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FAQ – Answers to SmartD’s most Frequently Asked Questions are at your fingertips.
Contact us if you still have questions after reading the following:
General Questions
SmartD’s Clean Power variable frequency drive generates pure-sine electrical signals in a volume half the size that is twice as efficient.
Forget messy cables and bulky filters. Experience Clean Power in a compact footprint.
SmartD’s Clean Power variable frequency drive generates pure-sine electrical signals in a package half the size that is twice as efficient.
Forget messy cables and bulky filters. Experience Clean Power in a compact footprint.
Clean Power VFD will be available for purchase Q3, 2022 in the North American market.
Book a demo. Get the signal you deserve.
3 cables in, 3 cables out. That's it. Set it up and let it do its thing in under 30 minutes. Cable length can be extended up to 300m without the need for expensive shielded motor cables or special cable ducts.
An electric motor’s purchase cost accounts for only 2-3% of its total lifetime cost. The remaining 97-98% comes from the electrical power needed to operate the motor.
Controlling motor speed with a VFD offers energy savings specifically for centrifugal loads such as centrifugal pumps and fans.
When using the SmartD Clean Power VFD, extra components such as huge and bulky filters are not necessary, therefore the energy lost in those components is saved.
Moreover, the clean sine wave output allows for 15% less losses in the motor compared with a traditional VFD.
You can use any AC 3-phase Asynchronous Squirrel Cage Motors, the most common type of motor in industrial applications with the SmartD Clean Power VFD.
A variable frequency drive (VFD) is an electronic device that controls electric motor speed by varying the frequency and voltage supplied to the motor.
A VFD adjusts the motor’s speed to match the load requirement, this helps to drastically reduce energy consumption.
Other names for a VFD are variable speed drive, adjustable speed drive, adjustable frequency drive, AC drive, and inverter.
The Clean Power variable frequency drive is in compliance with EMI/EMC standards, ensured through the use of integrated EMI filters.
SmartD's Clean Power VFD performs where Total Harmonic Distortion is kept below 5%, while power factor unity is maintained. (The industry standard is 99%)
SmartD products are IoT, BMS and SCADA ready. They feature ethernet IP and Modbus TCP connectivity for integration with Cloud, BMS and SCADA systems.
Field test our units and see for yourself. Let's chat about your project and specific needs.
Performances Questions
An electric motor’s purchase cost accounts for only 2-3% of its total lifetime cost. The remaining 97-98% comes from the electrical power needed to operate the motor.
Controlling motor speed with a VFD offers energy savings specifically for centrifugal loads such as centrifugal pumps and fans.
When using the SmartD Clean Power VFD, extra components such as huge and bulky filters are not necessary, therefore the energy lost in those components is saved.
Moreover, the clean sine wave output allows for 15% less losses in the motor compared with a traditional VFD.
The SmartD Clean Power VFD outputs a clean sine wave and embed an Active Front End (AFE). Therefore, with a total distortion of 3% and a power factor near unity, SmartD Clean Power VFDs do not disturb other equipment or systems and far exceed IEEE519 recommendations. And the real sine wave output makes it harmless to motors and cables.
SmartD Clean Power VFDs are rated both Normal Duty and Heavy-Duty, albeit for different current capabilities. For instance, a variable frequency drive able to run a 20HP Normal Duty motor is also able to run a 15HP Heavy-Duty motor.
Applications requiring a high overload tolerance with constant load torque require a Heavy-Duty rating drive; e.g extruders, conveyors, lifting equipment, compressors, or crushers.
In variable torque applications, in which the torque requirements drop along with the speed, a Normal Duty drive will suffice; e.g centrifugal pumps and fans.
SmartD Clean Power VFD is designed to control 3-phases motor, and can not drive a single phase motor. However, SmartD commits to listen carefully to your need, you may need special adaptation of our standard offer. From brand labelling to customized electronic design tell us how we can help.
STO is the acronym of Safe Torque Off. It is a safety feature that prevents a motor from starting or generating torque when it's not supposed to. It is designed to stop the flow of electrical power to the motor or machine, and it can be triggered by a variety of signals, such as an emergency stop button, a safety switch, or a fault detection system.
It prevents machines from moving or turning on when they shouldn't be, to prevent accidents and injuries. Think of it as a way to make sure that a machine won't start unexpectedly and harm someone.
Generator Sizing with AFE VFDs: AFE VFDs, including those from SmartD, have a distinct advantage regarding generator sizing. Due to their efficient handling of harmonic currents, there's no need to oversize associated equipment like transformers and cables.
Impedance and Frequency Variation: Generators inherently have a higher impedance, often referred to as a "weak grid", and may not always maintain a consistent frequency output (e.g., 60Hz) as reliably as the primary grid.
SmartD's AFE VFD Performance: We've rigorously tested our AFE VFDs under conditions simulating weak grids and significant frequency variations using our grid emulator. SmartD AFE VFD can withstand both cases without any issues. SmartD's AFE VFDs leverage their higher bandwidth compared to conventional AFEs, ensuring ultra-fast responses to fluctuating line conditions.
