Film-Tech Forum ARCHIVE: Strong Microswitch vs Carbon switch on platters

This is topic Strong Microswitch vs Carbon switch on platters in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Stephen Frazza (Member # 2320) on 01-23-2005, 06:37 PM:

I have 7 strong platters where i'm at and they all have microswitches except for maybe 3 decks.Those have carbon switches.The carbon switches seem to pay out a little smoother then the microswitches.Not so jerky stop-starty.

So I have a box with 10 carbon switches that have been in the booth since before I started.I'm not sure why they were taken off in the first place and I was thinking about putting them on next time I switch out a microswitch.

My questions are;
If a carbon switch goes what goes in it?
Is there a way to test one out other than putting it on a platter and running it?
In your opinion should I change or just stay with the micros?

Posted by Mark Gulbrandsen (Member # 72) on 01-23-2005, 07:19 PM:

The carbon switch(or pile) works by compressing a stacked pile of carbon disks in an insulating tube. The more they are compressed the more voltage they pass... sort of like a pressure controled valve. What fails is the carbon disks themselves, eventually they arc, resistance can go up and then they don't conduct very well and can give erratic control.

Both carbon piles and the phase control switch suck big time. They are very dependent on actual platter timming to work correctly and good luck holding decent timming on any of those platters for more than a couple hours. What you should try is the very light tension microswitch thats available from alot of dealers out there. It will give much better performance than the standard micro that comes on the platter. There was a thread about those micros but I was unable to turn it ip via the search engine... perhaps Joe will come to the rescue on that......

Mark

Posted by Steven J Hart (Member # 2340) on 01-24-2005, 07:37 AM:

The start-stop motion of the payout platter caused by the micro switches may not be pleasing to the eye, but it works! Reliability is the name of the game. The micro switches fail much less frequently than the carbon stacks.

Posted by Stephen Frazza (Member # 2320) on 01-24-2005, 10:36 AM:

quote: Steven J Hart
Reliability is the name of the game

Yeah, I should have mentioned that my main reason for wanted to change was reliability. I always have in the back of my mind "is this the day a microswitch is going to decide to die on me"

But for some reason I was thinking the carbon switches were more reliable.Maybe cause of the few we have I've never had to touch them.

Posted by Ken Layton (Member # 133) on 01-24-2005, 10:43 AM:

Those carbon switches were always failing suddenly or becoming erratic. Wait till you price a replacement carbon switch. [Eek!]