Jake Wattenphul

Harmonic Filters for Reducing VFD Distortion


VFDs create harmonic distortion. Any VFD using a bridge rectifier inherently draws harmonic current from the utility. The harmonic current draw causes voltage distortion on the mains which can create power quality issues for other electrical loads.


KEB Harmonic Filters are used to reduce VFD distortion and meet IEEE 519 distortion levels. Using a harmonic filter with a VFD reduces the amount of harmonic current, therefore, the voltage distortion on the mains is reduced.


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Electrical loads like resistors and line fed induction motors draw a sinusoidal current from the supply.


Most commercial VFDs use a 6-pulse bridge rectifier to convert from AC to DC power.  6-Pulse inverters draw a non-sinusoidal input current which then creates distortion on the supply voltage.


The voltage distortion is undesirable because it can negatively affect the operation of other electrical loads.


Critical applications using VFDs like wastewater treatment plants, elevators, and airports might need to mitigate harmonic distortion.  There are a number of ways to address harmonics, but harmonic filters strike a good balance between performance and cost.


KEB’s Z1 (zee-one) Harmonic Filters are designed to meet IEEE (eye-triple-E) 519 (five-nineteen) harmonic levels.  The filters are offered in graduated sizes up to 400Hp.


In order to achieve the best possible performance, KEB offers filters for different electrical mains around the globe.  Filters are available for both 230V and 480Vac mains.  Additionally, filters optimized for both 50Hz and 60Hz mains are offered.


KEB Filters are intended to be used for demanding industrial VFD applications and feature a 150% current overload rating for 60 seconds.


As standard, the units feature overload protection and temperature sensors for the filter windings.


The Z1 filters are 99% efficient at full load.  This is achieved through the use of high quality steel laminations and winding configuration.


KEB’s Z1 filters feature high-performance 3-phase capacitors for increased operating lifetime and reliability.


The harmonic filters use a compact design and flexible mounting concept.  The capacitor bank can be mounted separately from the core – up to 2 meters apart.  This allows a machine builder to flexibly position and mount the components inside an enclosure.


As an option, the large filters are offered in a pre-wired NEMA1 enclosure.


KEB Harmonic filters are UL listed and carry a CE mark to ensure the highest quality and performance.



High Speed Elevator in Long Island City NY | Machine Room Vids #06


In this episode we give an overview of a high speed elevator machine room in a rapidly changing area of NYC – Long Island City. Many dated industrial buildings are being replaced by high rise buildings.


We visit a machine room where KEB Elevator Drives are running 1000FPM cars and using regenerative drives.


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So Long Island City is just on the on the east side of the East River across from Manhattan. The area is booming with buildings so a lot of new high-rises are going up in the area. As you look around you can see a lot of tall buildings going in, residential towers replacing a lot of old industrial areas.


Hi I’m Tony Heiser with KEB America. Today I’m visiting One Queens Plaza South Tower in Long Island City in New York. This particular building has MCEI control KEB F5 elevator drives and R6 line regen units and imperial PM gearless AC machines. Cars here 1000FPM.


With space as a premium a lot of these industrial areas are being ripped down and high-rise buildings are going up to accommodate many times for rental units and housing units. Being that space is a premium you have to build higher and with the higher rises you need a faster elevators, higher speed elevators. Often in the 500FPM to 1200FPM range.


A lot of the buildings that we’re seeing in Long Island City is that are going up are the high-rise buildings and many of them are at the thousand foot per minute threshold.

Modbus VFDs


Communication protocol: Modbus for VFDs


KEB offers a full line of VFDs with Modbus RTU and Modbus TCP communication options.


KEB’s F5 product is scalable from 1Hp to 1000Hp. Units are offered in both 230V and 480V power classes. The drives support both open and closed-loop motor control. They can be used to drive servo motors and have an internal 32-bit positioning function for motion control applications.


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KEB’s F5 VFD platform offers solutions for both Modbus RTU and Modbus TCP/IP applications.


