Transcript basics_of_branch_cir..

Branch Circuit Testing
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
1 of 56
Branch Circuit Testing
• Why test branch
circuits
• Causes of branch
circuit failures
• Emerging
Technologies
• General Tests
methods
• Type of Testers.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
2 of 56
Why Test Branch Circuits?
Safety Issues
• Electrocution
• Equipment failure
• Fire caused by
Electrical circuits
– Branch Circuits with
or without AFCI
protection
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
3 of 56
Electrical Shock
Every week someone is killed by Electrocution through
installed home wiring.
• 490 people lost their life from
Electrocution in 1997* from:
– Consumer products – 24%
– Large appliances - 16%
– Installed home wiring - 12%
*NFPA and US Consumer Product Safety Commission 1997 data
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
4 of 56
Causes of Electrical Shock
Defective protection devices like TVSS, and GFCI
• There have been several changes to UL943
Requirement for GFCI’s due to studies over
several years of older units not operating properly.
• Effective January 2003
• www.ul.com/media/newsrel/nr072302
– Defective wiring, Neutral to Ground bonds.
– Poor Ground conductor circuit
– Poor Earth Ground
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
5 of 56
Equipment Failures
Failures result in:
•
•
•
•
•
Erratic operation
Lost productivity
Lost/corrupt data
Damaged equipment
Poor power efficiency
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
6 of 56
Fires
NFPA and US Consumer Product Safety
Commission 1997 data showed
– 406,000 residential structural fires
• Residential fires accounted for 74% of all
structure fires
– 3,390 civilian deaths and 17,775 injuries
• Residential fires resulted in 97% of all deaths
and 87% of injuries
– 9% of all structural fires and 7% of deaths were a
result of failures within the electrical distribution
system
www.cpsc.gov/library/fire97.pdf
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
7 of 56
Estimated Fire losses
Electrical
Distribution
Fires
Injuries
Deaths
Installed Wiring 14,600
420
110
Cord, Plug
6,300
320
90
Switch, Outlet
4,900
160
10
Lamp, light Fix. 9,900
350
30
Other
4,600
10
10
Total
40,300
1360
250
*NFPA and US Consumer Product Safety Commission 1997 data
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
8 of 56
Estimated Fire losses
• According to a recent report by the National
Association of State Fire Marshals, during the
period from 1994-1998, there was an average
of over 70,000 total electrical fires, which
were responsible for over 500 deaths
• Of these 70,000 electrical fires, 60,000 were
caused by arcing, not from an overloaded or
short circuit
"AFCI Inquiry and Report" by the Consumer Product Safety Task Force of the
National Association of State Fire Marshals, August 1, 2002.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
9 of 56
Causes of Electrical Fires
• Series Arcing Faults: can be Defined as a
partial or total conductor or path in series with the load
that alternates between infinite resistance to high
resistance or normal.
– Since the arc condition is in series with the load, the arc current
cannot exceed the loads current.
– Series arcs may contribute to insulation degradation that might
lead to parallel arc conditions.
• Example would be a break in the conductor which has carbonized
or has intermittent contact.
Arc-fault Circuit Interrupters--A Critical NEC 2005 Issue / High Resistance Series Fault 4
Brendan Foley, Joseph Engel, and Clive Kimblin.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
10 of 56
Causes of Electrical Fires
• Parallel Arcing Faults, occur as a short
circuit or a ground fault.
– A short circuit arc decreases the dielectric strength of insulation
separating the conductors, allowing a high-impedance, lowcurrent arc fault to develop, that carbonizes the conductor's
insulation, further decreasing the dielectric of the insulation
separating the conductors.
– The result is increased current, exponentially increased thermal
energy, and the likelihood of a fire. The current flow in a short
circuit, parallel arc fault is limited by the system impedance and
the impedance of the arc fault itself. Not necessarily the
breakers rating.
The Basics of Arc-Fault Protection
by Mike Holt, Mike Holt Enterprises, Inc. | Apr 01 '02 EC&M
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
11 of 56
Causes of Electrical Fires
• High Resistance Fault:
is a series fault characterized
by the presence of abnormally high resistance, compared to a
normal wire, wire termination, or wire splice, resulting in a
reduction of capacity and heat dissipation at the fault.
– These high resistance series faults result from a build-up of copper or
aluminum oxide that creates a high resistance, "glowing contact.“
– This high-resistance point can become extremely hot with temperatures
exceeding 600° F causing insulation failure, that can result in a
damaging high-power parallel arcing fault or ground fault.
