Variable frequency drive (VFD) systems can cause costly downtime if they or their connecting cables fail. While VFD electronics have become reliable, cables are more vulnerable because they lack protections from voltage spikes and other power issues. Selecting cables designed for VFD applications, with materials like semiconductive insulation that reduce voltage stress, optimized stranding to lower resistance, and shielding against electrical noise, can help avoid cable failures and improve overall drive system performance and reliability.
The outdoor silicone-rubber insulation design includes a skirt configuration that offers exceptional creep, strike, weather and contamination resistance, along with superior cable sealing and voltage withstand. All termination kits come complete with the housing and stress tube pre-assembled on the core, ready for quick and easy installation.
“The Ranger2® Shrink-Fit Terminations enhance the breadth of our Elastimold® line of pre-molded cable accessory components,” said Mike Jackson, Product Manager for Thomas & Betts. “Their design provides the superior skirt configurations for riser pole, pad-mounted and other installations exposed to the elements.”
The single-piece terminations for 15kV and 25kV applications feature shrink-fit design for effortless installation. The two-piece termination for 35kV applications facilitates easier core removal: one needs only to position the terminator on the prepared cable and remove the center core. The terminations are compact and lightweight to enable installations in restricted spaces and free-hanging applications.
Elastimold® Ranger2® Shrink-Fit Terminations 15-35kV meet or exceed all requirements of IEEE Standard 48 for Class 1 outdoor or Class 2 indoor terminations.
Surge Protect, a critical issue you could not fail to know while implementing...Victor Lee
How high should we aim? Sparkovers (flashovers) which occur almost naturally in building wiring systems protect most equipment locations for surges above 6kV. So 6kV is the upper limit we should be concerned about. Note that poor or mediocre wiring insulation materials ironically help protect equipment better than excellent and expensive insulator materials.
There is increasing talk about “6kV surge protection”. We now realize why 6kV is being picked. However, we should keep in mind that so far such requirements are voluntary. But even if they do become mandatory, note that there are already designated “levels” of surge withstand capability: 2.5kV, 4kV, and 6kV, similar to CISPR 24. So it is probable that much like with CISPR 24/EN55024 we may only need to comply with a level lesser than max.
Composite inter phase separators have a great role to play to compact the lines and avoid flash-overs & short circuits resulting from conductor swing and galloping.
Thorne & Derrick UK are official distributors of the SebaKMT range of LV-HV Cable Fault Location instruments including cable sheath testers and cable sheath fault prelocation and pinpointing units. SebaKMT are the leading manufacturer of measurement equipment for the diagnosis of cable networks and for cable fault location. Cable faults are the ''natural enemy'' of reliability. The innovative SebaKMT products make it possible to quickly localise low and high voltage cable faults without causing damage to fault-free parts of the cable.
SEBA KMT MFM5-1 is the universal test instrument for cable sheath testing including prelocation and pinpointing of cable sheath faults - in sheath testing mode SEBA KMT MFM5-1 can detect minute cable sheath insulation damage on low and high voltage cable networks.
SEBA KMT MFM5-1 ensures fast and precise cable sheath fault location - the instrument is menu-driven and fully automatic sheath fault prelocation is accurately achieved by inputting total cable length. SEBA KMT ESG 80-2 can be combined with the MFM5-1 for earth fault location in LV-HV cables.
Cable Sheath Test & Fault Location SEBA KMT MFM5-1 Features : Sheath testing, fault prelocation and pinpointing combined in single unit, sheath testing up to 5kV, time saving prelocation of sheath fault.
The outdoor silicone-rubber insulation design includes a skirt configuration that offers exceptional creep, strike, weather and contamination resistance, along with superior cable sealing and voltage withstand. All termination kits come complete with the housing and stress tube pre-assembled on the core, ready for quick and easy installation.