In essence, SmartD's AFE VFDs are robustly engineered to seamlessly integrate with generators, ensuring optimal performance without oversizing.
PF Correction Cap Banks with SmartD AFE Drive: While it's worth noting that PF correction capacitor banks are redundant with the SmartD AFE drive, because the power factor of the Clean Power VFDs is almost equal to 1, let's consider a scenario where they're already integrated into the network.
Impact of PF Correction Cap Banks: The actuation of a capacitor bank creates a transient short circuit. This is due to the energy absorption from the line to charge the capacitor, leading to an immediate voltage dip followed by voltage oscillations. Consequently, the DC bus capacitors of the VFD attempt to charge to the transient line voltage's peak, which can trigger an overvoltage fault or even damage the input diode front-end. Moreover, capacitor banks can induce resonant currents, amplifying the harmonics produced by the VFD.
Comparison with 6-Pulse VFD: The aforementioned issues are predominantly associated with 6-pulse VFDs. The AFE, in contrast, can swiftly respond to voltage dips or fluctuations, ensuring the DC bus remains unaffected. Additionally, the harmonic generation by an AFE is significantly lower than that of a 6-pulse VFD, which substantially reduces the risk of resonant currents.
SmartD AFE VFD Testing: While field tests of the SmartD AFE VFD with capacitor banks haven't been conducted, SmartD has employed simulations and grid emulator tests to assess voltage fluctuations and spikes. The results confirm that the SmartD AFE VFD maintains its performance even in the presence of such configurations.
In summary, while PF correction capacitor banks can introduce challenges, the SmartD AFE VFD is engineered to handle such scenarios effectively, ensuring consistent and reliable performance.
Usage Questions
Trying to match a VFD power output with a motor power rating is insufficient. It is necessary to know the operating environment and the work to be performed. First, select the proper motor according to the load's driving force and the movement cycles. The basic movement cycle is: start > acceleration > constant speed > deceleration > stop. Second, select the variable frequency drive accordingly to its capacity to drive the motor previously selected: ability to drive the starting torque during acceleration phase, ability to consume the regenerated energy during the deceleration phase, overload capacity complying with the application.
In north America, fuses are required for branch circuit protection per NEC (One fuse per phase). In most of other areas, the IEC rules must be fulfilled and fuses of characteristic gL (general-purpose fuse link for cables and lines) and gG (general-purpose fuse link for general installations) protect the lines in the frequency converter system. To protect the semiconductors in the frequency converters, you can use fuses of characteristic gR. Recommended fuses type and sizes are given in the user guide that can be downloaded from this website.(link:
When working with a VFD, you need VFD cable that can handle the drawbacks from the PWM signal generated by the VFD to avoid motor and equipment failure. However, thanks to the clean sinewave generated by the SmartD clean power VFD, means to mitigate VFD's issue are useless. You can use standard motor cables, and size them according to the user guide recommendation and local regulations.
When the VFD needs to be controlled remotely (away) (example: from a control room using digital input and/or analog inputs, or from a remote system/device (PLC, DCS, network…) this is the remote control mode. In other words, the commands are coming from a system or a human being not close to the VFD. When the VFD needs to be controlled from its front face HMI or locally with a connected SmartD App(commissioning, maintenance, test, …) the user does not want any remote action to interfere and start a dangerous operation while working locally on the VFD. This is the local control mode. In other words, there’s a human being close to the VFD, who controls the VFD.
The switch between remote and local is a user (human being close to the VFD) action. It can be done either by a command from the HMI or by a digital input assigned to this function.
Detailed explanations of those 2 modes and VFD behavior are available in the SmartD Clean Power VFP user guide that can be downloaded from this website (link:
- Using the mobile app create a offline configuration with the desired attributes.
- Export the configuration from Mobile to your laptop
- Place the configuration onto a USB thumb drive
- Rename the the configuration file to “smartdrive-config.json“
From the HMI select Menu-> Configuration & date → Import from USB-> Yes
Yes, you can mount the HMI to the outside of the enclosure using the mounting holes on the back of the screen and a shielded ethernet cable (RJ45 connector) to your desired length and up to a maximum of 5 meters.
Ordinary VFD inputs are not sensitive to the 3 phases’ sequence of the grid. However the Clean Power VFD embeds an Active Front End (AFE) that feeds the grid with regenerated energy when the motor is in deceleration mode. This regeneration must be done and synchronized properly on the 3-phase power grid. Therefore the Clean Power VFD must be wired to the power line in direct sequence.
Maintenance Questions
Keep the VFD dry, keep the VFD clean, keep all connections tight. The routine inspection and annual inspection are described in the user guide that can be downloaded from this website: https://smartd.tech/downloads/
If you have more questions please contact our sales team.
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SmartD Clean Power is real and it is ready to revolutionize motor control. Don’t just take our word for it, see it for yourself and eliminate all questions from your head.
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