Summit Technology PowerSight PS4550 User manual

1
Summit Technology, Inc.
2246 Monument Blvd
Pleasant Hill, CA 94523
Tel: [phone]
[e-mail]
www.powersight.com
Rev for FW 7.2J / SW 4.1J
Copyright 2022 by Summit Technology
User’s Manual
for
PowerSight
PS4550

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PowerSight is a registered trademark of Summit Technology, Inc.
The PowerSight model PS4550 is designed to comply with part
15, subpart B, of the FCC Rules for a Class A digital device.
Model PS4550 is designed to comply with the requirements of
IEC61010-1:2001 for a 1000V input rating measurement category
III, pollution degree II, double insulated electronic device.
Model PS4550 is manufactured by Summit Technology, Inc in the
U.S.A. The standard warranty period is 12 months from date 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.

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Table of Contents
Introducing PowerSight ............................................................. 8
Connecting to PowerSight ......................................................... 9
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
Connections to a 3 CT / 3 PT Metering Circuit .................................. 24
Connections to a 2 CT / 2 PT Metering Circuit .................................. 27
Connections to an 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
Turning PowerSight On ............................................................ 33
Connecting to Power ................................................................................ 33
Turning PowerSight On ........................................................................... 34
Turning PowerSight Off ........................................................................... 34
Communicating with PowerSight ............................................ 35
Introduction ................................................................................................ 35
Connecting Via Bluetooth (Windows 7/8/10/11) ................................ 36
Connecting Via USB cable (Windows 7/8/10/11) ............................... 39
Using Removable Memory Cards ............................................ 40
Introduction ................................................................................................ 40
Operation and Limitations ...................................................................... 40
Downloading Data via Memory Card .................................................... 41
Verifying Connections Using PowerSight (SureStartTM) ........ 43
Importance of Verifying Connections and Wiring ............................ 43
Identifying the Power System ................................................................ 45
Error Summary .......................................................................................... 46
Identifying Errors ...................................................................................... 46
Checking Connections using PSM-A ...................................... 49
Checking Voltage/Current Levels – Using PSM-A ............................ 49
Checking I Phase Sequence – Using PSM-A ..................................... 50
Checking Phase Lag Angle – Using PSM-A ....................................... 51

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Measurement Types ................................................................. 52
Voltage Measurements ............................................................................ 52
Voltage Measurements in PowerSight ................................................ 54
Voltage Measurements in PSM-A.......................................................... 55
Current Measurements ........................................................................... 57
Current Measurements in PowerSight ................................................ 58
Current Measurements in PSM-A.......................................................... 60
Imbalance Measurements ....................................................................... 61
Imbalance Measurements in PSM-A .................................................... 63
Power Measurements .............................................................................. 63
Power Measurements in PowerSight ................................................... 64
Power Measurements in PSM-A ............................................................ 65
Power Factor Measurements ................................................................. 66
True Power Factor Measurements in PowerSight ............................ 68
Displacement P.F. and Phase Measurements in PowerSight ........ 71
Power Factor and Phase Measurements in PSM-A .......................... 72
Energy Measurements ............................................................................. 73
Energy Measurements in PowerSight ................................................. 74
Energy Measurements in PSM-A .......................................................... 75
Cost Measurements .................................................................................. 75
Cost Measurements in PowerSight ...................................................... 76
Cost Measurements in PSM-A ............................................................... 77
Demand Period Measurements ............................................................. 78
Demand Period Measurements in PowerSight .................................. 78
Demand Period Measurements in PSM-A ........................................... 78
Frequency Measurements ...................................................................... 79
Frequency Measurements in PowerSight ........................................... 80
Frequency Measurements in PSM-A .................................................... 80
Duty Cycle / Power Cycle Measurements ........................................... 81
Duty Cycle / Power Cycle Measurements in PowerSight ............... 82
Time and Capacity Measurements ....................................................... 83
Time and Capacity Measurements in PowerSight ............................ 84
Time and Capacity Measurements in PSM-A ..................................... 85
Harmonic Measurements ........................................................................ 86
Harmonic Measurements in PowerSight............................................. 88
Harmonic Measurements in PSM-A ...................................................... 88
Swells (Surges) and Inrush Measurements ....................................... 89
Dips (Sags) Measurement ....................................................................... 89
High-Speed Transient Measurements ................................................. 90
Measurement Modes ................................................................ 91
Introducing Measurement Modes ......................................................... 91
Phase-Neutral vs Phase-Phase vs 2 Current Mode.......................... 91
Changing the Voltage Measurement Mode in PowerSight ............. 93
Changing the Voltage Measurement Mode in PSM-A ...................... 93
50/60/400Hz vs DC vs Variable Frequency ......................................... 94