“The Ranger2® Shrink-Fit Terminations enhance the breadth of our Elastimold® line of pre-molded cable accessory components,” said Mike Jackson, Product Manager for Thomas & Betts. “Their design provides the superior skirt configurations for riser pole, pad-mounted and other installations exposed to the elements.”
The single-piece terminations for 15kV and 25kV applications feature shrink-fit design for effortless installation. The two-piece termination for 35kV applications facilitates easier core removal: one needs only to position the terminator on the prepared cable and remove the center core. The terminations are compact and lightweight to enable installations in restricted spaces and free-hanging applications.
Elastimold® Ranger2® Shrink-Fit Terminations 15-35kV meet or exceed all requirements of IEEE Standard 48 for Class 1 outdoor or Class 2 indoor terminations.
Surge Protect, a critical issue you could not fail to know while implementing...Victor Lee
How high should we aim? Sparkovers (flashovers) which occur almost naturally in building wiring systems protect most equipment locations for surges above 6kV. So 6kV is the upper limit we should be concerned about. Note that poor or mediocre wiring insulation materials ironically help protect equipment better than excellent and expensive insulator materials.
There is increasing talk about “6kV surge protection”. We now realize why 6kV is being picked. However, we should keep in mind that so far such requirements are voluntary. But even if they do become mandatory, note that there are already designated “levels” of surge withstand capability: 2.5kV, 4kV, and 6kV, similar to CISPR 24. So it is probable that much like with CISPR 24/EN55024 we may only need to comply with a level lesser than max.
Composite inter phase separators have a great role to play to compact the lines and avoid flash-overs & short circuits resulting from conductor swing and galloping.
Thorne & Derrick UK are official distributors of the SebaKMT range of LV-HV Cable Fault Location instruments including cable sheath testers and cable sheath fault prelocation and pinpointing units. SebaKMT are the leading manufacturer of measurement equipment for the diagnosis of cable networks and for cable fault location. Cable faults are the ''natural enemy'' of reliability. The innovative SebaKMT products make it possible to quickly localise low and high voltage cable faults without causing damage to fault-free parts of the cable.
SEBA KMT MFM5-1 is the universal test instrument for cable sheath testing including prelocation and pinpointing of cable sheath faults - in sheath testing mode SEBA KMT MFM5-1 can detect minute cable sheath insulation damage on low and high voltage cable networks.
SEBA KMT MFM5-1 ensures fast and precise cable sheath fault location - the instrument is menu-driven and fully automatic sheath fault prelocation is accurately achieved by inputting total cable length. SEBA KMT ESG 80-2 can be combined with the MFM5-1 for earth fault location in LV-HV cables.
Cable Sheath Test & Fault Location SEBA KMT MFM5-1 Features : Sheath testing, fault prelocation and pinpointing combined in single unit, sheath testing up to 5kV, time saving prelocation of sheath fault.
Neurocampus punto de partida para la transformación académicaDaniela Pérez Michel
Presentación sobre el Proyecto Neurocampus del INNN, donde se habla de las fortalezas y dificultades encontradas para su implementación así como el plan de capitalización para el futuro
Sheikh Naveed is Karachi based graphics & web designer, blog editor, in field of logo design, web design, photo editing and enhancement etc.
Join me on Facebook, twitter or flickr.
Instrumentation Cable In India are a couple of conductor cables that carry low strength electric indicators used for tracking or controlling electric strength structures and their related approaches.
Prysmian offers a comprehensive range of flexible cable solutions with Class 5 conductors for fixed installations. With Flexible XLPE and Fire Performance cables, Prysmian has a full suite of cables for the entire Construction market.
In order to deliver the energy required to light high intensity lights, lamps, and beacons, a careful selection of wire and cable is required The electrical wire delivering the charge to this system and its connection to the lamp play a vital role and work in harmony with each other to ensure circuit integrity and lights always illuminated. Many electrical wire and cable considerations include: Voltage rating, temperature rating, shielding, oil and moisture resistance, Standards Agency Requirements, armor requirements, routing considerations, UV resistance etc. lengths of cable, cable weight and finished diameter, voltage drop, etc.
