Replacing FR-SE with Hitachi L700

I'm renaming my original thread because the Hitachi (WJ-200) drive I was considering was actually not compatible, since it only has 2 outputs.

So....I ended up buying a Hitachi L700 instead. It has 5 outputs. Its still a sensorless vector drive.

The only problem I see so far is that the Hitachi outputs are open collector, or sinking outputs. The FR-SE outputs are sourcing. The control will be expecting 24v for an active signal (1)...... but, the Hitachi will be outputting a 24v signal from the internal pullup, then sink to 0 when active (1). This is backwards.

It looks like I will need to use a relay to invert the outputs. I have a bunch of extra ice cube locations on my relay board, so I guess I will run them over to there.

Nothing is really that time sensitive that a little delay from an added relay will affect. (I think)

The inputs on the Hitachi are configurable to either source or sink.....so there shouldn't be an issue there.

Drive should be here by Thursday, so I have some time to get the FR-SE pulled out.

I haven't decided, yet......but I may just use the base part of the FR-SE as a mount since the contactor, CB-1 shutoff, and all the wires are already to length for its configuration.

I'll try to keep posting progress pictures and text of what I'm doing......although it's not one of my strong points. I often get too wrapped up in things to remember to take pictures until its too late. I will try, though.

Mike

I pulled the old drive today......I cannot believe how heavy that thing was.

With the drive out, I tested the drive ready normal output which was on pin 18 of CON1. I put 24v to the pin, as the drive output would, and was able to clear the NMI 20 alarm.

That's a good sign so far.

Mike

Got the tracking info for my L700 I ordered yesterday.

They used the wrong zip code, and didn't bother to see that it changed the destination from Montrose, CO to Carrol,IA, too.

Looks like that is going to add some ship time since its already left Dallas. They said its no problem, because they can "intercept" and reroute it. Ya, I'm sure the UPS semi driver is probably pulled over somewhere and is sifting through his load to find my mislabeled package.......lol. I'm just gonna figure on next week, now.

Nice.

I drew a picture of the schematic that I'm going to use for the outputs.

It may or may not be helpful to anyone else......I'll post it anyway.

I ordered some more Omron 24v relays, and intend to just put them in the extra holes on the relay board mounted to the cabinet door and wire them from there.

The new drive is about the rectangular dimensions of a sheet of paper.....but just a little thicker at 6.9". It weighs about 12lbs.....lol.

I really hope I can make this thing work right.

Mike

michaelthomas said:

I pulled the old drive today......I cannot believe how heavy that thing was.

Click to expand...

Why was it so heavy? Replacing a heavy part with a 12lb part seems like apples to oranges and something important might be overlooked.

Then again, new inverter welders are a fraction of the weight of the old transformer welders and they work great.

Would a new(er) Mitsubishi drive be easier to retrofit in place of the FR-SE instead of the Hitachi?

We are eagerly watching your progress, Mike, as someday, we might be following in your footsteps.

Phil.....as you suspected, I believe its the advance in technology that has made the new drives so much smaller and lighter. Kinda like comparing a 80's television set to a modern day flat screen, I guess.

This Hitachi drive is not a closed loop drive like the FR-SE. The PLG on the MITS is the "encoder" that closes the drive loop. It's not the encoder that is attached to the spindle.

The Hitachi is a sensorless vector drive. It may, theoretically, not be able to hold a set speed as well as the Mits...... but it should be more than adequate for a lathe. There's a ton of lathes that run sensorless vector drives. The closed loop system can allow you to run lower rpms with full torque, but the vector will easily run full torque down to a couple hundred rpm and probably lower......and then with low gear, that will get you another 3 times lower or so. I would expect this drive to be able to deliver full torque down to 75 spindle rpm.....maybe lower.

On first impression, if the spindle speed varied a bit.....you might expect threading to be a problem. It shouldn't be, though. The Z axis is electronically "geared" to the spindle rpm through the control (which is monitored by the encoder on the spindle itself) during threading. If the spindle were to slow down, the z axis will slow down accordingly in lock step along with it......at least that's how it works on every other control that I have used. The nice part is that with a 20hp motor, the minimal depth of cut in a threading operation is less likely to bog the motor, anyway.

