leads into
PowerSight. Each lead is labeled to eliminate errors in
connections.
Note: Make sure that the hot and neutral wiring being
measured is not reversed. If so, PowerSight and its
attachments will "float" at 120 V.
17
Note: The 120ADPa is rated for continuous duty of up to
15 Arms. Do not exceed this continuous load.
To evaluate the power usage of an appliance, simply plug the
appliance into the top of the 120 V Outlet Adapter Box after the
other connections have been made and verified. Even without an
appliance plugged in, the adapter box offers a convenient means
of checking for transients or analyzing the harmonic content of the
incoming voltage.
Connecting to Multiple Single-phase Loads
Figure 4
presents a
means to
monitor 3
single-phase
loads
simultaneously.
The loads must
all share the
same neutral
voltage
connection. If
the loads run
off th e same
line voltage,
connect V
and V
same "hot"
wire. I
I
3 serve the 3
loads. This
approach can
also be used to
evaluate the
current of a 4th
load, but the power used by that load will not be calculated.
1, V2,
3 to the
1, I2, and
18
In this configuration, the voltage, current, and power of each load
can be displayed directly or graphed on your PC using our PSM
software.
Connecting to Split-Phase (Two Phase) Power
Fig 5 shows
the
recommended
connections to
a split-phase
system as
found in
commercial
and residential
facilities, when
measuring the
supply to two
single phase
loads. There
are two "Hot"
wires 180
degrees out of
phase with
each other and
sharing the
same neutral.
Appliances
such as ovens
that require
240V will span
across both hot wires. When evaluating the power for a load
spanning the two phases, remove the V
affect the power factor readings of each phase.
In this configuration, a reading of V
hot2-neutral. I
N does not need to be connected and VN should not
be connected when the load spans the two phases. The power
associated with one hot is measured as phase 1, the power of the
other hot is measured as phase 2. In phase-neutral measurement
mode, the voltage readings will be from hot-to-neutral. If you
N voltage lead since it may
1N is of hot-neutral and V2N is
19
change the measurement mode to phase-phase, V12 will be the
hot-to-hot voltage that serves the high power appliance.
Connecting to Three-Phase Four-Wire (Wye) Power
Figure 6
presents the
recommended
connections to
a three-phase
system with
voltages
referenced to
neutral, a
"phase-neutral"
or “three-phase
four-wire wye”
configuration.
Be sure
to follow the
safety
warni ngs of
the previous
sections
before making
the
connections.
Although the current of each phase is carried by neutral, neutral
current is generally relatively small since the currents of the 3
phases largely cancel each other in the neutral leg. In a perfectly
balanced system the current in neutral would be zero.
In a wye sys tem, each phase is essentially independent of each
other. For this reason, the power factor of each phase has direct
meaning, but the total power factor is less meaningful.
Most commercial wiring and newer industrial wiring is in this wye
configuration.
20
Connecting to Three-Phase Three-Wire (Delta) Power
Figure 7 presents
the recommended
connections to a
three-phase
system with
voltages
referenced to
each other
instead of to
neutral. This is a
"delta", "phasephase", or “threephase three-wire”
configuration.
Be sure to
follow the safety
warnings of the
previous
sections before
making the
connections.
Please Note: Do not connect the V
measuring in phase-phase measurement mode. This may
affect the measurements associated with individual phases.
In a delta configuration, current flowing in each phase is due to the
interaction of 2 different voltages. For instance I
resultant of V
12 and V31. Normally, there is no way to determine
what portion of the current is due to which voltage. For this
reason, only the total power and total power factor have definite
meaning in a delta system. However, comparing the power
factors of each phase can be valuable for spotting a connection
problem or problem with the load.
Delta power is common in motors and older industrial sites.
N input to anything when
1 current is the
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A variation of delta is “four-wire” (or “ce nter-tapped”) delta (see
figure 1D). In this configuration, if the main interest is in
measuring phase-neutral voltage, then connect the neutral voltage
to the neutral input for more accurate voltage readings
Connecting to Three-Phase Four-Wire Delta Power
Figure 6 presents the recommended connections to a three-phase
delta system where a neutral is provided from the center of one of
the phases.
Be sure to follow the safety warnings of the previous
sections before making the connections.
This type of system allows delivery of both three-phase and
single-phase power. The three-phase power is typically 240V for
running motors. The dual single-phase power is typically 120V for
running lights and small equipment, from one power service. It
also provides 208V. Depending on what you intend to monitor, it
may be appropriate to set PowerSight in phase-phase voltage
measurement mode (to monitor three-phase l oads or t o l ook at
total power) or in phase-neutral voltage measurement mode (to
monitor single phase loads). Although the selection of voltage
measurement mode affects what voltage levels are displayed and
recorded (phase-phase versus phase-neutral), it does not affect
the power and power factor calculations.
