[captainkaos]

We have four Leadwell mills. An MCV-OP, two V-40's, and a brand new, just powered up today, V-20.

The V-20 and the newer V-40 (2014) both have SV0438 (Z) INV. ABNORMAL CURRENT alarms when we rapid Z up at 100% as in tool changes.
They work fine at 75%.

I think I know why, but I'd like opinions.

Last year, we moved into a new shop. The power is 208 - 120. Our old shop had 240 -120 and a wild leg. The 2014 V-40 ran fine there, and here until air conditioning season started.

I suspect I'll need to install buck / boost transformers at our supply panel.

Any thoughts?

Thanks.....Rob.

[engnerdan]

We have four Leadwell mills. An MCV-OP, two V-40's, and a brand new, just powered up today, V-20.

The V-20 and the newer V-40 (2014) both have SV0438 (Z) INV. ABNORMAL CURRENT alarms when we rapid Z up at 100% as in tool changes.
They work fine at 75%.

I think I know why, but I'd like opinions.

Last year, we moved into a new shop. The power is 208 - 120. Our old shop had 240 -120 and a wild leg. The 2014 V-40 ran fine there, and here until air conditioning season started.

I suspect I'll need to install buck / boost transformers at our supply panel.

Any thoughts?

Thanks.....Rob.

I would suspect a supply voltage issue, an under voltage condition would make the motors work harder to generate the same power output as they would at a higher voltage. I would check the machines and see what they are actually rated for and make sure that is what you are feeding them. If the name plate gives you a voltage range then there is typically a voltage adjustment transformer built into the machine. I know Haas machines and Mazaks usually have them but I have never been in a Leadwell.

-Dan

[captainkaos]

Thanks, Dan. That's what I think too.
We had the power company out and everything is within spec. The lowest voltage we read was 207 at the drive power supply.
Its rated input is 200 to 240 but the guys setting up the new V-20 said if it hits 205, there is trouble.
That's a bit too close for me.
They have taped transformers, but only for the control voltage, contactor coils and such. The servo / spindle supply has no adjustments.
I just scored some buck / boost transformers that I'll install at the breaker box.
They should bring the voltage up to to about 230.

By the way, these machines are FAST. We were running the same parts on one of our Kitamura HX 300's and the Leadwell made them almost twice as fast even
with the Kita making four parts per pallet and the V-40 two per load.
I'll let you know......Rob

[drdos]

I just ran across this exact same problem. Customer had a machine for 17 years and moved it to their other plant just down the road from where they were. However we found that the place it was moved from had 208V and was a Wye power configuration. The new shop had 240 Delta. Fanuc drive really need the Wye. The way you tell is measure your incoming voltage phase to ground. Delta will have one leg higher than the other two. The Wye will be balanced between all phases to ground. The drives are rated at 200 to 230 volts as long as you are in that range you ought to be OK. As long as you are feeding them with a Wye isolation transformer.

[BIRDTOOL]

Funny this thread started as we have a 3yr old Leadwell 40it that just started getting the same alarm 2/3 weeks ago. We were running mold cavities that required a lot of drilling and had the rapid at 100%. We turned it down to 75% and no longer had issues, (it also made ZERO difference in the program run time??).

We first thought incoming power but it checked ok; next we swapped out the servo drive and that made no difference.Thought maybe it was getting too hot so opened the panel door and had a fan on it (the shop is air conditioned too), no luck.

Turns out the machine has got a "duty cycle"(the spindle does, check your manual), the installed Fanuc hw is just not rated to do what the machine is "advertised" to do (100% of the time). Our only thought as to why turning the rapid to 75% made no time dif is since the hw is "underrated" it cannot accelerate faser to get from point a to b at 75 or 100%, it tries to by dumping more power but that just turns into thermal energy in the drive.

We've also replaced all the "D"s on the machine labels to "K"s, seems more appropriate.

In the end, what you pay for these machines you do get value for the dollar, and we can't beat our service when we do have issues.

[captainkaos]

@drdos- We have a Y connection here. 120 V to neutral on all legs. The old shop had Delta with a wild leg, but the machines didn't whine about it. I guess we just got lucky.

@BIRDTOOL- YES!!!! This is the information I was looking for.

I installed buck / boost transformers at the panel for the problem V-40 last night and got 230 volts line to line. I ran Z through several rapid moves at 100% with no problems, but this morning as soon as we tried to run a part, it alarmed out again.

Parameter 1420 sets the rapid feed rate and I think I'm going to cut it back until the alarm goes away. That should make it a bit more "operator proof" and save me some weekend trips to the shop.

[captainkaos]

P.S.
Our 2008 V-40 has the same drives and power supply as the 2014 version, but the servo drives are connected to the PS by a few feet of 14mm wire as opposed to the newer machines direct buss.
I suspect there is just enough resistance in the wire to keep the current under the alarm threshold in the older machine.