[sierra4sport]

Had a new Hitachi SJ200 VFD smoke this past weekend following a couple of successful (uneventful) initial test-runs.
The unit smoked immediately upon power-up but had run several minutes the day before without issue - the drive has a total of less than 15 minutes time on it... Appears that an internal power resistor smoked (most likely part of the inrush limiting circuitry)... A google search revealed at least one other person looking for the EXACT SAME part for a Hitachi VFD on a Polish electronics forum... Also have seen other posts here on CNC zone where there may have been similar circumstances (although some involved questionable connections & didn't work upon 1st power-up checks).

Thanks,
Chris

[mactec54]

sierra4sport

Can you do a photo of your input power connections, are you using single phase 220V or 3 phase

[sierra4sport]

Hi,

Input power: 240VAC between L1 & L3/N... I read the manual AND the discussions here...

Chris

[jlnading]

So your running 3 ph 240? Could have a high leg of the 3 ph connected to a place you would not want it connected to, especially controls.

[mactec54]

sierra4sport

why I asked for a photo is I think you have wired the input power to the wrong terminals, when you said you wired L1 & L3/N it should be R/L1 & T/L3 they do have some different labeling of terminals on some of the different models, But should not be on the L1 & L3/N terminals

Your wires should be on the same level of terminals as what the motor wiring is on, if they are not then you will smoke the drive

If your wiring is correct then you should be sending it back for repair or replacement

[sierra4sport]

Hi Jeff & 'Mactec54' - Single phase AC, connected to the correct terminals - I'm not near the drive right now, so won't be taking any pictures.
The drive was connected correctly, ran the motor a couple of start-stop cycles with varying frequency.... No changes, the next day the unit
smoked upon power application. Hitachi says 18mo warranty from date of purchase - I'm asking them to make an exception since the unit is
'new' (purchased and sat on shelf) - hour counters will show total hours under power are zero (assuming the 5-10 min max run time on Saturday
doesn't 'round up' to 1hr).

Chris

P.S. Refer to pg 2-20 of the manual: http://www.clrwtr.com/PDF/Hitachi/Hi...-AC-Drives.pdf (one source)

[Al_The_Man]

Hitachi state that L1/R and L3/T is to be used for 1ph, if the phase loss detection was activated, L3 can be jumpered to L2, to prevent the alarm.
The only reason for the N is for countries that have 240v 1ph and Neutral such as Australia & UK etc.
As far as the VFD is concerned, there is absolutely no difference.
Al.

[mactec54]

sierra4sport

If you wired it to the PDF page 2-20 that is incorrect

2-19 is the correct way to wire it, if you wired it as PDF page 2-20 you will get smoke from the drive

[Al_The_Man]

BTW, the N I was referring to is the occasional use of N where the L3/T label is, NOT the N label BELOW the R,S,T, inputs.
Some are misleading.
Al.

[dan_barber]

Hitachi SJ200 Series has been obsolete at least for 5 years. Current comparable model is WJ200.

[sierra4sport]

Turns out the initial diagnosis for the failure was correct - 'smoked' inrush limiting resistor...
The resistor was 'toast' - it was a 'hybrid' device, has both a resistor and thermal fuse built-in.
Was able to obtain a replacement resistor and replace the smoked unit. Drive functions as
intended... Has been installed on vertical mill setup & is working fine. If anyone else has
this same failure mode on this model inverter, let me know - maybe I can help you get your
inverter working again.