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Changing the Frequency Measurement Mode in PowerSight ....... 95
Changing the Frequency Measurement Mode in PSM-A ................ 96
Always Positive Power versus Negative Power Allowed ............... 96
Changing the Power Measurement Mode in PowerSight ............... 97
Changing the Power Measurement Mode in PSM-A ........................ 98
Defining Inputs .......................................................................................... 98
Changing Input Ratios in PowerSight ............................................... 100
Changing Input Ratios in PSM-A ........................................................ 100
Voltage & Current Waveforms ............................................... 102
Introduction .............................................................................................. 102
Saving Consumption Waveforms ....................................................... 102
Receiving Stored Consumption Waveforms .................................... 104
Viewing Consumption Waveforms ..................................................... 105
Monitoring Power Consumption............................................ 109
Introduction .............................................................................................. 109
Basic Consumption Data Logging ...................................................... 110
Receiving the Data Logging Session from PowerSight ................ 113
Viewing the Data Logging Session in PSM-A .................................. 114
Working with Graphs and Waveforms .................................. 115
Presentation of the Graph ..................................................................... 115
Reading Graphs and Waveforms ........................................................ 116
Zooming and Panning ............................................................................ 119
Custom Data Logging ............................................................ 121
Introduction .............................................................................................. 121
Starting Data Logging ............................................................................ 121
Stopping Data Logging .......................................................................... 122
Setting the Data Logging Period ......................................................... 123
Setting Measurement Types ................................................................. 124
Setting Measurement Modes ............................................................... 125
Saving & Retrieving Setups to File or PowerSight in PSM-A ...... 125
Loading Data Setups from the Memory Card (SD Card) ............... 126
Saving Data Setups to the Memory Card (SD Card) ...................... 127
Restoring the Default Setup ................................................................. 127
Monitoring Swell/Dip/Inrush .................................................. 128
Introduction .............................................................................................. 128
Swell/Dip Event Log ............................................................................... 129
Swell/Dip RMS Graph Log ..................................................................... 131
Swell/Dip Event Waveforms ................................................................. 132
Setting the Swell/Dip Trigger Thresholds in PowerSight ............. 132
Setting the Swell/Dip Trigger Thresholds in PSM-A ...................... 134
Monitoring High-Speed Transient Events ............................. 136
Introduction .............................................................................................. 136
Transient Event Log ............................................................................... 137
Transient Event Waveforms ................................................................. 138
Setting the Transient Trigger Thresholds in PowerSight ............. 139

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Setting the Transient Trigger Thresholds in PSM-A ...................... 140
Allocating Memory within PowerSight .................................. 142
ReportWriter Software ............................................................ 144
Introduction .............................................................................................. 144
Generating a Report ............................................................................... 144
Viewing a Report ..................................................................................... 147
TestPlan Manager in PSM-A .................................................. 149
What is TestPlan Manager .................................................................... 149
How Does it Work? ................................................................................. 149
Opening an Existing TestPlan in PSM-A ........................................... 150
Create a New TestPlan in PSM-A ........................................................ 151
Using TestPlan Manager with Powersight ........................................ 155
Performing the Tests .............................................................. 155
Retrieving the TestPlan Data in PSM-A ............................................. 156
Opening TestPlan Data in PSM-A ....................................................... 159
Other Functions of PowerSight ............................................. 159
Calibrating PowerSight .......................................................................... 159
Setup Functions ...................................................................................... 160
Administrative Functions ...................................................................... 161
Other Functions within PSM-A .............................................. 163
Introduction .............................................................................................. 163
Remote Control of PowerSight ............................................................ 163
Locating and Installing Software and Firmware ............................. 164
Setting up Administrative Features of PowerSight via PSM-A ... 166
Putting it all Together (Monitoring for the First Time) ......... 166
Troubleshooting & Frequently Asked Questions (FAQ) ...... 168
Frequency Analysis Option ................................................... 173
Overview of the Keypad Functions ....................................... 174
Compatibility Guide ................................................................ 175
Specifications* ........................................................................ 177

