Siemens Micromaster 420 for EMT 930st ... converting 60Hz to 50Hz .

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I have a 50Hz 110v EMT 930st but I'm located in North America which is 60Hz. The platter is turning too fast now.:mad: It is not usable.
I don't have the 420 yet. I'm need info. on how it works and how to operate the Micromaster for my EMT. Any info. are welcome.:p

Thanks...
 
I guess any 50Hz regenerator will do. 30W will probably be beyond the capabilities of single chip amps but maybe a parallel combination will be capable of driving a step-up transformer. I have no knowledge of your proposed invertor and how clean is its output waveform. It seems it also has the ability to drive directly 3-phase motors which could turn out to be a real improvement for your turntable. It will most certainly be capable of supplying the required voltage and power at 50Hz without any modifications and it appears to be much cheaper than any decent diy solution.
 
The SIEMENS Micromaster series inverters are perfect for your application : I have successfully converted many EMT 930's by using these inverters. Not only will you solve your frequency/speed problem but you'll end up with a much more quiet and stable turntable, which is the greatest upgrade/improvement for the venerable 930.
The 930 has a 3-phase synchronous motor which can be directly driven by the Siemens inverter,and as the speed is frequency dependent you can adjust it with great accuracy on the inverter.(free varispeed bonus !) You no longer need the crude,noisy and instable speed adjusting brake felt/spring assembly and it can (must) be entirely removed. (one less source of noise). Also, the phase shifting network (adjustable resistor and failure-prone capacitor in the motor box) must be discarded and the motor rewired for pure 3-phase delta mode: you'll need 3 wires going directly from the motor to the inverter. (if the platter rotates backwards just reverse any two of the 3 wires) Now,the motor will be driven by a real 3-phase (120°) voltage which will make it much quieter and happy (no longer need to play with sthetoscopes to adjust the resistor for minimum motor noise !). The Micromaster has a remote start-stop control input which can be controlled by the EMT turntable Off-Stdby-On microswitch for more convenience. I ususally use a 7-conductor screeened cable between the turntable and the inverter. (3 wires for the motor,2 wires for the remote,2 wires for the AC mains supply back to the inverter). The whole conversion/re-wiring process will take you about 2-3 hours and is fully reversible if you keep all the old parts. Then you will need to program the inverter to optimize the parameters for your motor. This can be a little more tedious as there are many many parameters and 3 levels of programming in the Micromaster. The (optional) control panel/display is of course an absolute must for programming and need to be ordered separately. I can't go into full details about this here. Just let me say it's really worth the effort, once you finished you'll have a better,more stable and quieter EMT 930 than new.
 
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Here is the getting started manual for the MM420: http://www.watson-marlow.com/pdfs-global/mm420gettingstartedguide.pdf

And here is the manual: http://www.acpd.co.uk/sei/s/1488/f123.pdf

This is a complicated drive, and seems able to do just about anything you can imagine.

I am intrigued and may acquire one of these not too far down the road.

They are very inexpensive compared to any boutique motor controller and I suspect it probably outperforms them with appropriate 3 phase motors.

Note that these seem to require 200 - 240V input power so a special outlet to power the inverter or a step up transformer would be required.
 
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Typically you have to have the front panel interface installed, then connect mains power of the proper voltage for that model to at least two of the big screw terminals will get you an error message on the front panel.
If you have a 50 hz 120 VAC appliance, then there are different variable speed drives that will convert 120 60 hz to 120 50 hz. Use the 250 VA version for a turntable. If you have a 240 VAC 50 hz device in the western hemisphere, then you need a 240 vAC variable speed drive and an air conditioner outlet 230 VAC outlet, or a 120-240 transformer. These are sometimes sold as "isolation" transformers a little cheaper than a "power" transformer showing 120-240.
The 120 vAC VSD's are useful for stabilizing pitch on a hammond organ running on generator power.
 
There are many brands of inverters Siemens IMO is one of the most complicated expensive and charge for all the optional extras

I like Mitsubishi much better and they are much easier to use and control panel is standard Just goggle up single phase inverter and see what you can get near home.

They are built for industrial use and put out a lot of noise and electrical interference
a EMC filter is one of the possible solutions same have an integrated one.

Mitsubishi Electric - Inverters
Here is link from UK supplier
Buy Inverter Drives D720SC Inverter Drive 0.1kW 0.8A 1 Ph Mitsubishi FR-D720S-008SC-EC online from RS for next day delivery.
Just select number of phases and power rating (1 phase from 100 to 180 W came up with 14 results)
At times they give on the products manual the rating of the harmonic currents
Buy Inverter Drives Sinamics G110 inverter w/filter, 0.12kW Siemens 6SL3211-0AB11-2BA1 online from RS for next day delivery.
this has a filter but look at page 70 of manual 13th gives 0.5 amps with fundamental of 1.8 A it will not cost much more of the Mitzi but there is £26 extra for control panel

No Mather which one you get the manuals are all on line and provided you feel safe working with 240 V mains it takes just common sense and patience.

When setting up the inverter you need to know the motor parameters this may be biggest hurdle
 
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Micromaster 420

Hi there Tubologic,

I have a EMT 930 which is controlled by a 420. Unfortunately, the 420 has packed up. I have obtained a replacement 420 but of course am stumped at setting it up as it looks fairly complicated. Could you possibly set it up for me if I were to send you the new 420 (including BOP).

