Siemens Micromaster 420 As Motor Controller


2010-08-14 11:16 pm
A couple of things that the article does not mention is whether with the MicroMaster you can dispense with the Eddy Brake on the 401 as the controller would set the speed? Apparently Loricraft always reckoned that removing the Eddy Brake improved the sound of the 401.

Also do you adjust the speed of the deck 33/45 with the controller or does it still require the pulley to be moved as on the original deck?
The strong HF magnetic field arround the motor coils and rotor can reach the magnetic pickup generating a signal of both low rectangular waveforms and the PMW to control the current.

Also the output of this stuff is intended for 3 phase motors, running usually at 380V. So applying this voltage to the motor will blow the coil. Also, if the motor if of the phase split type, there will be no severe malfunction, but the motor uses a capacitor to run, the cap will overload the driver outputs possibly damaging the cap, the motor and the driver. Also, the PWM carrier (again, in the order of 3-4KHz ussually) may cause a overheating in the iron core because of the eddy currents generated at so high frequencies.
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2007-12-01 11:21 pm
I use those at work (hundreds of them) and just this morning I was programming a couple of 440 I hate Siemens stuff is so complicated 300 + pages installation manual and a further 340+ pages parameter manual. If you get one make sure you price all the bits you need as Siemens charges for everything For example you will need the programming unit.
IMO I like Mitsubishi and those are easier to use

I am pretty sure they can do the job but I would worry (see Osvaldo posts) about the noise they may introduce on a domestic mains which will find is way to your Pre/ amplifier is not going to be just magnetic field and you may nedd a few bobs for EMC filters and such

The idea is quite interesting and if you need help Just PM
One needs to set P0003 to 3 to gain access and P0004 to the required data set even before you start

I wonder if the cash lay out would be justified as one can use a DC motor and any dedicated supply already in use on TT
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