Sound cable design considerations, and the
use of high quality state of the art
insulating materials, coupled with solid
American Craftsmanship greatly positively
influence the cables performance.
Thermal Wire has had great success with
the following 3 cable types:
Hybrid
Retractable systems
Stationary Shielded Power and Control Cables
Purchase your Cable Jointing Kits from Compaq International (P) Limitedcompaqinternational
Compaq has been in existence since 1997.It is concerned with producing a range of cable accessories that are capable of handling overvoltage, strikes and power surges.
Principals of Low Resistance Testing Webinar with MeggerTranscat
During this webinar you will learn the following:
• What is considered a Low Resistance Test?
• When to measure Low Resistance
• Why measure Low Resistance?
• Benefits of Low Resistance Testing
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GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
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1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
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- Reduction in onboarding time from 5 weeks to 1 day
- Improved developer experience and productivity through actionable findings and reduction of false positives
- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
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Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
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Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
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Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
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Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
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Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf
Seleccion de cables para vfd
1. For all their energy savings and process control benefits,
variable frequency drive (VFD) systems have a downside too.
When these drives fail, they can bring motor-driven industrial
processes to a dead stop. To avoid this costly downtime, smart
engineers carefully evaluate reliability when configuring a drive
system.
All too often, however, the reliability analysis focuses solely on
the VFD power electronics and neglects the most vulnerable
component in the drive system–the power cable that connects
the VFD to the motor.
The truth is, however, that power electronics have already
become very reliable over the years. By design, they can handle
the typical voltage spikes, inrush currents, harmonics and other
power distortions that arise during VFD operation. Their controls
can also prevent damaging electrical conditions or shut down
the drive altogether if power distortions rise to unsafe levels.
Cables do not have any such protection and can fail if subjected
to electrical conditions that generate more heat or voltage
levels than the cable’s insulating layers can tolerate. Cables in
industrial settings may also experience mechanical loads and
chemical exposures that lead to damage and premature failure.
Fortunately, it is possible to avoid VFD-related cable failures
and the associated downtime by paying attention to a few cable
construction details. The overall performance of the drive system
will also improve in many cases. Here’s what to look for:
The Right Materials
Not all insulation and jacketing materials are created equal when
it comes to electrical performance. So it’s important to match
cable materials to specific VFD application requirements.
Even medium power VFD applications, for example, run the risk
of damage from voltage spikes or other power distortions (See
“The Problem With Cables” sidebar). In these cases, consider
VFD cables that make use of semiconductive layers between
the conductors and the primary insulation. Semiconductive
insulation systems have for decades been employed in the high
voltage cables used for power distribution. More recently, they
have been applied to VFD cables to protect against electrical
damage.
Semiconductive insulation works by alleviating corona discharge
and high points of electrical stress in primary insulation. The
result is greatly improved cable reliability, extended life and
an increase in dielectric strength properties. Our testing under
the ICEA T-24-380 standard shows that when compared to
other insulative systems corona inception and extinction levels
improved significantly when semi conductive compounds were
used.
Another VFD application challenge involves long cable runs,
which are increasingly common in modern manufacturing
facilities. Because capacitance loads increase with length, these
long cable runs have an increased risk of overload conditions
that can trigger the VFD’s protective systems.
