On 11/26/2014 5:59 AM, Viesturs Lācis wrote: > Yes. Is there a way to run them in series? > Currently I am trying to get one motor to work - still the same issue > of VFD not going higher than 8-9 hz.
In series each motor will see 1/2 the voltage. In parallel they get the same voltage but only 1/2 the amperage. As others have stated you *can not use* any feedback sensing such as sensorless vector. IT WILL NOT WORK with two motors on a single VFD. Study the VFD's manual to find how to turn off all the sensing and feedback functions. You probably won't even be able to use the VFD's overcurrent protection. Put a circuit breaker in line to each motor. Yet another use case for a dead simple VFD or phase converter with next to zero fancy functions, which if such is available costs more than the VFDs with 100+ configurable settings. Pay more to NOT get things you do not want or need. :P What I'd like to have in a solid state phase converter. 1. Not variable. Just a switch or jumper for 50/60Hz. Possibly with the option to convert between those two frequencies in case of RPM critical equipment. 2. No ramp up/down. Or a fixed time ramp with switch or jumper to disable. 3. Remote switch terminals with switch or jumper to configure for start/stop or FWD/Stop/REV switches. Stop also connects to E-stop circuit. Make the voltage right for computer/digital control. TTL level? 3.3V? Whatever is required. Perhaps a switch or jumper to select. 4. Display, one red LED and one green LED. Solid green = All good. Solid red = uh-oh. Press and hold the built in Run/Stop and Reset buttons to blink trouble codes that have a chart printed on or molded into the housing. Dead simple, caveman easy to install. Flip 4 or 5 switches, connect wires and done. Not one gee whiz look what this can do feature most people will never ever use because their old machine or modern day new build does not *need* variable speed. On my Monarch 12CK with 1940's vintage GE 3HP motor I never vary the speed from 60Hz but had to deal with a PITA to get the settings right TECO VFD. Tweak and adjust over and over until it would soften the start just right to quit popping the overcurrent protection. Couldn't get anywhere with it until I switched it from sensorless vector to Volts/Hertz mode. At least it saves the settings in non-volatile memory so I can shut off the power when the lathe isn't in use. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