The Modbus communication is handled through a flexible operator which is available for all control card types.


The F5 is offered in different power gradients up to 1000 Horsepower.   Units are offered in dedicated 230V and 480VAC power classes.


The F5 is capable of running both induction motors and AC servo motors.  It supports a variety of different control platforms for open loop and closed loop applications.  The F5 even supports an internal 32-bit positioning module for motion control applications.


The F5 has a compact form factor and is available with an integrated braking transistor for regenerative applications.


Contact KEB to learn more about our Modbus automation products.


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DC to AC Elevator Modernization


The benefits of elevator modernization – updating a system to AC gearless using KEB drives and regen units – include power savings, lower noise levels, faster floor-to-floor times and less carbon dust floating around the motor room.


DC motors were great in their day, but newer AC gearless motors offer increased performance, better power savings and the ability to regenerate excess power to put back on the building’s power grid.


For more info on TEI Group, visit their web site


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As everybody knows we are all interested in the greening of our world environment and moving from DC to AC and using KEB regenerative drives affords an energy savings for the building as well as a smaller carbon footprint all around.


Ok so, my name is Wayne Locker, I’m an employee at TEI group. TEI group is a member of IUEC which is the International Union of Elevator Constructors. My key area of responsibility of TEI group is technical support for our maintenance department, modernization, and construction departments.


The elevators here are 600-foot-per-minute – both the high-rise and the low-rise, 24 landings total. We’ve modernized eleven cars. They were all previously a mixture of DC gearless and
DC geared machines. They’ve all been modernized to AC PM gearless and the couple of DC geared cars are AC gearless induction motors all driven by GALaxy controllers and a KEB 5 drive. We also use the KEB R6 regen units to help us do a little power savings instead of dumping into a resistor.


So some of the reasons to modernize from DC equipment to AC equipment for the building owner is ease of maintenance. No more commutators, no more carbon dust floating around the machine room getting into printed circuit boards. The DC equipment was driven by motor generator sets – which were great in their day, but also are very high maintenance. Create a tremendous amount of audible noise, electrically very inefficient. Even though they do regenerate, the amount of energy used to turn them sort of negates that slightly. They also produce a tremendous amount of heat so it takes more energy to cool down the machine room. They also generate more carbon dust which also finds its way into sensitive electronic equipment and into the air that we breathe as well. The new AC PM motors are more efficient. There’s a big energy savings involved.


There are some safety mechanisms involved when you do a modernization. You are bringing up your entire elevator system to code. Some of the newer gearless machines have the secondary emergency brake already fitted onto it. With some of the older equipment it’s a little harder to fit emergency brakes on so when you do the modernization and you put an entirely new AC PM motor on it comes equipped with all the safety mechanisms that you’d require.


So here at five Penn Plaza we selected this equipment to provide the owner with a better and faster floor to floor times, more accurate and repeatable floor stops, very smooth takeoff almost un-perceptible. There’s a feature in the KEB Drive that permits us to do a fancy word like synthesized pre-torque which, when adjusted properly with the imperial machine and the brake, gives you an an almost a feel that you can’t take the car taking off. This will give the building owner and his tenants a beautiful ride quality. So in addition to the energy-saving and the ride quality were also able to reduce downtime.

EtherCAT Relay IO Module from KEB


The EtherCAT Relay IO Module is the newest addition to the KEB Automation catalog of products. The Relay IO module combines a pilot relay with an IO module, providing the functions of two blocks on a DIN rail in the space of one. At only 25mm wide, the Relay IO module is a great space-saver in any installation cabinet.


Full transcript

KEB’s EtherCAT relay module is the most recent addition to our I/O family.


The module is used to interface with both 120 volt and 230 volt AC field wiring. Typically a power contactor is signaled by a pilot or control relay. Traditionally the pilot relay is connected to an I/O module which then receives signals from a push-button, a sensor, or via the PLC. The signal going through the pilot relay will trigger the contactor to turn the load on and off. KEB’s relay module combines the function of an I/O module and DIN-mounted pilot relay.


