PAM clock question...

[pinballdude]

Anyone know why these old clocks sometimes start running BACKWARDS? This seems to happen when the power goes off for a few seconds.
Thanks.

[halehouse]

Good question. Mine does that too. I don't know why.

[Kilroy]

The pam clock motors are bi-directional. depends how it's getting hit with current

[Eric]

I was told by a good source if you turn the plug around and it should run the right way...

[addamb]

Alot of older clocks have a "reversing" gear that basically looks like a little gear with curved teeth. It's typically the first gear that the main motor gear hits before all the others. They are supposed to curve to the right if you are looking head on at the gear. I have 1980s Dr Pepper "prism" clock that had this issue, and it turned out at some point someone had dissassembled the gears to clean them and flipped the reversing gear over. It was an easy fix once i realized what i was working with.

Here's a link that helped me. Different motor, same idea though, read the top paragraph where it talks about it.   https://www.norkro.com/webpages/lanshireinstructions.htm


P.S. Unless you flip the armature (Which has to be deliberatly done), AC motors don't care which wire is where (I.E. flipping the plug will have no effect on teh direction), they will spin the same direction reguardless.

[Larry]

That's funny about it running backwards when the plug is reversed because when I was at my first job I reversed the plug on a wall clock and it ran in reverse too.  Later on when I new a little about ac voltage I was thinking about that clock and was wondering why it did that. The mystery continues. 

[addamb]

That's funny about it running backwards when the plug is reversed because when I was at my first job I reversed the plug on a wall clock and it ran in reverse too.  Later on when I new a little about ac voltage I was thinking about that clock and was wondering why it did that. The mystery continues.  

When the reversing gear goes bad, or is missing in clocks that need one (the one i talked about in my above post) you get a 50/50 chance on which way the motor spins when you plug it in, that's why that gear is there. It's not dependant on the polarity of the wires or plug, but without that gear it's just a matter of which way the motor "feels" like spinning when pulgged in that time. It may spin clockwise 10 times in a row, then one time you plug it in and it spins counterclockwise. The reversing gear makes sure if eventually ends up spinning clockwise, usually within a second or so of plugging in. If you don't have a second hand, you will never even know this is happeneing behind the scenes.

[halehouse]

Yep. If it is running backwards after a power outage, I just unplug and plug it in until it runs the right way.

[Chedki]

Yep. If it is running backwards after a power outage, I just unplug and plug it in until it runs the right way.

Yeah, that's what I've always done with my PAM clocks too.