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View Full Version : Apparent issue with SJ200 & Leeson 3ph 2HP motor



haysys
02-07-2007, 03:33 PM
Hi All,

Prior to the recent holidays, I acquired a Hitachi SJ200-022NFU (capable of accepting 1 and 3 ph line power) and a Leeson 2HP 3ph 3400RPM motor.

I have 240 1ph service into the shop via a subpanel breakered at 60A at the main panel. Until now, the breaker feeding the subpanel has never tripped.

I connected the line and load wiring precisly as defined in the manual (2 legs of the 240 line power going to L1 and L2 and neutral going to the N/L3 lug while the VFD to motor connection is U to U1, V to V1, and W to W1). I also have the chassis ground of the motor connected to the chassis ground of the VFD. As my line power receptacle does not currently have a ground lug, I left the line side of the VFD ungrounded. I'll get a ground wire and appropriate recptacle prior to actual install and operation.

After double checking my connections, I plugged the power plug into the wall socket and shop immediately went black. None of the local subpanel breakers tripped, but the the 60A breaker did. This was an instantaneous, do not pass go event.

I have since looked over everything again, and all connections seem to be preceisly as they need to be. I have checked for shorts in all of my cables and plugs--all are as prescribed. I also checked the 240 circuit and everything checks out voltage wise.

I am stumped and unsure what to do next. I'm reluctant to plug it in again because I have changed nothing since the trip. I could sure use some advice. I am definitely out of my element here.

Thanks,

David

Al_The_Man
02-07-2007, 05:04 PM
I have never heard of connecting a VFD up with the neutral when using 1 ph, I think if you check the manual, the L1 & L3 is used for the 240vac, you may need to jumper the L1 & L2 terminals, Also Do you have a jumper in place now?
Al.

haysys
02-07-2007, 05:52 PM
Well... that would explain my problem wouldn't it. I feel absolutley stupid.

There is indeed a jumper between L1 and L2 and I heartily questioned that--the idea of connecting the two legs of 240 across the jumper defied my understanding of what made sense. But the docs are quite clear that the Jumper must be in place... and I have opinions about people who blindly follow along without questioning. Duhhh...

And indeed I did not intepret the instructions to hook the 2nd leg to N/L3. There were no examples for connecting 1ph power. I did just reread the docs and it does indeed say (in bold no less):

"...for single phase power, terminal [S/L2] will remain unconnected." Now it makes sense.

One final question then: Is the neutral connected to anything? Or does it just float?

Thanks for your attention Al. You have answered hundreds if not thousands of questions here, and I'm quite certain that we all greatly appreciate the energy and knowledge you so generously share.

Thanks!!!

David

mactec54
02-07-2007, 07:40 PM
Hi you sure do have a problem you my have fryed the drive as well
The L1 & L3 are what you have to use for your single PH 240 input
L2 you do not connect any thing to it

Some drives L1 can be jumpered to L3 but I'm not sure with your drive
Yaskawa you can

The neutral was one of your problems as you created a dead short
and do not jumper L1 & L2 that to could be a dead short

You can use the Neutral as a ground wire if you do not have a ground but put some green heat shrink on it

Do not run the drive without a ground to the power source you are just
asking for trouble or Electrocution I'm surprised that AL The Man did not say
this by wiring this way you made your whole machine live with no Ground to
protect you.

haysys
02-07-2007, 08:00 PM
Mactek,

Thanks for your response.

Seems like what you and Al said are in contradisction. L1 and L2 have a jumper. As I said in my second post, the docs do say "L2 will remain disconnected".

Anyone else withan SJ200 powered with 1ph?? How did you connect it???

Thanks,

David

Al_The_Man
02-07-2007, 09:06 PM
You can use the Neutral as a ground wire if you do not have a ground but put some green heat shrink on it

Do not run the drive without a ground to the power source you are just
asking for trouble or Electrocution I'm surprised that AL The Man did not say
this by wiring this way you made your whole machine live with no Ground to
protect you.