Connecting to Three-Phase Grounded Delta Power
Figure 7 presents the recommended connections to a three-phase
system with one phase tied to ground. No connection is made to
the neutral input. One of the phases originates from ground.
Be sure to follow the safety warnings of the previous
sections before making the connections.
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Connections Using 2 Current Approach
In the previous
sections, the
approach used
to measure
power has been
based on
determining the
power of each
phase and then
summing them
to get the total
power. The 2
current
approach
(figure 8) allows
you to
determine the
total power from
measuring only
2 of the 3
currents and
combining them
with the 3
voltages of the
three-phase circuit. The disadvantage of this approach is that you
cannot determine the power, power factor, or VA of each
individual phase and, of course, you cannot record the current of
one of the active phases.
A necessary use for this type of connection is to measure utility
power where only two metering CTs and three PTs are provided.
After hooking up to the CTs and PTs, you enter the input ratios
into PowerSight (see the
record the correct values (the values on the primary side of the
transformers).
A different motivation for using this type of connection is to save
time and money. By only connecting to 2 of the 3 currents, a
small amount of time can be saved. The frugal user appreciates
Setting Input Ratios section) in order to
23
this approach because he can save the cost of one current probe
( )( )
total ab a cb c
W VI VI= ×+ ×
∑∑
when buying a system in order to measure total power. Another
motivation occurs in situations where one of the phases cannot be
measured due to accessibility.
This approach is also called the “2 wattmeter approach” because
it mimics how two single-phase wattmeters can be used to
measure total three-phase power. The equation that it depends
on is:
. This equation is true regardless
of the harmonic content of the voltages and currents present. A
few words of caution are required, however. First, a voltohmmeter cannot be used for this calculation. That is because
the equation depends on the instantaneous products of voltage
and current. That is normally quite different from the product of
the RMS voltage and RMS current. Second, a single-phase
wattmeter should not be used for this calculation since conditions
normally change second by second and hence adding the watts of
two different setups will, at best, give a “feel” for the correct true
power. Lastly, it is more important to make the connections
correctly in this approach since an error will not be obvious and
there is no way of recovering to an educated guess of the correct
power reading.
Refer to the
section for how to operate the unit in 2 current probe mode.
Phase-Neutral vs Phase-Phase vs 2 Current Mode
Connecting to 3 CT / 3 PT Metering Circuit
Sometimes it is helpful to monitor a load indirectly, by connecting
PowerSight to a metering circuit in front of the load. A few
circumstances where this is the case are:
the CTs (current transformers) and PTs (potential
transformers) of the metering circuit are readily accessible for
connecting to, whereas the actual load carrying cables are not
the conductors carrying the load are physically too large for
your current probes to fit around them
the load current is too large to be read by the current probes
you have
the voltage delivered to the load exceeds the 600V insulation
limit of the current probes
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the voltage delivered to the load exceeds the 600Vrms rating
of PowerSight and you do not have other high voltage probes.
A typical
metering
circuit showing
PowerSight
connected is
shown in
figur e 9. This
circuit has
three CTs and,
if higher
voltage is
present, may
have three
PTs. It is
typical for
metering a
three-phase
four-wire wye
type service.
The currents
flowing to the
load are
considered the
“primary
currents”.
Those currents
are “stepped
down” by each
CT to a
“secondary
current”
according to
the ratio of the
CT printed on
its rating plate. A typical value would be 600:5 (120:1). The
output of each CT must have some burden across it for the
secondary current to flow. The current probes of PowerSight are
clamped around the secondary of each CT. Make sure to use
current probes that are suited for accurate measurement in the 0-
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5 amp range. The HA5 is best for this. The HA1000 or HA100
may be acceptable, depending on the current level.
Once the current probes are attached, it is best to set the input
ratios for each of the current probes (see the
Setting Input Ratios
section). This will allow the displayed values and logged values to
reflect the primary current level instead of the secondary current
level. This in turn allows accurate power and cost readings
without having to multiply the results times some ratio.
Remember that these ratios are reset to 1:1 whenever PowerSight
is turned off.
Similarly, the PTs take a primary voltage and step it down to a
secondary value. If the primary voltage is below 600Vrms, you
will not need to hook up to the PTs (in fact, there will probably be
none present). The ratio of the stepping down of the voltage will
be printed on the rating plate of the PT. Typically this would be
2400:120 (20:1). As with the CTs, this ratio should be entered into
PowerSight (see the
Setting Input Ratios section) to simplify
interpreting the results.