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Introducing PowerSight
Congratulations on your decision to buy a PowerSight PS4550!
The PS4550 is a complete upgrade of the previous PS4500.
Some of the new benefits and features are:
 New USB Communications
 Faster Bluetooth Communications
 Faster SD card transfers
 Unbalanced voltage & current measurements
 Testplan Manager Support
The PS4550 is a complete solution for the measurement and
analysis of all aspects of power:
 High-speed transient analysis
 Swell/Dip analysis
 Harmonics analysis
 Demand analysis
 Data logging
 Automated report writing
 Wiring and system analysis
The philosophy of the product is still the same, to give you an
instrument that answers your questions about electric power in a
truly convenient size at an attractive price, now with more
features!
Whether your interest is in
 The quality of incoming power,
 Managing power consumption, or
 Maintaining and comparing equipment
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 “Voltage” key is referred to as
[Voltage].

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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 V1, 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,
regular voltage test leads should not be connected to or
disconnected from live circuits and should definitely not be
connected to or disconnected from voltages above 120 Vrms.
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 1000 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 III for a working voltage of 1000V, the
rating of the PS4550.

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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 2-
3%. 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.

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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 2.25%
accuracy and power and cost to a nominal 3% accuracy using the
HA5 probe.
The HA100 probe 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.

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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 clamp
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 (VN, V1, V2, or
V3) and each jack is similarly labeled (VN, V1, V2, or V3).
Note: The VN test lead is a different color from the other
leads (black). Similarly, the VN jack on PowerSight is a
different color from the other ones (black). Connecting
anything other than neutral or ground to the VN jack can
jeopardize your safety, the functioning of the unit, and the
accuracy of the unit.

13
Current probes plug into the top end of PowerSight, just above the
voltage inputs. Each current probe is labeled (I1, I2, I3, or IN) and
each jack is similarly labeled (I1, I2, I3, or IN). When plugging a
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
I1, 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.

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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 single-
phase and split-phase
service as found in a
residential service. In
North America, V1N
and V2N are 120V
and are 180 degrees
out of phase with
each other. When
heavier loads are
encountered, V12
(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 2, 3, 4, and 5 for
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 figure 6 for how 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

15
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 V1N
V1N = 277V for a 480V service) and all other measurements will
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. V2N and
V3N supply conventional 120V single-phase power and V1N
provides 208V, if needed. In this configuration, depending on
what you are measuring, you may choose to measure in phase-to-
phase 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.

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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 VN
voltage lead.
Similarly connect
the V1 lead to "Hot".
Since voltage now comes into PowerSight on V1 and current is
sensed by I1, the power and power factor for this single-phase
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 VN. 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

17
connections to PowerSight are as shown in figure 2, V1N will be
some relatively large number like 120 volts and V3N will be a small
voltage like 3 volts. If you then reverse the ground and neutral
leads, V1N will now read slightly less, like 117 volts. If "hot" and
"neutral" are reversed, then V3N 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)
offers 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.

18
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 the same
line voltage,
connect V1, V2,
and V3 to the
same "hot"
wire. I1, I2, and
I3 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.

19
In this configuration, the voltage, current, and power of each load
can be displayed directly or graphed on your PC using our PSM-A
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 VN
voltage lead
since it may affect the power factor readings of each phase.
In this configuration, a reading of V1N is of hot-neutral and V2N is
hot2-neutral. IN 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

20
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
warnings 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 system, 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.