Selecting Cables
For VFD Applications
Review four cable design factors to maximize reliability in drive applications
Lapp Group 29 Hanover Road, Florham Park, NJ 07932 T. 800 774 3539 www.lappusa.com
www.lappcanada.com
By John Gavilanes, Director of Engineering
2. LAPP VFD ADVANTAGES
Products
ÖLFLEX®
VFD
XL
ÖLFLEX®
VFD
Slim
VFD Generic
Type B
.045 XLPE Surge Guard .045 XLPE
Jackets
Specially
formulated PVC
Specially
formulated PVC
PVC
Properties Ratings Comments
DC Resistance (ohms/1000 ft.) 1 1 2 #1 - Stranding meets UL & VDE
Voltage Drop (volts) 1 1 2 #1 - Lowest voltage drop
Longer Lengths (feet) 1 1 2 #1 - Longest lengths
Ampacity (amperes) 1 1 2 #1 - Highest ampacity
Corona Testing (voltage) 2 1 2 #1 - Highest inception/extinction
Capacitance (conductor – conductor) 1 2 1 #1 - Lowest capacitance
Impedance (ohms) 1 2 1 #1 - Higher impedance
Inductance (henrys) 1 2 1 #1 - Higher impedance
Oil (aging) 1 1 3 #1 - Meets Oil Res II
Low Temperature (degrees Celsius) 1 1 3 #1 - Meets -25°C cold impact
Flexibility (durometer) 1 1 3 #1 - Highly flexible
Mechanical (pound-force) 1 1 3 #1 - Crush/impact force
Shield Effectiveness (decibels) 1 1 2 AMA tape vs. AM tape
1 = Best 2 = Average 3 = Fair
The use of cables with the crosslinked polyethylene (XLPE)
insulation can minimize this risk.
XLPE insulation has a relatively lower dielectric constant that
reduces the capacitive effect in long cable runs. XLPE also has
excellent thermo-mechanical properties that allow the XLPE
insulation to withstand the heat generated by overcurrent
conditions.
VFD applications requiring high precision control impose yet
other requirements on the cable. Though it may not be obvious,
the cable’s insulation can actually influence the control response
of the drive. An appropriate insulation system, will minimize
transfer impedance and improve the velocity of propagation to
produce a more efficient control response.
Mechanical Performance
With VFDs typically installed in factory environments, cables
must be engineered to withstand mechanical abuse and
environmental exposures. Some of the key mechanical attributes
in VFD installations include:
• Flexibility. Enhanced flexibility pays off throughout the cable’s
life cycle. During installation, flexibility makes handling and
routing easier. In use, flexible cables are less susceptible
to damage from bending. Stress free cables, created by
removing the back twist from cables, is one way to improve
flexibility and is an important feature to look for when in tight
bend radius installations.
• Oil Resistance. For industrial applications where oil exposure
is a concern, make sure that you select cables with a PVC
jacket that has been specially formulated for oil resistance.
Cables that comply with Underwriters Laboratories’ stringent
oil resistance standards can be surface marked as Oil
Resistant I or Oil Resistant II.
• Crush Tested. Consider whether cables have the crush
resistance needed for the installation. Cables certified as
TC-ER, for both tray and exposed run installation, have to
pass rigorous mechanical tests for cable crush and impact
resistance, including UL Standard 1569. Because these
rugged cables need no conduit, they can significantly drive
down installation time and cost.
Lapp Group 29 Hanover Road, Florham Park, NJ 07932 T. 800 774 3539 www.lappusa.com
www.lappcanada.com
3. Proper Shielding
Because VFDs can be susceptible to electrical noise, particularly
in process control applications, it’s important to pay attention
to the shielding methods used in both the cable itself and any
connectors.
The most effective type of shielding combines a triple-laminate
foil tape and 85% braid coverage. This eliminates two types
of noise problems: 1) it prevents externally generated noise
from entering and causing internal signal disruptions, 2) and it
also prevents noise generated from within the cable itself from
exiting, which could cause unintended disruption to nearby
electronic equipment.
As for the connectors, they need to be well shielded too. Look
for those which provide full shield grounding, low transfer
impedance from the shield to conduit entry plates, and 360° of
termination. Connectors with these features are referenced in
Section 4-5 of Rockwell Automation’s Wiring and Grounding
Guidelines for Pulse Width Modulated AC Drives.