26
Connecting to 2 CT / 2 PT Metering Circuit
Figure 10 shows
recommended
connections to a
metering circuit
with only 2 CTs
or 2 PTs. This
type of metering
circuit may be
preferable when
cost is an issue
(less instrument
transformers are
used) or when
metering a delta
service with no
reference to
neutral. The
discussion of the
previous section
(
Connections To
a 3 CT / 3 PT
Metering Circuit)
applies to this
circuit as well,
with one
important
exception. If
you clamp onto
the CTs, rather
than clamping
onto each of the primary currents directly, PowerSight must be
operating in the 2 Current Probe mode of operation (see the
Phase-Neutral vs Phase-Phase vs 2 Current Mode section).
Connecting to Open Delta (3CT / 2PT) Metering Circuit
In the open delta configuration, two PTs and 3 CTs are available.
Make the voltage connections as shown in figure 10 of the
Connections to a 2CT / 2PT Metering Circuit section. For current
27
connections, connect the phase 1 and phase 3 probes as shown
in figure 10 and attach the phase 2 current probe to the phase 2
CT. You will not need to operate in the 2 Current Probe mode of
power measurement since there are 3 currents being monitored.
Connecting to Line-To-DC (LDC) Converter Accessory
The Line-To-DC Converter accessory (order either LDC2 or
LDC4) converts the voltage that is being monitored into DC
voltage to run and charge PowerSight. The applications of this
option are:
Electrical room monitoring where a 120V outlet jack is not
available for your charger
Monitoring where an extension cord from a 120V outlet jack
would be a safety hazard
Monitoring on a rooftop, power pole, or power pad
Reliable charging for the meter when there is concern that an
available 120V outlet jack may be switched off by other
personnel
Simplified monitoring connections (no need to think about
powering PowerSight when installed inside a CASW weatherresistant case.
Figure 11 shows the correct method of connecting the LDC to
PowerSight. The LDC comes with two long red input leads that
end with a stackable safety banana plugs. These stackable plugs
are to be inserted directly into two of the inputs of PowerSight. If
you are monitoring power without a neutral, we recommend
plugging them into the V
present, we recommend plugging them into the V
In any case, there needs to be a potential between them of at
least 100 Vrms and no more than 500 Vrms from 50 Hz or 60 Hz
power.
The LDC4 is a more powerful version of the LDC2. The LDC2 can
be used with the PS2500, PS3500, and PS250. The LDC4 can be
used with the PS2500, PS3500, PS4500, PS4000, and PS250.
1 and V2 inputs. If an external neutral is
1 and VN inputs.
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The LDC also
comes with inline fuse
assemblies
plugged into
the stackable
plugs. These
red assemblies
contain 1000V
fuses. They
provide
protection if a
short should
occur in the
LDC. The two
voltage leads
that would
normally be
plugged into
PowerSight
are plugged
into the loose
ends of the inline fuses. At this point, PowerSight is ready to measure voltages
as usual and the LDC is connected in parallel to two of the inputs
of PowerSight. You may wish to remove the in-line fuse
assemblies, plug your voltage leads directly into the stackable
plugs, and plug the in-line fuse assemblies between the loose
ends of the voltage leads and the voltage clips. This provides a
connection that is electrically equivalent to the normal connection,
but the fuses are physically as close to the power source as
possible. The advantage of this approach is that if one of the
voltage leads gets shorted to ground (perhaps from being cut by a
panel door), a fuse quickly blows, providing added protection.
Note: Do not use the LDC without the in-line fuses being
connected between it and the power source. The fuses are
the only circuit protection for the LDC.
When the input side of the LDC is fully connected properly, plug
the long DC output plug into the DC input jack of PowerSight. The
29
red charging indicator near the jack will light up if everything is
operating and connected properly.
Note: If a fuse is burned out or missing, it will appear
that there is no voltage at the source. Verify that the fuses
are working properly before assuming that the source is
dead. Injury may occur if you wrongly assume that the
source is deactivated.
Measuring Multiple Parallel Conductors
A common problem with
measuring large currents
arises when the current of
each phase is carried by
several parallel conductors.
For instance the phase 1
current may be carried in 4
parallel conductors, as are
phases 2 and 3, resulting in
12 conductors to measure.
In this case, the work-around
is to clamp onto just one of
the conductors of each
phase and enter an input
ratio to record the correct
total current of each phase.
A fast way of doing this is to
enter an input ratio of 4 : 1
for each phase in the example of 4 parallel conductors. This may
offer adequate accuracy for your needs. However, experience
shows that although the current in each conductor of the same
phase is similar in size, they are typically NOT identical.
Overcoming the problem of unequal currents in parallel cables
takes a few steps to do it accurately.
1. Put a different probe on each conductor of a given phase and
then viewing the currents of each probe simultaneously (see
the
Checki ng Current Levels – Using Checkout Connections
section).