I did not allocate using without ground, but you do NOT use neutral as a ground wire, ever, this violates the E.Code.
In fact you do not use neutral at all in VFD installation.
The manual states using L1 & L3 for the 240v 1ph. The L1 & L2 are jumpered to allow a bit of extra DC capacity on 1 ph.
The ground is connected in the usual way to the ground lug.
By having a short circuit across the 240v, you probabally blew the breaker before any damage was done.
Al.

JRaef
02-07-2007, 10:53 PM
Connection of the L1 and L2 with a jumper is unnecessary, it gives you no "extra capacity" since all the AC input does is provide the raw power for conversion to DC. The capacity of those 2 diodes will be greater, but the total input capacity is still dictated by the other 1/2 of the circuit anyway, so it makes no difference. They recommend making that jumper connection just to satisfy the people who insist on connecting wires to unused terminals, PRECISELY so that they are not compelled to connect the neutral! Now that you have, you most likely blew the input diodes, i.e. your drive is toast. Sorry for the bad news. The only possible saving grace is if by some miracle, the breaker cleared before the diode popped. Highly unlikely though. In that world, breakers are painfully slow.

haysys
02-07-2007, 10:55 PM
Thanks Al,

Understood and thank you. I'll hook it up tomorrow and let all know if the breaker did the additional job of protecting the unit.

Regards,

David

mactec54
02-07-2007, 11:02 PM
Hi I did type it wrong and I changed it to L1 & L3 for these Hitachi drives should be connected for 240 V single PH and AL you can use any wire you want as long as it is correctly colored or marked so it is clear what that wire is, this does not Violate any codes.Also as J Raef has said you do not have
to jumper L1 & L2 for it will have no gain

Yaskawa VFD Drives are L1 & L2 for single PH

Al_The_Man
02-07-2007, 11:17 PM
The blocking action of a 3 phase bridge should cause no conduction from live to neutral if a neutral was so connected to a phase input.
My point about the ground was that you violate the code if you use the neutral as a ground.
The system neutral should be only grounded at source, and this applies to local supplies where a local neutral is set up.
The only reason I mentioned the link was to quote the manual for David's information.
It probabally does not matter what pair you use, as the input usually enters to a 3 phase bridge, the alternative is where there is a 1 phase ac control source connected to a particular pair.
Al.

haysys
02-08-2007, 08:53 PM
Hi all...

I went to the shop and hooked up everything from scratch, with the two legs of my 1ph 240 to L1/L2 (jumpered) and L3. I clipped and wire-nutted the neutral wire. I also ran a dedicated wire from the VFD ground to Earth ground. The 3ph motor is hooked up as previously stated (U,V & W plus ground).

I plugged the VFD in and... (drum roll) the breaker tripped again.

So unless anyone has any other thoughts, I suspect I cooked the VFD. I think I'll call Hitachi tomorrow, bare my soul, and see what can be done.

Thoughts???

Thanks again,

David

Al_The_Man
02-08-2007, 09:16 PM
Doesn't sound good, try powering up without the motor connected, just to confirm if it is the supply input problem.
Al.

wildcat
02-08-2007, 09:27 PM
I have exactly the same configuration as you... well except I have a real ground. Please see the attached image to see how it is configured. I did not change any jumper. There is a jumper installed but on the second row of terminals - you can see the jumper on pg 2-19 of the manual and in the picture. I hope you find there is nothing wrong with your VFD.

haysys
02-08-2007, 10:24 PM
Hey Wildcat and Al,

Well, this continues to be a damnable and humbling experience. I work with tech stuff every day, and I have never so misread (maybe not read is more apt) a manual as I have this one from Hitachi.

I was going back through the manual, looking at diagrams, and suddenly began to question what I was calling L1, L2, and N/L3.

Then Wildcat simultaneously posted his picture and served up my second helping of humble pie in as many days.