– Glowing contacts can develop at virtually any electrical connection
conducting current. The current in the high resistance fault, like the
series arcing fault, is limited to the current being drawn by the load—
until the insulation degrades to the point where this type of fault
becomes a parallel arcing fault or causes leakage current to ground.
Arc-fault Circuit Interrupters--A Critical NEC 2005 Issue / High Resistance Series Fault 4
Brendan Foley, Joseph Engel, and Clive Kimblin.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
12 of 56
Causes of Electrical Fires
• Summary, Series or High Resistance Arc Faults:
are the results of defects in the wiring as part of a conductor or
connection that is in series with the load Since the arc condition is
in series with the load the arc current cannot exceed the Loads
current.
– Glowing contacts in copper or aluminum wiring
– High resistance in Back-wired devices like
receptacles
– Loose or corroded connections
– Bad splices
– Hot plugs, or high resistance contact between outlet
to plug.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
13 of 56
New Technology
• AFCI breakers were adopted in
the NEC 210.12 defined as a
device to provide protection from
an ARCing Fault.
• UL 1699 Defines the
requirements for these devices,
but the most common and
commercially available is the
Branch/Feeder or B/F type.
– In there are discussion that for
2008 a combination AFCI
breaker will be adopted. This
breaker would sense both Series
and Parallel faults.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
14 of 56
New Technology
• AFCI B/F breakers sense
common load current and adds
protections from parallel arcing
faults and Ground faults
• UL and EIA determined that
protection from a Series arc that
included arcing to ground be at
least 5 amps
• They also reported that the
lowest short circuit current lineneutral in the US to bewithin 75
amps at a receptacle.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
All currently available AFCIs
will detect line-to-ground arcs
at 50mA or above
15 of 56
New Technology
UL 1699 defined six devices, but three major types of AFCI's for branch
circuits, Branch/Feeder, Outlet Circuit, and Combination devices. The
Branch/Feeder type is the most common and the only device at this time
that satisfies the current NEC requirements.
• What does a Branch/Feeder AFCI do.
– Over current protection: This is the normal function of a breaker. To trip
when the load current has exceed the current rating of the breaker.
– Hazardous Arcing: An AFCI will trip when it senses a characteristic
arcing between line and neutral above 75 amperes.
– Ground Faults: The standard requirement for an AFCI is to trip on a line
to ground fault of 5 amperes or greater. Most AFCI will trip between
30mA to 50mA.
– Neutral to Ground Faults: If the neutral conductor comes in contact with
a grounded circuit the AFCI will trip.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
16 of 56
New Technology
Table of ARC Detection and Protection
Capability From A Branch Feeder AFCI
Arc Condition
Branch/Feeder type
Line-to-Neutral
Yes- 75 A
Line-ground
Series with ground
Series without gnd
Yes- 50 mA
Yes - 5 A
no
* Part of Table 1 from The Truth About AFCIs (Part 1)
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
17 of 56
Testing of the Branch Circuit
• General Testers cannot identify
High Resistance or Series faults
nor can they identify a Neutral to
ground bond
– Glowing contacts in copper or
aluminum wiring
– High resistance in Back-wired
devices like receptacle
– Loose or corroded connections
– Bad splices
– Hot plugs, or high resistance
contact between outlet to plug.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
A high resistance connection,
can result in hot spots or
Glowing connections which
can breakdown in insulation
and poor efficiency of the
electrical system
18 of 56
Testing of the Branch Circuit
• Nor can a General Tester identify a “False” or
“bootleg” ground
– Defined as an accidental short or improper bonding
of ground to neutral conductors
– Shows up as normally wired condition with general
receptacle testers
– Sensed by the new AFCI breakers, Conditions will
trip an AFCI at turn on.
• At times may be very difficult to locate.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
19 of 56
Testing of the Branch Circuit
• Before the adoption of the AFCI Circuit breaker, Many
of the same wiring faults existed and still exist today in
standard branch circuits,
– BUT DO WE TEST FOR THEM ON NON-AFCI CIRCUITS?
• AFCI’s have helped minimize wiring or load defects in
the branch circuits with which they are associated, but
it doesn’t address all circuits.
• Series faults are not covered by the present AFCI
technology.
• Is there a way to Identify many of the problems found
in branch circuits today?