When multiple loads are required you save significant space on the DIN rail by removing pilot relays and consolidating up to eight loads into a single module. Similar to other KEB I/O blocks the relay module measures only 25mm wide and has pluggable connectors. It is DIN rail-mounted and mechanically locks into other modules for a secure connection.


The I/O signals communicate from the C6 Smart to the relay module through a high-speed EtherCAT backbone. KEB’s EtherCAT relay module features eight Form A normally open contacts. The contacts are rated two amps each for inductive loads and five amps each for resistive loads.


The relay module is UL-listed and available for immediate sale.

To learn more about KEB and our EtherCAT Relay IO Module visit the Contact Us page on the website. Fill out the contact form or simply give us a call and we’d be happy to answer your questions. Thanks.


Non-proprietary Elevator Controllers & Drives – KEB Machine Room Vids #02


The second video in our series of Machine Room visits. In this episode, we discuss non-proprietary elevator controllers and the advantage of using KEB elevator drives.


Advantages include: all needed tools for adjustment, documentation to aid support, designed for long product lifecycle, etc.


Check out the first video in the series on our YouTube channel.


View full transcript

So non-proprietary controllers are controllers that have been designed to be maintained and serviced by any number of parties. They’re not closed or restricted as far as the information and who can service them.


So today we’re at an application, this is an MCE controller, an I Control. MCE is one company that provides non-proprietary controllers. So this is the KEB elevator drive and R6 line regen unit. Everything ships with the drive that’s needed to service it, install it, maintain it. All the adjustments can be done right on the drive itself so there’s no proprietary cables or dongles. The keypad is central so through the keypad all the adjustments that are needed can be made. Additionally, diagnostics can be reached there without any sort of additional tool.


If you want you can connect to our software. The software is free and it’s available for download on our website.


A second distinction to make is in the hardware itself. This is not special hardware, it’s based on standard industrial drive hardware that KEB uses in other applications worldwide. The F5 series is built on standard industrial drive platform for KEB, which means that it’s been designed for a long product lifetime. KEB shoots for twenty years in the product lifetime. The F4 series which we just discontinued was over twenty years. The F5 series is going on fifteen years and still has a long life. So that’s definitely one important consideration – is the product going to be available and maintainable, not just today but in the future?


One other important distinction as far as documentation and support. Some systems can be pretty closed as far as who has access to the information – what different parameters do, different things like that. By philosophy KEB is very open, so every drive would ship with a manual basically that has this information. It’s not closed information that’s just available to KEB employees or anything like that so it helps in cases where the job might change hands or somebody else might be servicing the elevator than originally installed it.


So if you have any questions about KEB’s integration into non-proprietary elevator controllers you can contact us here or give us a call. Thanks.


EtherCAT Stepper | BLDC Module – KEB America


KEB’s EtherCAT Stepper BLDC Module is the newest addition to the KEB IO family. This compact module brings stepper and brushless DC motor control to the DIN rail.


It is rated for 5 Amps nominal and up to 15 Amps peak. It is UL listed to 42 VDC. Inputs are available for limit switches and encoder feedback. Additionally, a brake output is available. Units are programmed according to the CiA DS402 motion profiles


Read the full transcript

KEB’s EtherCAT stepper module is used to operate both brushless DC and stepper motors.


This compact module measures only 25mm wide and easily expands onto other C6 I/O products.  It is capable of 5 amps nominal current and can reach up to 15 amps peak for brushless DC motors.


For motors with a brake, the module can handle the brake control and a half amp output is available for powering the brake.


The stepper module can run motors ranging from 12 to 72 Volts DC and is UL listed up to 42Volts DC.


The unit uses the CiA DS402 motion control profiles so standard homing, velocity and Torque Modes are possible.  Positioning modes are also possible when using the encoder and hall effect sensor inputs.


Additional programmable I/O is available for wiring limit switches and other required sensors.

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