Operating Pfeiffer TC100 Controller

[Jackson Oswalt]

Hello all,

After months of searching, I finally managed to find a new turbo pump for a good deal. This is it:

Pfeiffer TMH 071 P

The upper bearing is magnetically levitated and the bottom bearing is oil compensated. However, since it requires such little oil, the pump comes with small "canisters" of oil that can be replaced easily.

It also came with a TC100 controller, which is the subject of this post. On eBay (which is where I got this pump) there are several listings for the exact pump. In a few of them (such as this one:https://www.ebay.com/itm/Used-Pfeiffer- ... SwcaFZEA26) the pump can be seen spinning with a few alligator clips connecting the controller to a DC supply. I've asked each of the people selling these pumps, but none of them have given me any info on how to achieve this.

Top view of controller

Side view of controller

So, does anyone have experience in operating these controllers with a couple of pin-outs as seen in the above listing? If so, please let me know what pins to connect to what in order to get it to spin up.

Thanks,
-JO

P.S. I tried my best to make the first photo vertical, but despite my efforts it kept going horizontal. Sorry.

[Andrew Seltzman]

The TC100 is an older (but nice) controller, be careful NOT to use the pinout for the TC110 controller as this will damage the TC100 controller

Here is the connection to run the controller (white is +24v, bare is ground):

a manual for your pump/controller combination is attached, pinout is on page 9 of the PDF

Pfeiffer TMH 071 Turbo Pump Manual.pdf

(434.63 KiB) Downloaded 239 times

[Jackson Oswalt]

I grounded pin 15, supplied +24v @ 4.2A to Pin 1, and connected pin 7 to pin five with is supposed to turn it on. When I switch the power on, the pump moves a little, then switches direction and then moves a little. Then it stops and the current being pulled from the supply increases as if the pump were spinning up. What am I missing? From the Pfeiffer turbo pump start-ups I've seen on YouTube, it should start accelerating after it turns itself around.

[Andrew Seltzman]

Unsure, could you send a picture of your setup?
How long did you wait after connecting the power?
How much current is being supplied from the supply while the pump is not spinning?
Does the rotor spin freely?
Try connecting 3,4 and 5 to 7 like in my picture.

[Jackson Oswalt]

I wait just a few seconds after the pump stops moving and the current begins to rise. I'm worried that leaving it could damage the pump, but maybe it just needs to pull enough current and then it'll spin up. The supply is set to 4.2A, but the controller only takes around .06. When I switch the pump on, it increases. The farthest I've let it go was to .8A. The rotor does indeed spin freely. I'll get back to you momentarily with a picture and my results with connecting pins 3,4, and 5 to pin 7. Thanks for the quick responses!

[Jackson Oswalt]

I just did another test but instead of shutting off the supply as soon as the pump stops moving, I waited a moment. A couple seconds later, the pump began to accelerate like it should. Andrew, thanks for your help once again! I finally have a working turbo!

[Jerry Biehler]

That's the typical pfeiffer start sequence. The TC600 series drives do the same thing.

[Jackson Oswalt]

I've since done a several vacuum tests with the turbo and have had disappointing results. When it's hooked up to my system, the lowest vacuum I can pull is about 50 microns. Usually, I can pull around 20-30 microns. When I turn the pump on, the gauge rises to about 65 microns and then steadily drops to about 35 microns. This is were it bottoms out. Interestingly, when I turn the turbo off the pressure immediately drops down into the 20's. Is it possible that the magnetic field coming from the turbo is messing up my gauge? Also, it's very likely I may have a leak. The pump didn't come with the venting valve pictured on page 4 of the manual: download/file.php?id=13528. In order to plug the hole I tried to use a 1/4" npt plug with Teflon tape. However, I could only screw it in a couple of mm. Also, this is the first time I have ever used an ISO flange, so there could be issues with that as well. There are no problems with the pump spinning up at all. It's incredibly smooth and makes the expected noise when spinning up.

Thanks!

[Andrew Seltzman]

It is very likely a leak.

The pfeiffer vent valve is a G1/4 thread, also known as a BSPP. These threads are designed to seal with a captive o-ring. This is a parallel thread and will not seal with an NPT, which is a taper thread as they will bind and are a different pitch. Do not attempt to thread the NPT in any further or you may damage the thread on the pump.

If you used an 1/4NPT plug, you probably screwed it into a differential pumping port (located between the turbomolecular and molecular drag stages). This port is typically only used in residual gas analyzer applications and should be plugged. The vent valve port is a smaller, G1/8, lower port on the pump.

you can buy a G1/4 plug for the differential pumping port here
https://www.mcmaster.com/#4860K126

you can buy a G1/8 plug for the vent valve port here
https://www.mcmaster.com/#4860k125

What is the best backing pressure you can obtain?
What type of pressure gauge do you have?
Send pictures of your system.

[Jackson Oswalt]

Unfortunately, living in the US usually leaves me with only npt threads. I've since purchased the correct plug. The best backing pressure I can reach is 20-30 microns. I have a Yellowjacket 69086 gauge: https://www.ebay.com/itm/Yellow-Jacket- ... xy2YtRsLuQ.