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
20 of 56
Testing of the Branch Circuit
Using Voltage Drop
NEC code Articles {210-19(a) FPN No. 4} {215-2(d)
FPN No. 2} - “Branch circuit conductors should be
sized so as not to exceed a maximum voltage drop of
3% at the farthest outlet , and that the combined
voltage drop for both a branch and feeder should not
exceed 5%”
•
•
Measure the voltage drop at the furthest receptacle from the panel
Low voltage drop indicates a low impedance system
– Lowers the risk of hidden hazards
– Improves power efficiency and operation
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
21 of 56
Testing of the Branch Circuit
Testing under a load and calculating voltage drop
can identify common wiring problems
– Undersized wiring for load or length of run
• NEC 210-19(a) FPN no.4 states that conductors be sized to
provide reasonable efficiency of equipment operation
– High resistance connections
• Loose or corroded connections
• Poor splices
• Defective devices
• Voltage drop can detect an estimated 90% of defects on a
branch circuit
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
22 of 56
Testing of the Branch Circuit
• Lets do a little Experiment to
test this out. I have a circuit
with a receptacle at the end of
60 feet of wire
– With no-load is the voltage
the same on DMM A and
DMM B?
– Note reading
– With a load attached to the
circuit is the Voltage the
same on DMM A and
DMM B ?
– Note reading
• Calculate Voltage drop
© 2007 Ideal Industries
www.idealindustries.com
Voltage Drop = V (no-load) – V (load)
% Voltage Drop = Voltage Drop/ V (no-load)
Basics of Branch Circuit Testing
23 of 56
Testing of the Branch Circuit
We all remember the Old Way
• A hair-dryer or drill worked
well as a load for this test
• We Measured the line
voltage with no-load and
then with load and recorded
the reading
• If a circuit was already
under a load the additional
10-12 amp load would trip
the breaker
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
24 of 56
Testing of the Branch Circuit
Using Modern Technology
• A Device like the IDEAL
SureTest circuit analyzer
places a load on the line and
Calculates the 12, 15, and 20
ampere voltage drop.
– One method to Identifying
High resistance circuit faults
• Patented technology pulses the
load on the line without
tripping circuit breakers or
interrupting existing
equipment
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
25 of 56
Testing of the Branch Circuit
Calculating Voltage Drop
• VD = I x R
– I = Current = 16 Amperes
– R = Resistance of conductors = .4 Ohms
• 2 Ohms/1000 feet for 12 gauge (Chapter 9, Table 8)
• 2 Conductors of 100 ft = 200 Feet
• (2/1000) x 200 = 0.4 Ohms
• VD = 16 A x 0.4 = 6.4 Volts
• VD% = 6.4/120 = .05333 or 5.3
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
26 of 56
Testing of the Branch Circuit
• Using this method not
only helps us determine
the integrity of the
circuit, it also gives
additional information,
not just the resistance of
the conductors, but of
the entire circuit.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
27 of 56
Testing of the Branch Circuit
Finding the Cause of High Impedance
• Measure the voltage drop at the furthest receptacle from
the panel and record the reading
• Repeat this at each receptacle until you find a significant
decrease in voltage drop from one receptacle to the next
– At that point check the circuit and wiring leading to the last
receptacle.
• Check voltage drop on remaining receptacles
– If voltage drop is acceptable in remaining receptacles, then the
problem is probably localized at the receptacle connection
– If voltage drop is unacceptable, then the problem exists within
the hot or neutral conductors
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
28 of 56
Testing of the Branch Circuit
Finding the Cause of High Impedance
If all devices have high voltage drop then
the high impedance is caused by:
– Undersized wire for length of run
– Splice between the panel and the first device
– Poor connections or corroded contacts at
panel, breaker, neutral bus, etc.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
29 of 56
Testing of the Branch Circuit
Finding the Cause of High Impedance
In this example there is a poor connection between Device
2 and 3 which did not show up with a DMM reading.
Under a load test the voltage drop on device 3 and 4 was
12%. The voltage drop at device 2 decreased to 8%.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
30 of 56
Testing of the Branch Circuit
• SureTest also shows
correct wiring including
Identifying Neutral to
ground contact faults to
within 15’ of the fault and
15’ from the panel.
• Conductor impedance of
Hot, Neutral and ground
• N-G Voltage
• GFCI With time to trip
• ARCI Fault testing
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
31 of 56
Testing of the Branch Circuit
Finding Hot Spots
• Most poor panel connections show
up as hot spots in the panel
– Test quickly with an infrared
temperature meter
• Voltage drop across contact point,
such as a breaker should not
exceed 10mV to 100mV. This is
also true for switch contacts.