Optimized Stranding
Cables stranding designs, which can vary substantially, also play
a role in the efficiency of a drive system. One often neglected
consideration involves the cable’s circular mil area, or CMA.
Cables whose conductors have a large CMA have lower DC
resistance than cables with a smaller CMA. Low DC resistance,
in turn, translates to significantly lower voltage drop across a
given length of wire.
Conclusion
With VFDs now firmly established in manufacturing settings, their
uptime matters more than ever. Engineers, however, often forget
to consider the contribution that power cables make to the
overall reliability and performance of the VFD system. Choosing
cables whose materials, mechanical performance, shielding and
stranding are designed for electrical and environmental stresses
of a VFD application is one of the simplest ways to keep that
drive up and running.
Lapp Group 29 Hanover Road, Florham Park, NJ 07932 T. 800 774 3539 www.lappusa.com
www.lappcanada.com
Voltage Drop Comparison
Cable Sample
AWG
Stranding
Circular Mil
Area
DCR
(ohms/1000 ft.)
Current
(amperes)
Calculation:
DCR x Current
Voltage Drop
(volts)
ÖLFLEX®
VFD XL
12;
Class 5
7665 1.36 5 1.36 x 5 = 6.8
VFD Generic Type B
12;
65/30
6500 1.72 5 1.75 x 5 = 8.6
Lapp’s ÖLFLEX®
VFD XL exhibits approximately 25% less DC resistance than the VFD generic type B product. This
substantial difference precipitates a significant decrease in voltage drop, a higher current carrying capability, and the
option of accommodating applications that require longer cable lengths. More copper means less resistance which
results in less heat generated.
4. LAPP GROUP PRODUCTS
Product Name Description UL / CSA Approvals
UL Oil
Res I
UL Oil
Res II
-25°C
Impact
-40°C
Bend
FT4
Flame
ÖLFLEX®
VFD XL Power Control Tray Cable
600V – TC
WTTC 1000V CIC/TC
X X X X X
ÖLFLEX®
VFD Slim Power VFD Cable
600V – TC
WTTC 1000V CIC/TC
X X X X X
ÖLFLEX®
VFD Symmetrical Power VFD Cable with Symmetrical Grounds
600V – TC
WTTC 1000V CIC/TC
X X X X X
ÖLFLEX®
VFD Power VFD Cable with Inner Jacket Bus Drop MTW 600V X X X X X
ÖLFLEX®
VFD with Brake Power VFD Cable with 1 Pair for Brake
600V – TC
WTTC 1000V CIC/TC
X X X X X
ÖLFLEX®
FD VFD Power VFD Cable for Continuous Flex
600V – TC
WTTC 1000V CIC/TC
X X X X X
ÖLFLEX®
SERVO 2YSLCY-JB Flexible European VFD Power Cable 1000V – CE X
To provide the most effectiveness, the use of Lapp SKINTOP® MS-SC/MS-SCL or MS-SC-M BRUSH/BRUSH PLUS is recommended to achieve full 360° shield ground termination.
Lapp Group 29 Hanover Road, Florham Park, NJ 07932 T. 800 774 3539 www.lappusa.com
www.lappcanada.com
In VFD operations, the inversion voltage normally rises from zero to
650 volts then back to zero approximately 20,000 times per second.
During these fluctuations, the nominal voltage can overshoot from
650 volts to 2,000 volts or more. Even though these voltage spikes
last for only millionths of a second, they can permanently damage
or even destroy an improperly designed cable.
Voltage spikes do their damage when they puncture the cable
insulation, which allows the current to travel into the braid shield.
The current can generates enough heat to burns a hole in the
braid. When the hole grows large enough, the cable insulation
will self-heal, leaving lasting damage to the braid. This process
will repeat at different locations along the length of the cable
until total failure has occurred, leading to production downtime.
It’s worth noting that longer lengths of power supply cable will
experience voltage spikes more frequently and more intensely
than shorter lengths.
The Problem With Cable