To make a short story as short as possible, I was using the second row of lugs, not the first. I read the schematic to mean that the 1st row was used for 3ph input and the 2nd row for 1ph input. Now, I realize that is rather lame reasoning on my part, but that is what I did. I now see that the top row is for braking. If I could find a smiley that fits in here I'd use it, but they're all way to understated to fit the situation.

I must say though, no where does the manual say to leave the Neutral wire disconnected from the VFD. I'm happy te eat my 3rd helping if someone can show me where it is. Here's the URL to the manual:

http://www.hitachi.us/supportingdocs/forbus/inverters/Support/sj200ebook_NB650XA.pdf

So, the first opportunity I have to get back to the shop, I'll hook this thing up again and see what happens. Hopefully I didn't burn something out hooking it up to the braking circuit.

Seriously, thanks for all of your help and best wishes.

David

wildcat
02-08-2007, 10:42 PM
David - hey, just cause mine is working does not mean there were not initial problems :) That manual is THICK and you are right, there is not much (is there any?) information on hooking the VFD up to single phase power. Somehow I did notice the warning on the side that said to be sure to check the model number... turned out I was initially sent a -002 instead of a -022... Hmm, think a 1/4HP VFD would drive a 2HP motor? Anyway, best of luck. Be sure to go through the programmable variables and set them appropriately for your motor. VFDs are really pretty amazing beasts.

Al_The_Man
02-08-2007, 11:14 PM
You are going to be very lucky if you haven't fried the Braking circuit.
I would hook it up the CORRECT way without the motor connected and see if any fault codes come up,
Al.

haysys
02-10-2007, 05:17 PM
Hi All,

Just a quick post to bring you up to date on the status of my VFD. I connected the unit (CORRECTLY) without the motor connected (the two legs connected to L1 & L3, no neutral connection, and the ground lug connected to earth.

The unit did not light up at all, and I got a small puff of magic smoke.

I'm certain I've cooked this thing. I'm going to contact a repair facilty for an estimate of the cost to repair. I won't be surprized if the cost is close to the actual cost of the unit. If you have a thought on this, I'd be happy to hear it.

I'm fairly disgusted with myself, but I'm beyond anything more than a shake of my head and writing a check for another one. Expensive lesson, but one well earned. Ha... that was supposed to be learned, but I think earned is equally apt.

Thanks for your help and patience!!

David

wildcat
02-10-2007, 11:21 PM
Oh man real sorry to hear this. Good luck with the repair quote. I'd be inclined to just get another one... after holding back a tear or two. FWIW, I got mine from Automation4Less which, at least at the time, had the best deal going that I could find. Also, I am a little uncomfortable about turning the VFD on without the motor attached. I could swore I read in the manual not to do this but couldn't find it the other day. I might just be misremembering the warning about placing a switch between the VFD and motor.



I'm certain I've cooked this thing. I'm going to contact a repair facilty for an estimate of the cost to repair. I won't be surprized if the cost is close to the actual cost of the unit. If you have a thought on this, I'd be happy to hear it.

Al_The_Man
02-10-2007, 11:45 PM
Also, I am a little uncomfortable about turning the VFD on without the motor attached. I could swore I read in the manual not to do this but couldn't find it the other day. I might just be misremembering the warning about placing a switch between the VFD and motor.

I think thats what you are alluding to, is that it is not recomended to remove and apply power to the motor in the motor leads.
Its Ok If you power up a VFD as long as you do not connect a load when power is on.
Al.

bilinghm
03-21-2007, 10:51 PM
I too have a Leeson 2HP motor and an Hitachi SJ200-015NFU VFD sitting on my workbench ready to install. The description of the mistakes made has me re-reading everything in the manual and sweating bullets! Wow, these are really poor instructions for wiring with single phase 240V! Actually, there really isn't a wiring diagram at all for 1 ph.

