Can I use a 3 phase EMC filter as a 1 to 3 phase inverter?

Thread Starter

metiz

Joined Oct 27, 2014
54
I found a brand new Keb EMC filter, 43A. It's 3 phase in, 3 out. I once had a 3 phase motor controller that I could also power with a single-phase line. Can I do the same with this unit? If so, do I hook up L1 and L2 and leave L3 be? I want to sell it but I need to know if it works first. I posted a picture of the unit below.
 

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Delta prime

Joined Nov 15, 2019
484
Hello there :)
Can I do the same with this unit? If so, do I hook up L1 and L2 and leave L3 be? I want to sell it but I need to know if it works first
Take a look at this circuit.
1593343884741.jpg
Such a simple passive filter plays a role of two-way noise suppression EMI RFI ,there are two different modes.
Differential-mode & Common mode
C1 & C2 is differential-mode, C3 & C4 is common-mode,
For the differential-mode signal (here, it is the low-frequency supply current), the magnetic fields generated by the two coils cancel out so the power transfer function of the circuit is not affected.
I just wanted to show you this circuit and how it functions because if you apply a single phase to try to test you will not only die it will hurt the whole time you are dying.
:)
Have a wonderful day!
 

Thread Starter

metiz

Joined Oct 27, 2014
54
Hello there :)
Take a look at this circuit.
View attachment 210894
Such a simple passive filter plays a role of two-way noise suppression EMI RFI ,there are two different modes.
Differential-mode & Common mode
C1 & C2 is differential-mode, C3 & C4 is common-mode,
For the differential-mode signal (here, it is the low-frequency supply current), the magnetic fields generated by the two coils cancel out so the power transfer function of the circuit is not affected.
I just wanted to show you this circuit and how it functions because if you apply a single phase to try to test you will not only die it will hurt the whole time you are dying.
:)
Have a wonderful day!
That got dark in a hurry :p The unit does say it is an inverter, so what exactly is it inverting?
You say it is brand new, so why the need to test it first?
Max.
I got it from a scrap metal dealer. It was in its original packaging, including mounting brackets and whatnot. USUALLY items that I find there, in this state, work fine, but considering it was found at a scrapyard I need to know for sure first before I sell. Other than 3 phase power, is there any other way of testing this? I do have a 3 phase motor controller if that is of any use
 

MaxHeadRoom

Joined Jul 18, 2013
21,387
It could have been an old inventory stock that was scrapped due to company closure etc, heck of alot ends up that way.
It is not labeled as an Invertor, it means it is meant to feed an inverter or VFD.
Max.
 

Thread Starter

metiz

Joined Oct 27, 2014
54
It could have been an old inventory stock that was scrapped due to company closure etc, heck of alot ends up that way.
It is not labeled as an Invertor, it means it is meant to feed an inverter or VFD.
Max.
That makes sense. In that case, can I wire this thing in between my vfd and motor? (I can set the vfd to <60hz) I know it's not exactly meant to do that but if the motor runs, my "does it work" question is satisfied.
 

MaxHeadRoom

Joined Jul 18, 2013
21,387
It is not meant to go on the output of the VFD, only the supply input.
The only thing you use on the VFD output is a 3 phase choke.
Basically you could check continuity between two conductors, both for input or output short circuit, or from input to output for continuity, if you find these OK, then it should work OK, although it does not test some internal filter components that could be open etc.
Max.
 
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Thread Starter

metiz

Joined Oct 27, 2014
54
Thanks. I measured resistance (just continuity, no choke) between the input and output lines and consistently get about 0.5 Ohms
 

MaxHeadRoom

Joined Jul 18, 2013
21,387
As per post #2, there can be different forms of suppression devices internally , intended to prevent the high switching noise from feeding back into the service supply.
Static noise filter.
Max.
 

Thread Starter

metiz

Joined Oct 27, 2014
54
Thanks for the help. If it wasn't for the internet, I probably would've burned the house down 10 times over :)
 
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