Old, Used Siemens MasterDrives

Mad_Poet

Member
Join Date
Feb 2017
Location
Virginia
Posts
375
Dear Sirs,
My boss got me some old used 'somebody else's spare' MasterDrives
to stow as spares for our machines. Some are tagged as 'will communicate
but will not run'.

The part number on our drives is 6SE7021-OEP50-Z and that is followed
by another line Z = G91 + G42 + C43 + F01 + F29. (We do use the F01 option
in our machines and a drive will not work for us without it.)

The drives the boss got me have a part number of 6SE7021-0EP50. (No Z).
And no second line of stuff.

Question 1. is there a quick idea of what the Z = stuff is? (I'm guessing
it is the three cards and the F01 option.) Both my existing drives and the
the 'strange' drives have three cards in them and (at least in one of the
strange drives) DriveMonitor tells me the cards are the same in mine and
the stranger.

Question 2. The firmware version number in my drives is 1.5.5 and the
firmware version of the strangers seems to be 1.5.1. Assuming the cards
and that F01 option are all there and the same, should this drive work in
my machines?

Question 3. Parameter 978. When Technology option F01 is active
it should be '1'. My drives are all '1' and it looks like the strange
drives are also set to '1'. Can I safely assume this means the F01
option is there and active?

Poet.
 
Before you waste any more time on them, determine how long they have been off line (un-powered). If more than a year sing being energized, the capacitors need to be reformed PRIOR to having ANY connection to the line. If someone powered them up, even unloaded, after being on the shelf for years, they may not be worth using, the caps have likely been damaged.
 
Thank you, JRW.
I very much appreciate this.
Just for giggles, a while back my Boss 'acquired' a drive - and it was version 1.6.
I was desperate to get my machine running and when I tried loading my 'version 1.5'
program into it, it complained then did the conversion and it ran OK for me.

And, JRAEF, I am aware of the need to re-form the capacitors in the drives before
trying to run them. We have a rig set up on the wall just for that purpose. And, I
put one of the 'strange' drives up on it last night before I went home.

Short of actually putting one in the machine (pain in the rump) is there a way to
check that the capacitors are OK before trying to install it?

And, lastly, a horror story. (I'm wondering if anyone else knows of such a thing happening.) A couple of years ago now I had the DC rectifier unit go bad and it
ate two 7.5 KW MasterDrives. Then it ate one of my two spares before I figured
out what was going on. (That was when the Boss got me a version 1.6 to try.
Got the machine running with it.)
Poet.
 
The Rectifier damage might be related to your power system. Most drives, especially those designed outside of North America, REQUIRE that the line power be from a solidly grounded Wye system. But here in NA, we sometimes use Delta systems or High Resistance Grounded (HRG) Wye systems. If that’s the case, many drives give you some instructions on removing a ground reference point for the surge protective devices (MOVs or SIOVs) in the rectifier and any noise filtering components. Some mfrs make those ground reference points easy to remove, Siemens does not, you must disassemble the front-end of the drive to get to it. Also, the manual that came with Master Drives doesn’t make that issue clear, they issued a supplement for North America explaining it, but that usually gets lost on used drives and if you don’t know to look for it, it’s hard to find after the fact.

So what happens if you don’t remove that ground reference is that the first time there is a ground fault anywhere else on the system, the MOVs and filter components in the drive that are referenced to ground attemp, very very briefly, to make your HRG or Delta system into a grounded Wye, until those components vaporize and spew their conductive guts all around the rectifier, causing everything to short and fry.

As to detecting if caps need reforming, I know of no proven way to do it. I heard someone say they could detect it by looking at the Series Resistance of the caps, but you would need to have known what it WAS to see the difference, and that’s not something you can get from specifications b
 
Last edited:
I love horror stories . . . Except for when they happen to me.

I had noticed that when I was re-forming one of the drives of dubious parentage the cards had lights blinking and the PMU came up. And I was able to attach the laptop to the drive and access it. This is nice I thought.

Wanting to further test this drive, I tried hooking a generic three phase motor to it. 480 VAC to it. And a dynamic braking resistor. Started it up, PMU and lights good. Accessed it with the laptop and dumped a 'factory defaults' into it then I went through the factory commissioning screen and tried to set it up to run the motor. (No encoder.) I could not get it to run.

So I decided I'd try another drive. Not thinking about it, the drive I grabbed had not had its capacitors reformed. Plugged it all up, 480 VAC and all. No lights, nothing. Then I remembered I needed to re-form it so I unplugged everything and plugged it into the reforming rig . . . . A minute later the 150 watt resistor blew and stunk up the shop.
(I think I had blown the caps out of the drive.)

So I tried a third drive from the 'dubious parentage' pile - this time putting it on the (repaired) re-forming rig for several hours first. Still no PMU and no lights.

I attached an external 24 Vdc supply and was able to access the drive. Reloaded the new program into it. Everything looks OK with it but I still can not make the motor run. I think it was a status word said 'drive disabled' and I don't know what I'm missing.

Question 1. Why does that one MasterDrive light up the LED's and the PMU when the reforming volts are put to it or straight 480 VAC is put to it - but the other drives do not light up.

Question 2. Any suggestions as to what I might have to do to make the motor run? It is just a generic three phase motor with no encoder. (And yes, I know about the bottom of the drive monitor panel and its start / stop buttons. No joy there.)
Poet.
 

Similar Topics

Hi all, I'm hoping someone out there may have had experience with an MCGS branded HMI. This company is based out of China and makes a fairly...
Replies
19
Views
14,105
Hello Guys, Newbie in TIA Portal and Siemens here. Now I have an old project which i have downloaded online. This is the Color Mixing project...
Replies
4
Views
10,726
Don't want to cause any offence by this request. I am looking for an old Mitsubishi FX style (brick) PLC for training purposes. An old one...
Replies
0
Views
5,393
Hey all, I am currently working on a depalletizer for a customer and we are doing a hoist upgrade. This is a SLC500 processor and the drives are...
Replies
6
Views
186
Hi, One of my customers has an old fabric tensile testing machine. The IC # AD7501KN of its controller has malfunctioned. This IC is related to...
Replies
1
Views
62
Back
Top Bottom