I don't know if a newer Mitsubishi would be easier. I would guess that it wouldn't be.

I really hope that no one will need to follow these footsteps.....lol.

Mike

"Why was it so heavy? Replacing a heavy part with a 12lb part seems like apples to oranges and something important might be overlooked."

a modern mits drive is about a forth (or less) the weight of those old FR's

but
they do have there heat sink outside the cabinet
i might be tempted to use the old heat tube setup from the fr unit to help keep the heat down on the new device

I was considering that myself.....I'm definitely running the braking resistors outside the cabinet.

I've been scouring the electrical manual trying to determine what turns on the contactor directly after CB-1.....and even what that contactor is named.

I see CB-2, which looks like it would be right....but that refers to another "no fuse breaker" like CB-1 (the 100 amp breaker).

Next to CB-2 in the manual is this......(0712).....does anyone know what this number references?

I was thinking the OLR relay was what makes this contactor pull in.

There is also a 53---[ ]---103.....which I am thinking may refer to the wires on the contact. This is on page 401 2/2.

Any ideas here?

Mike

i've done a couple of updates from fr-se and fr-sf drives to modern mits MDS drives. i hope you get this to work it will be alot cheaper. only problem i could see is if the drive is not holding speed accuratly engought you could split lead when threading. also the if could get speed mismatch alarm if commanded rpm doesn't match what the spindle encoder is seeing. hopefully all this will be cleared up next week and you are running with no problems

Justin,

I don't see any speed mismatch alarm listed in my manual......do you have an alarm number for that?

I don't see where the PLG does any communication with the spindle encoder, either. As far as I know, the FX-53 does the digital to analog speed reference conversion.....which I believe is just a scalar of the max speed. The only real reason that I know of for true closed loop feedback (PLG) is to extend the motors' max torque range down to almost zero rpm.....and to provide reliable speed regulation at those very low motor rpm's.

There are only a handful of outputs from the FR-SE back to the control.....and none look capable of relaying a digital or even an analog signal that would do equality comparison between the PLG and the spindle encoder. From what I see, the PLG only talks to the FR-SE, and the FR-SE is the only communication link back to the control.

There is an output from the spindle drive that just notifies the control that the spindle is up to its commanded speed, but that is a settable output that I will have on the Hitachi as well.

I don't know.....but it looks like I'm gonna find out.

All of my hopes are based on what I see on paper right now.....It will be interesting to find out what I don't see, and what reality has in store for me next week.

I'm gonna keep praying.

Mike

I went to the shop to look at the contactor again, and noticed it has a 240v ac coil.

I also found CB-2 in the cabinet up top.....so clearly the contactor is not CB-2.

Since its 240ac.....the control must not have anything to do with operating it, and neither does relay OLR.

I'm wondering what the heck that contactor does? The only 200-240 is coming off the main transformer and then right to CB-1 (100A for spindle)and CB-2 (30A for Hydraulic, Coolant, and Chip Conveyor).

Maybe the FR-SE manual has something about it?

Mike

" ......(0712)....."

possibly page xx7 line 12 (the sheets will usualy all be something like 407 or 408 the 7 would mean page 407

you are a mile over my head on this stuff but that big contactor in the spindle drive may come on with machine ready.

i should have a mits FR-SE book if you think it would help

Kevinsr......I think you are exactly right about the (0712) being a reference to page and row. I wish they had a manual that told you how to read the manual.

Every so often I'm struck with panic and feel that I may be over my head, too.....lol.

I also thought that the contact may be pulled in with the machine ready (OLR) relay, but I don't see any 240 AC coming off the (OLR) which would be needed to activate the coil on the contactor. Its a mystery to me right now. ???????

I have been referencing the FR-SE with a PDF that I got online.....it's not as nice as a book, but I'm hoping (really hoping) that I won't need the FR-SE info ever again. Thanks for the offer, though.