I am located in Edinburgh, Scotland.

Thanks

Gordon
 
The SIEMENS Micromaster series inverters are perfect for your application : I have successfully converted many EMT 930's by using these inverters. Not only will you solve your frequency/speed problem but you'll end up with a much more quiet and stable turntable, which is the greatest upgrade/improvement for the venerable 930.
The 930 has a 3-phase synchronous motor which can be directly driven by the Siemens inverter,and as the speed is frequency dependent you can adjust it with great accuracy on the inverter.(free varispeed bonus !) You no longer need the crude,noisy and instable speed adjusting brake felt/spring assembly and it can (must) be entirely removed. (one less source of noise). Also, the phase shifting network (adjustable resistor and failure-prone capacitor in the motor box) must be discarded and the motor rewired for pure 3-phase delta mode: you'll need 3 wires going directly from the motor to the inverter. (if the platter rotates backwards just reverse any two of the 3 wires) Now,the motor will be driven by a real 3-phase (120°) voltage which will make it much quieter and happy (no longer need to play with sthetoscopes to adjust the resistor for minimum motor noise !). The Micromaster has a remote start-stop control input which can be controlled by the EMT turntable Off-Stdby-On microswitch for more convenience. I ususally use a 7-conductor screeened cable between the turntable and the inverter. (3 wires for the motor,2 wires for the remote,2 wires for the AC mains supply back to the inverter). The whole conversion/re-wiring process will take you about 2-3 hours and is fully reversible if you keep all the old parts. Then you will need to program the inverter to optimize the parameters for your motor. This can be a little more tedious as there are many many parameters and 3 levels of programming in the Micromaster. The (optional) control panel/display is of course an absolute must for programming and need to be ordered separately. I can't go into full details about this here. Just let me say it's really worth the effort, once you finished you'll have a better,more stable and quieter EMT 930 than new.
Hi there Tubologic,

I have a EMT 930 which is controlled by a 420. Unfortunately, the 420 has packed up. I have obtained a replacement 420 but of course am stumped at setting it up as it looks fairly complicated. Could you possibly set it up for me if I were to send you the new 420 (including BOP).

I am located in Edinburgh, Scotland.

Thanks
 
Hi there Tubologic,

I have a EMT 930 which is controlled by a 420. Unfortunately, the 420 has packed up. I have obtained a replacement 420 but of course am stumped at setting it up as it looks fairly complicated. Could you possibly set it up for me if I were to send you the new 420 (including BOP).

I am located in Edinburgh, Scotland.

Thanks

FYI
http://www.lencoheaven.net/forum/index.php?topic=11817.0
Karel

(Happy owner EMT930 & motor management Mitsubishi S500)
 
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Joined 2004
Paid Member
Not compatible "invertor Siemens 420 & Lenco motor.

If you don't mind doing a little bit of work my single phase regenerator project is here:

http://www.diyaudio.com/forums/anal...rator-induction-motor-powered-turntables.html

Works well with TD-124 and should work great with a Lenco or other similar motors. It can do 50 or 60Hz, and 100 - 120V or 200 - 240V at up to 40VA or so. It uses very inexpensive and commonly available parts, the most expensive individual items are the chassis and transformers required.
 
The SIEMENS Micromaster series inverters are perfect for your application : I have successfully converted many EMT 930's by using these inverters. Not only will you solve your frequency/speed problem but you'll end up with a much more quiet and stable turntable, which is the greatest upgrade/improvement for the venerable 930.
The 930 has a 3-phase synchronous motor which can be directly driven by the Siemens inverter,and as the speed is frequency dependent you can adjust it with great accuracy on the inverter.(free varispeed bonus !) You no longer need the crude,noisy and instable speed adjusting brake felt/spring assembly and it can (must) be entirely removed. (one less source of noise). Also, the phase shifting network (adjustable resistor and failure-prone capacitor in the motor box) must be discarded and the motor rewired for pure 3-phase delta mode: you'll need 3 wires going directly from the motor to the inverter. (if the platter rotates backwards just reverse any two of the 3 wires) Now,the motor will be driven by a real 3-phase (120°) voltage which will make it much quieter and happy (no longer need to play with sthetoscopes to adjust the resistor for minimum motor noise !). The Micromaster has a remote start-stop control input which can be controlled by the EMT turntable Off-Stdby-On microswitch for more convenience. I ususally use a 7-conductor screeened cable between the turntable and the inverter. (3 wires for the motor,2 wires for the remote,2 wires for the AC mains supply back to the inverter). The whole conversion/re-wiring process will take you about 2-3 hours and is fully reversible if you keep all the old parts. Then you will need to program the inverter to optimize the parameters for your motor. This can be a little more tedious as there are many many parameters and 3 levels of programming in the Micromaster. The (optional) control panel/display is of course an absolute must for programming and need to be ordered separately. I can't go into full details about this here. Just let me say it's really worth the effort, once you finished you'll have a better,more stable and quieter EMT 930 than new.


Almost ready a clean Three Phase turntable supply for Papst, EMT 930 .
Measurements following soon ,

Volken


IMG_0853.JPG
 
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