So if I have this right, with my 4 wire 240 line, the red(or black) goes to L1, the second hot wire goes to L3, the green to the grounding lug on the VFD chassis, and the white wire goes to NOTHING. Is this correct? Is it advisable to connect L1 and L2 with a "jumper" or not?

Also, should the motor chassis be grounded back to the VFD chassis ground lug as well?

Thanks,

Bill
Atlanta

Al_The_Man
03-21-2007, 11:03 PM
The grounds is normally connected to the Ground lug on the VFD and then carry on through to the motor frame.
I don't think it will be necessary to put the jumper on as it does not really do anything, as long as you connect just the L1 & L3 to the 240v, the neutral is not connected.
I think the previous damage was cause by wrong hook-up all together (wrong terminals strip).
Al.

wildcat
03-21-2007, 11:15 PM
I think a picture of a working 1ph 220V hookup was posted earlier. You should compare that picture against your setup.

bilinghm
03-22-2007, 09:04 AM
I have studied your excellent photo. It appears that you don't use a "jumper". I will wire mine exactly like yours. Thanks!


I think a picture of a working 1ph 220V hookup was posted earlier. You should compare that picture against your setup.

wildcat
03-22-2007, 09:59 AM
I have studied your excellent photo. It appears that you don't use a "jumper". I will wire mine exactly like yours. Thanks!

There is a jumper on the second row of connectors on the left most side of the group of three (pins named +1 and +). Looking at page 2-20 of the SJ200's manual you will see this jumper connecting the pins in black (versus the pins in white where you make your power connections. Just don't confuse these pins as with the bottom most row. The diagram is a little confusing really... they tried to pack too much on the page. You can also see the jumper in the photo on page 2-22. For me this jump was installed when the 3HP SJ200 arrived. It's probably on yours already as well.

bilinghm
03-22-2007, 03:36 PM
I examined my VFD and I see the jumper to which you refer. It is a small sheet metal bridge that permanently connects the first two terminals on the left on the second row. It was my understanding that the second row of terminals were not a part of the power wiring diagram, but are associated only with braking functions.

There was some discussion of creating a wire jumper to connect L1 and L2. I now see that the "jumper" that appears on the confusing and inadequate wiring diagram from Hitachi is actually the factory installed treminal bridge you have pointed out. Mystery solved! Thanks!


There is a jumper on the second row of connectors on the left most side of the group of three (pins named +1 and +). Looking at page 2-20 of the SJ200's manual you will see this jumper connecting the pins in black (versus the pins in white where you make your power connections. Just don't confuse these pins as with the bottom most row. The diagram is a little confusing really... they tried to pack too much on the page. You can also see the jumper in the photo on page 2-22. For me this jump was installed when the 3HP SJ200 arrived. It's probably on yours already as well.

PaulCurtis
03-26-2007, 10:51 AM
The three phase inputs of the SJ200 are totally symmetrical, so technically, single phase can be connected to any pair of terminals. The reason jumpering to the "unused" phase is required in some inverters is to because they have loss of phase detection. Adding the jumper fools the drive into thinking there are 3 phases present.

As for the drive that had power wired to the second terminal row, it is probably damaged beyond economical repair, unfortunately. We have noted that the single-phase wiring details could use some beefing up, and we will do this in the next revision of the manual. If you have questions, please call Hitachi's Technical Support Line at 914-333-2900.

Paul Curtis
Asst. Product Manager, AC VF Inverters
Hitachi America, Ltd.

mactec54
03-26-2007, 02:56 PM
Hi Paul great to see Hitachi Product Manager on this site.

I think there is a biger problem as the drive wires L1 L2 L3
were not used the power was applyed to the +1 + -
where you would put your Braking resistor I think that is
were the jumper is that was being talked about. I may be wrong
on this but thats how it reads in the differant posts I have
read

bilinghm
03-27-2007, 09:22 AM
Last week I sent a letter to Hitachi about the confusion associated with their instructions for single phase hook up of their VFDs. I directed them to this discussion thread and asked then to respond. They immediately sent me this attached PDF file. I see that they have also written a post to the group. This is very good to see.

bilinghm
03-27-2007, 09:26 AM
Here is the personal reply I received from Paul Curtis. See my original letter below.