– Check contact points and breaker
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
32 of 56
Testing of the Branch Circuit
Importance of the Ground wire
Three major reasons for ground
• To provide Zero reference for the electrical
service
• Provide a low resistance path to protect from
electrical faults
• Protect equipment against static electricity and
protect against frame potential for the
operator’s safety
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
33 of 56
Testing of the Branch Circuit
Common Faults with the Ground wire
• High impedance grounds
– Rule of thumb < 1 Ohm
– Electronic equipment and data networks require very low
impedance
• IEEE recommends < 0.25 Ohms
• False Grounds
• Undersized ground conductor, corroded or loose contacts
– If circuit conductors are increased in size to accommodate
voltage drop the ground should also be sized accordingly (NEC
–122(b)
The SureTest Patient Technology can test the Impedance The
ground wire and also Identify false or N-G faults
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
34 of 56
Installation of Safety Devices
• Ground Fault Circuit
Interrupters
– NEC requires installation of
GFCI in bathroom, kitchens
and outside.
– Purpose is to protect
individuals by detecting
ground faults.
– Defective or improperly
installed GFCI can lead to
shock.
© 2007 Ideal Industries
www.idealindustries.com
SureTest family have GFCI testing,
some provide in the test
Current and time to trip information
Basics of Branch Circuit Testing
35 of 56
Ground Electrode
• NEC Code 250-56 requires a
single ground electrode to have
25 Ohms or less resistance, and if
not, be augmented by one
additional rod spaced at least 6’
apart of any type specified in
section 250-50 or 250-52
• This measurement can be taken
with a three point earth resistance
tester or a ground resistance
clamp meter
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
36 of 56
Integrity of the Branch
Circuit
Causes of AFCI Tripping at turn on
• Over-current. For any current above its current rating it will trip
according to its circuit breaker time-current characteristic.
• Hazardous arcing. For arcing at current levels of about 75
amperes and above, the AFCI will trip. Commercially available
AFCIs will actually operate at some level below 75 amperes. The
AFCI will operate faster than a fuse or circuit breaker under shortcircuit over-current conditions up to about 125 amperes.
• Arcing ground faults. The standard requires tripping on faults of
5 amperes and greater. Commercial units will actually detect
ground faults of 50 milli-amperes and greater. Tripping will be
instantaneous, with no intentional delay.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
37 of 56
Integrity of the Branch
Circuit
Shared Neutral in residential wiring t
Shared Neutrals is a practice
where one three wire
conductor is used as a
homerun for two singlephase circuits.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
38 of 56
Integrity of the Branch
Circuit
Causes of Tripping at breaker turn on or with load
• Neutral grounding. If the neutral conductor (grounded-circuit
conductor) of an AFCI protected circuit touches the ground wire
or grounded metal, the AFCI will trip, if the impedance to ground
is very low impedance.
• Abnormal environments. Some abnormal events may also cause
tripping, such as high voltage surges from lightning or utility line
surges, voltage or frequency fluctuations from poorly regulated
backup generators, or mechanical shock.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
39 of 56
Integrity of the Branch
Circuit
Finding the Causes for the Trip
• If after Energized, an AFCI circuit immediately trips,
what steps should be taken?
• Well , a lot of approaches have been suggested , but an
orderly search or approach will help reduce the stress.
• Remember that AFCI’s have two primary Functions
– Over-Current sensing
– Arc Fault condition
• One of the most common faults is found to be a *
Neutral to ground contact fault or false ground.
* The SureTest Patient Technology can test the Impedance
of the ground wire and also Identify false or N-G faults
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
40 of 56
Integrity of the Branch
Circuit
Finding the Causes for the Trip
• The AFCI will sense an arc that occurs because of Insulation
or isolation break-down, which can be tested with an
insulation tester
– Disconnect all loads and verify that unconnected wire
ends are insulated.
– Disconnect the load wire to the AFCI, or GFCI in the
circuit. Use the Megger to apply a direct voltage starting
with 250 then 500.
• It is always best to start with a voltage that is 2X the rating
of the source and increase if necessary
• A rule of thumb is, roughly 1 megohms per 1000V, but it is
always best to consult with the wire manufacturers for best
results.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
41 of 56
Integrity of the Branch
Circuit
Finding the Causes for the Trip
• If the trip is not Instantaneous, it would indicate an
overload trip
• Energize the circuit and measure the load current
over time. A clamp meter should be able to
determine this.
– A DMM with CT that has a fast Peak hold function, may also be useful in
Identifying between Over-Current and Arcing.