I found he contactor in the FR-SE manual. Its called MC-1. Its used primarily as a function of the fault sequences the FR-SE puts out. Any kind of fault will drop the contact.

I don't really think I need it with the new drive.....but I'm certainly open to hear arguments about why I do.

The Hitachi shuts itself down due to any triggered faults, and I think the contactor would be redundant since you must manually reset the drive once it has been tripped.

Once the drive trips.....the ready output signal is also disconnected from the control, which will force a NMI 20 Emergency. So that also provides a bit of redundancy.

Unless someone can convince me otherwise....I'm not going to bother with the contactor on the retrofit.

Mike

This is a guess, but my guess is a true OSHA-style safety circuit requires a VFD to simply go "zero input power" instead of simply causing the stop signal to be triggered.

I think a VFD isn't a fail...(to)....safe device so that's why...in other words there is some sort of failure mode where the stop circuit can't tell the drive to stop.

So then its up to another device to open up the incoming L1/L2/L3 and a contactor is nominated for this duty.

For example if you throw open the door in the middle of a program and stick your head in there...the VFD needs to go to zero power.

Also for example for lockout/maintenance purposes, if the safety circuit causes drive to go zero power, it can't hurt anyone by being started accidentally

I'm very interested in this, have helped integrate a couple VFDs on much simpler manual machines, but its all about understanding the inputs and outputs and then programming the new device. New(er) VFDs are normally loaded with a lot of bells and whistles not normally needed but now may be the time to appreciate some of them...

Matt.....I see what you are getting at.

I can use the drive faults to output a signal that will drop the contact......but for the life of me, I can't think of a good way to latch the contact to begin with. You have any ideas on that? The original must be on a timer circuit in the ladder that would act like a momentary push button until the drive could take over with a ready signal to hold the contact.

I realized today that there is an electric blower motor within the spindle motor for cooling. I don't know if its a supplement to a shaft driven fan.....or if its the one and only. I really hope its not the only cooling fan.....that would seem really dumb. I suspect its in addition to a normal shaft fan, but I wonder if anyone out there can confirm or deny this?

I would think that a shaft driven fan would be insufficient at low motor rpm, and an electric fan would be less than optimal at higher speed.

Mike

"a shaft driven fan would be insufficient at low motor rpm"

i belive the only fan is the one driven by that little 200volt three pase circuit coming out of spindle controller
it is mounted where a shaft fan would be on the end of servo.
you could pick up the needed voltage off any one of the other " allways on" contactors like the hyd
or just drop a little starter in for it that comes up at NC on

Hi Kevinsr......thanks for the response.

My fan motor only has 2 wires.....could it be single phase?

Mike

Is there anyone who could put a voltmeter across MS1 and MS2 leads to the fan motor on the spindle. They are 2 small leads that are zip tied to the motor leads from the FR-SE.

I'd really appreciate it.

Mike

it is a single phase "cheat" driving that fan
i can check it with a meter later to confirm

My notes show the spindle motor fan for the QT10 I worked on is ~ 220 V. I can't remember if it's driven from 208 V (3 phase line-to-line) or some other voltage.

It's kind of an odd size and for some reason the fan blade/rotors get damaged easily. I found a local replacement that bolts right in but it's on its 2nd rotor. Both the original fan and the replacements are plastic. I added a cover to keep oil and chips off the rotor but the new one is starting to make noises. I'm thinking of putting a metal bladed unit in there but the largest one I've found is physically smaller even though it moves almost the same amount of air.

If memory serves, the FR/SE has some sort of contactor/circuit breaker for protection and can be tripped by all sorts of conditions. Most of what it does is built into the new drive itself and should be pretty much hidden from the control.

I was thinking about how difficult it might be to retrofit a new drive but when looking at it now, it looks much simpler. The FR-SE uses older, less efficient technology and that makes it so much bigger. One thing it does is regenerate energy back to the power line when decelerating. It may not be a big deal but I'd recomend at least making provisions to add a braking resistor just in case the spindle takes too long to slow down.

Cheers,

Duane