Dear Mr. Cunningham,

Thank you for your recent email. While we deeply regret any confusion you had, we do truly appreciate your feedback. We make every effort to produce a thorough and clear instruction manual. I’m sure you can imagine, preparing a manual for such a product is a complex task, and sometimes details can be overlooked. We value input from customers such as you to continually improve our documentation. We will make sure this matter is addressed in the next revision of our manual.

Again, thank you for taking the time to write to us, and please feel free to contact us if you require any further assistance.

Sincerely,
Paul Curtis
Assistant Product Manager
AC Inverter Products
Hitachi America, Ltd.
Tarrytown, NY
Technical Support Line: (914) 333-2900
http://www.hitachi.us/inverters



From: bilinghm@bellsouth.net [mailto:bilinghm@bellsouth.net]
Sent: Friday, March 23, 2007 3:49 PM
To: #HAL_inverterinfo
Subject: CUSTOMER SUPPORT: Hitachi SJ200-015NFU


You have received a new global support request:

First Name: bill
Last Name: cunningham
Phone: 770-632-5711
Email: bilinghm@bellsouth.net
Country: United States:us_email

From web page:Hitachi Global Support Form
Subject: Hitachi SJ200-015NFU
Product Category: AC Variable Speed Drives

Question: I recently purchased a Hitachi SJ200-015NFU Variable Frequency AC Inverter Drive for use in my home machine shop. I am shocked by the extremely poor wiring instructions supplied with this unit. I will be using the inverter with single phase 240 VAC power. The section that discusses the proper single phase wiring of this expensive and complex unit is approximately one sentence on page 2-19. There is no photo of the proper wiring (as there is for three phase). This lack of information can lead to inncorrect wiring and expensive damage to the unit. You do your product and your customer a disservice with such poor instructions. See a discussion of this at: http://www.cnczone.com/forums/showthread.php?t=32014 You need to do something about this!

QSIMDO
01-13-2008, 12:00 PM
This thread has been of tremendous value to me as I just bought the VFD in question.
Hope everything worked out well for the thread originator.

However, as I was reading the PDF with the info from Hitachi on "Sizing Three-Phase Inverters for use with Single-Phase Supply" I was taken aback by the sentence "The rule of thumb Hitachi recommends is to start with the (motor's) nameplate full load amperage (FLA) rating and double it. Then select an inverter with this doubled continuous current rating."

I'll be driving a 3 hp, 3~ Baldor VM3559T dual voltage motor which, if I'm reading the plate correctly is "7.8-7.4-3.7".

So "15.6" for the motor and the VFD is rated at 11? :confused:

Now I don't really -need- 3 hp, but the motor came so cheap.....ahh well.
So does this mean buying a 2 hp then?

wildcat
01-13-2008, 12:24 PM
Give a call to the Hitachi tech support for clarification. When I talked with them about this they said that derating was not necessary. The sentence below may provide clarification as well. Perhaps for 3HP and less if you buy a VFD rated for single phase you are fine... perhaps only when you go beyond that and/or buy a three-single phase only VFD that there is a need to derate. I sure would given them a call though. I've had nothing but great response from them. Not the usual tech support.

"
Although Hitachi does not actually offer inverters above 3 hp specifically designed for and rated for single-phase operation, single-phase power can in fact be used with larger rating inverters, as long as care is taken to properly upsize and apply the inverter.
"

QSIMDO
01-13-2008, 07:04 PM
I have their number right here, I'll call tomorrow.
Of course, hind sight tells me I should have checked all this out BEFORE I did a ton of work to adapt the motor.
Senior moment, eh?