– Disconnect load and reinstall to Identify the defective device.
Finding the Causes for the Trip
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
42 of 56
Integrity of the Branch
Circuit
Finding the Causes for the Trip
• If the trip is Instantaneous, it could indicate
Ground Faults or earth leakage.
• Ground faults are small amounts of current that
“leak” over to ground caused by deteriorating
insulation or moisture.
– A Low amperage current clamp or clamp meter, with a low
range having the ability to measure 5-10 mA accurately, could
help.
• The GFCI or AFIC measure the difference between current
out and current in. If there is an imbalance, it will trip.
• Disconnect load and reinstall to Identify the defective device.
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
43 of 56
Branch Circuit Testing
Protect personnel and equipment by:
• Verify that electrical devices have been
wired up correctly
• Maintain a low impedance electrical
system
• Maintain a good electrical ground
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
44 of 56
Branch Circuit Testing
Use certified devices and testing equipment
• Not all Testers are what they seem to be!
• Branch circuit testing should
– Verify proper wiring
– Measure the integrity of the branch circuit
– Measure the integrity of the ground conductor
• Measure the integrity of the ground
electrode
• Install and test the operation of safety
devices
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
45 of 56
Branch Circuit Testing
• Certification labs test devices
and equipment for failure
under extreme conditions to
protect consumers
• With “Free trade and open
markets” there has been an
surge of counterfeited
certifications
• UL provides information on
their web site
© 2007 Ideal Industries
www.idealindustries.com
www.ul.com/retail/certified.html
Basics of Branch Circuit Testing
46 of 56
Receptacle Testers
• Check to ensure that
devices have been wired
up correctly immediately
after installation
–
–
–
–
Proper wiring of receptacle
Correct voltage level
Good continuity on switches
Warn against faulty wiring
in 3-wire receptacles
• Test GFCI receptacles for
proper operation
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
47 of 56
Branch Circuit Testing
• To test a GFCI, an imbalance
needs to be placed between
hot and neutral
• The the amount of imbalance
and time to trip should be
monitored to verify GFCI
performance
• Many receptacle testers will
test GFCI receptacles
• The Ideal 61-058 will not
only test GFCI but will also
test the AFCI Breaker
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
48 of 56
Circuit Identifiers
• Identify circuit
breakers and fuses
without service
interruption
• Automatic or
adjustable sensitivity
levels
• Visual and audible
indication
© 2007 Ideal Industries
www.idealindustries.com
61-532 model has an Analog Receiver
61-534 has Digital Receiver w/ NCV, High
voltage transmitter with GFCI
Basics of Branch Circuit Testing
49 of 56
Voltage/Continuity Testers
• Test from ranges of 6600V volts AC or DC
• Some units vibrate to
provide tactile
indication of voltage
level
• Audible continuity
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
50 of 56
Branch Circuit Testing
• To test a AFCI you need to
generate a number of high
current pulses to simulate
the effect of an arc
condition that may exist in
wiring or cords,
• IDEAL has Two Testers
which can simulate an arc
• They Are the;
– 61-058 GFCI/AFCI testers
– 61-165 Circuit Analyzer with
AFCI and GFCI
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
51 of 56
SureTest Circuit Analyzer
• Measures integrity of a branch
circuit
– Voltage drop under an actual
12, 15, 20 Amp load
• Measures Conductor and ground
impedance
• Wiring and Identifies false
grounds
• GFCI
• AFCI
• Some models not shown Measure
harmonic distortion
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
61-164
SureTest
Circuit
Analyzer
61-165
SureTest
Circuit
Analyzer with
AFCI
52 of 56
Infrared Temperature Meter
• Checks for hot spots in breakers and panels
• Laser point sighting to target device under
test
• 15 to 1 angle of view ability
– 15 inches from panel will measure temperature
across 1 inch circle
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
53 of 56
Earth Testers
• Ideal/Megger 61-788
– 3 pole Testers
• IDEAL/Megger 61-789
– 4 pole Testers
– Self powered - no need for
hand crank
– Low power consumption
Compact and lightweight
– Quick battery check
– Limited lifetime warranty
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
54 of 56
Earth Testers
• Ideal 61-920 Ground
Resistance Clamp
–
–
–
–
–
–
Ground Resistance
Ground Leakage Current
Auto ranging
Audible indication < 40 ohms
Open jaw indication
Data hold
© 2007 Ideal Industries
www.idealindustries.com
Basics of Branch Circuit Testing
55 of 56