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Jeff Raefield

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Jeff Raefield


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RE: can I change the direction of a PowerFlex 70 using a digital input?

Posted By Jeff Raefield Jan 09, 2024 11:53:00 AM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
I'd just like to add, from (unfortunate) experience; Be CAREFUL with how you implement the command for a direction change on a web application. If you simply connect a selector switch to the input, then someone flips that switch while it is running, the VFD will stop and reverse direction, which causes ...

RE: Poweflex 525 online changes

Posted By Jeff Raefield Sep 13, 2023 01:24:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
But just to make sure you understand on the ADC issue; the VFD will not "push" any changes up to the PLC memory used for ADC. That must be done in the PLC program. So if you make changes on the VFD and do not go into the PLC program to SAVE those changes, ADC will overwrite the changes made in the VFD ...

RE: Powerflex 755 Electricity Shutdown Parameter Problem

Posted By Jeff Raefield Jul 27, 2023 02:40:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
Hello Emre, Do you have a Logix PLC communicating to this VFD via Ethernet? If so, do you have Automatic Device Configuration (ADC) enabled? I ask because if you are connected via Ethernet to a Logix processor and have ADC enabled, the PLC memory card is storing a copy of the VFD programming. ...

RE: MV Softstarter

Posted By Jeff Raefield Feb 07, 2023 01:21:00 AM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
The 1562E was based on the SMC-Flex soft start controller, adapted to Medium Voltage. When we redesigned the MV soft starters to use the new SMC-50 based controller, the series number was changed to 1562F. There are numerous improvements and additions to the controller with the SMC-50, too many to list ...

RE: PF4 Fault with no errors

Posted By Jeff Raefield Dec 09, 2022 02:06:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
In my experience, this is usually the case when there is no fault code displayed. The removal of a Run command is not a "fault" condition to the VFD. Look for a loose connection, logic error, bad contact on a field device or even a forgotten protective component etc. (just went through that one). ...

RE: Powerflex 525 Test Bench Setup on single phase

Posted By Jeff Raefield Nov 09, 2022 11:03:00 AM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
1/3HP is roughly 250W. You could use a 250VA basic Control Power Transformer for feeding that drive, I've done so many times for testing purposes. ------------------------------ Jeff Raefield ------------------------------

RE: Powerflex 525 Test Bench Setup on single phase

Posted By Jeff Raefield Nov 09, 2022 03:29:00 AM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
If your transformer has an option for 480V, you can use that. Then if the motor is not capable of being strapped for 460V, you can program the drive to be for a 230V motor. It's not great for the motor to do that for a long time because the DC bus will be at around 685VDC, so the PWM pulses are that ...

RE: 10 HP Bucket Modification Question

Posted By Jeff Raefield Oct 21, 2022 08:00:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
Phil makes good points. What you are describing is essentially a "Duplex Controller", but with some important elements missing. If you have only one starter and two downstream contactors, you cannot separate and lock out one without locking out both. So if one motor goes down, you essentially lose both ...

RE: E-Stop Control Circuit Integration and CSA Z432

Posted By Jeff Raefield Oct 05, 2022 08:04:00 AM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
Ouenuga, The use of a Safety Relay with the E-Stop button will satisfy the requirement of needing a separate Reset button input to be able to re-engage the motor starter. However a safety relay alone will NOT ensure that motor power is removed in the event of the motor contactor welding. A Safety ...

RE: Nameplate Details to Overspeed a Motor with PF525

Posted By Jeff Raefield Sep 12, 2022 03:49:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
Is this a centrifugal pump? If so, you must understand that per the Affinity Speed Law, the power required by the PUMP increases by the CUBE of the speed change. So from 50 to 60Hz is 120%, ergo the pump will need the motor power to increase by 1.2 cubed, or 172.8%. For example if your pump uses all ...

RE: Rare Earth Metals in VSD construction

Posted By Jeff Raefield Sep 12, 2022 03:35:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
In Rockwell MV drives, there are two separate designs in terms of the power semiconductors. The PowerFlex 7000 uses devices called SGCTs, (Symmetrical Gate Commutated Thyristors), and in the PowerFlex 6000 we use traditional low voltage power transistors. Both devices are "semiconductors" based on silicon, ...

RE: Does an encoder improve starting torque on a PF 7000 VSD

Posted By Jeff Raefield Sep 12, 2022 03:04:00 PM
Found In Egroup: Drives, Motion Control & Low Voltage Products \ view thread
To be more precise, it cannot make the motor create MORE torque than the motor is capable of, but it improves the availability of the maximum motor torque at an earlier point in the acceleration curve. In sensorless mode, the torque calculations need to see the motor moving somewhat before it can determine ...