Danfoss VLT Variable Frequency Drive Exposed

A dysfunctional tour of an dysfunctional Danfoss variable frequency drive!

Feel free to post constructive comments on what parts are what or how it works, none of this "you don't know what your talking about" crap pls ;)

One of many I've had as scrap, this is a mid-size one. some are so big and heavy they come on their own separate pallet!.

Category:

Science & Technology

Tags:

• Danfoss
• VLT
• VFD
• Variable
• Speed
• AC
• Drive
• Phase
• Motor
• Electric
• VSD
• Frequency
• Control
• Electronic
• Inverter
• DC
• Rectifier
• SCR
• Diode
• IGBT
• Insulated
• Gate
• Collector
• Bipolar
• Transistor
• HVAC

[kevvywevvywoo]

The chokes are there for radio emissions compliance, they arent necessary for the actual function of the drive. The little white critter is the 3-phase input rectifier. There is a sticker on the front that says 'decanter feed pump'. They use those in Sewage Treatment Plants but also Fruit Juice factories, it's part of a centrifugal seperator. Either way i hope u washed your hands before eating your sandwiches!

[Aussie50]

@kevvywevvywoo yeha I've learned a lot about these drives over the last 12 months!

lol yeh some are from treatment plants, I always wash up after handling old junk regardless.

[bakupcpu]

Those 3 big thing are probably dual mosfet or transistor the 3 phase rectifier should be around thought. And yes they send a semi sine wave to the motor those 3 big round thing are RF choke to prevent high frequency to make false reading on the amp mesuring device. Hope i brought some help.

[Aussie50]

@bakupcpu Thanks for the tips, IO have learned a lot from making this vid.

the 3 bricks are Insaulated Gate Bi-Polar Transistors and the white thing I held up towards the end is the rectifier that feeds them

[mrnewagemotor]

THANKS ! I learned more about the internals of a VFD than my entire 3 1/2 year career as an industrial processing equipment mechanic taught me - even going to classes at company expense. I would love to have those diodes and hook them up to a 555 circuit with a 0-5 ohm pot to use as a reverse style DC motor controller to run a DC motor. Would that work ?

[Aussie50]

@mrnewagemotor I'd never dealt with a VFD before I did this vid so you might want to see some of my more recent ones for more info.

the 'diodes' are actually IGBT bricks, but in theory you could control the output pulse width to drive the motor.

I'm not sure about building a DC drive from scratch tho.

[tyreza79]

wowow; ok thats a master piece: you could covert it in to a very strong induction heater: which it very useful

wow variable frequency ?

how much is the frequency variabilty ?

[alfareifaldy]

o I like Danfoss inverter

[tech4156]

saw these guys on tv in the uk, they scammed customers who ended up paying £1000 more than they should have, then they refused to answer the reporters questions or give money back.

[olestetter1]

And a VLT 3008 is a 5.5 kw unit...

[olestetter1]

@bakupcpu The 3 big round things are coils for protection for the IGBT output stage. They limit a sudden currentflow. The RFI coils and capacitor are situated on the dc bus side( the board with the big white capacitors).

[bakupcpu]

@mrnewagemotor yes it would. but you going over the extreme ^^ those thing are normaly rate for high amp.