30
2. Start monitoring for 10 seconds or so and then stop monitoring
(see the
Starting Data Logging and Stopping Data Logging
sections).
3. Press the [Current] key and then the [More] key four times to
view the average current for phase 1 (which is actually just
one of the conductors of one of the phases). Write it down.
4. Press the [Current] key and then the [More] key four times
again to view the average current for phase 2. Write it down.
5. Repeat these actions in order to get the average current of
each of the conductors for the same time period.
6. Find the total of the average currents of each of the
conductors of the same phase.
7. Divide the total of the average currents into the average
current of conductor you wish to connect to during the actual
monitoring session. This yields the portion of the total current
that flows through the conductor that will be measured.
8. Set the input ratio of the phase being measured to the number
determined in the previous step. For instance if the total of the
average currents was 1000 amps and the average current of
the probe on the conductor you wish to use during the actual
monitoring session had an average of 26 amps, then enter an
input ratio for that phase of 0.26 : 1.
9. Perform steps 1 through 8 for each phase.
10. Now connect each probe to the chosen conductor of each
phase and begin monitoring. All the readings and logged
values will be substantially correct.
31
Measuring Currents Below the Range of the Current Probe
A problem with measuring smaller currents arises when the
current to be measured is below the range of the current probe. In
such cases, the current may not be read or the reading may be
inaccurate. In addition, any waveforms that are captured will have
excessive noise on them.
If you are using a flexible current probe, you can simply wrap it
around the conductor twice in order to double the magnetic field
strength. This can get it in the measurement range and it boosts
the signal to noise ratio. If you use this method, set the input ratio
for the current probe to 1 : 2 (see the
PowerSight section).
If the current to be measured is
small, it may be acceptable to
open the circuit and insert an
extra length of wire that is
wound up into a coil of 10 turns.
Clamping your current probe
around this extension coil will
boost the signal strength 10
times and allow accurate
reading of small currents. If you
use this method, set the input
ratio for the current probe to 1 :
10 (or however many turns there
are in the coil).
Changing Input Ratios in
32
Turning PowerSight On
Connecting to Power
Although PowerSight comes with Ni-Cad rechargeable batteries,
those batteries are intended to keep PowerSight functioning
during limited power failures and to allow quick measurements
without the bother of always having to find a 120 Vrms source.
When fully charged, the batteries can power the unit for up to 10
hours.
For longer usage and to recharge the batteries, your unit has been
supplied with a wall-mount power supply. This power supply
cannot be used with the model PS3000 and the PS3000 power
supply cannot be used with the PS2500. To use this power
supply, simply plug it into any 120 Vrms source (use the model
CHG4 charger for 120Vrms and the model CHG1 for 220V) and
then plug its barrel-type plug into the 12 VDC input jack on the
right side of PowerSight. If charging voltage is available, an LED
indicating light will immediately shine through the hole located to
the right of the input power jack. Allow 12 hours to fully charge
the unit (though 8 hours is adequate for most usage).
If you wish to operate PowerSight without being tethered to a
power outlet, the Line-to-DC converter accessory (order LDC2 or
LDC4) offers the ability to power a PS2500 directly off the line
voltage being monitored. It works with 50 Hz and 60 Hz power,
operating off 100 to 480 Vrms input, single-phase or three-phase.
All this versatility is obtained without setting switches or changing
connections. The LDC is especially convenient when monitoring
in areas where 120 V outlets are not readily available. The LDC4
is a more powerful version of the LDC2 and can power any of our
meters (except the PS3000).
If you need to operate the LDC4 off of 600V phase-to-phase
service, recommended procedure is to connect one input to a hot
phase and the other input to neutral (if present).
33
The internal batteries are automatically charged when the wallmount supply is connected to the unit (or when PowerSight is
connected to the LDC accessory).
The internal batteries are not to be replaced by the user. Only
batteries provided by Summit Technology are to be used in
PowerSight.
Turning PowerSight On
Simply press the green on/off button at the lower right of the
keypad on the front panel and PowerSight will be operating
(pressing the button again, turns the unit off). The message that
the meter is analyzing the connections to the meter will appear for
a few seconds and then the results of the analysis will appear.
Please note that turning PowerSight on does not automatically
start monitoring and logging. Refer to the
(Monitoring for the First Time) section for how to start monitoring
and logging.
Putting it all Together
Turning PowerSight Off
To turn PowerSight off, simply press the the green on/off button at
the lower right of the keypad on the front panel. This provides a
graceful software/firmware shutdown. If pressing the button briefly
does not turn the meter off, press and hold the push-button down
for 3 seconds to force a hardware shutdown. If this is a recurring
problem, contact
support@powersight.com.
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