400 HZ Supply

[farrokh747]

Hello all,

Here's a note on my quest for 400hz supply :

After a long search for economical solutions for this, I discovered the ACS 335 series of motor drives made by ABB -- the solution turned out to be far simpler than i thought -

Myth 1: 400hz power supply converters are crazy expensive
Myth 2: You need 3 phase power supply in your pit to drive the converter
Myth 3: you need to source these units from the aviation world - and therefore $$

ABB makes several drives that suit builders looking to motorize seats, etc
The ACS 355 series offers many flavors:
http://tinyurl.com/7dmuvtw
http://tinyurl.com/7292uyh
You can select the current rating according to your needs - after hooking up my 355, i saw that each seat fwd/aft motor drew just .2 amps - moving both seats together drew .4A - For most uses a 5 A unit would do fine

The unit runs on a single phase domestic line, a 15A outlet is good enough - the output is a 3 phase completely programmable supply (Voltage/freq) -

This also opens up the doors to run many acft items that also run on 3 phase 115v 400hz like in-line blowers, etc - for OEM items that need a single phase 115v/400hz supply, you can use just a single line from the unit

The unit I bought has a capacity of 9Amps, far more i realized than i needed -

The Seat motors need 220V phase to phase - but pl check the specs on the units you have - also you'll need to get the pinout of the seat connector - it's usually a 5 pin connector, with 1,2,3 as phase and 4/5 as neut/gnd -

The version of the 355 i bought here locally from the dealer cost me appx 400.00 USD - note that this is an imported item here, so the cost would be less in Europe or the US

The units with a lower rating would be less than that - I was quoted 250USD for a 5A one

cheers!

FC


!! Please check your country voltages for correct unit, or else ka-boom!!

[Matt Olieman]

@farrokh747, Excellent information, thank you!!!

Matt Olieman

[brianwilliamson]

Not sure if this is exactly the same, but the price seems very good:

http://www.ebay.com.au/itm/VARIABLE-...item43ab2b6342
Regards............Brian W.

[farrokh747]

yes, looks like this will work as well - i went with a branded one just in case..... replacement seat motors are not easy to come by! .... but that's the idea, to look for motor drives and not transformers.... I'm amazes me how inexpensive these units are...

[farrokh747]

Added note of caution:

For those of you with acft seats with motors -
When operating your motor drive, ensure the fwd/rev button is set to FWD - in most controllers, this is on the panel, next to the start/stop pushbuttons, and can be pressed by mistake, setting it to REV - this will reverse the seat movement in relation to the movement control toggle switches, and with the phases changed, the seat's internal wiring can now bypass the limit switches, causing the seat to jump the end stops and cause damage -

IN any case, REV phase changes will cause erratic issues with the seat

cheers!

[verticallimit]

A very good idea is to use shielded wire from the frequency inverter and out to the electric motor, etc. And get a good grounding. The voltage will be chopped to pieces by a high frequency (switchmode) and pieced together again to 400 HZ and this can cause unintended electrical noise.