Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

SMTnet
»
Electronics Forum
»
Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor?

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor?

Subscribe to Thread

I'm looking for advice, please, concerning PSB ’s. I’m a com... - Aug 06, 2015 by Richard

If the pendulum is motor driven, it's more likely that a cap... - Aug 10, 2015 by robgd3

Thanks for your reply, Rob. I wish I could attach images he... - Aug 10, 2015 by Richard

I'm no clock expert, but, even that unit you linked appears ... - Aug 11, 2015 by robgd3

Thanks, Rob... when it says on that eBay mechanism that it's... - Aug 11, 2015 by Richard

Richard

#74339

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor? | 6 August, 2015

I'm looking for advice, please, concerning PSB ’s. I’m a complete newbie and not very technically minded, sorry!

I manufacture and sell wall clocks that have a swinging pendulum. The pendulum mechanisms are made overseas and designed for the pendulum to swing approximately 60 times per minute.

I would like to slow down that swing to approximately 30 or even 20 swings per minute.

In the attachment are photos of the pendulum mechanism (which fits on the back of the wall clock), showing the PCB, and capacitor. (The capacitor has on it: 47uf16v)

(SORRY, I CAN'T SEEM TO ATTACH PHOTOS TO THIS POST)

Could you advise, please, on what's involved in slowing down the pendulum swing? Is it a simple case of installing a resistor, or different size capacitor?

Can these PCB's be adapted to swing slower?

I have 1000 of them that need to run slower, instead of at the 60 per minute.

Many thanks,

Richard

reply »

robgd3

#74356

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor? | 10 August, 2015

If the pendulum is motor driven, it's more likely that a capacitor change will accomplish what you want than a resistor change.

You've got a 47uF in there...try a factor of 10, and put a 4.7uF in there and see what happens.

If the pendulum period is driven by the weight/length of the pendulum (sort of the whole point of a pendulum), then it might not matter what you do to the motor mechanism. The mechanism might just be for initializing the system, and adding energy back into the system when it starts to slow down, rather than establishing the period of the pendulum swing.

cheers, ..rob

reply »

Richard

#74358

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor? | 10 August, 2015

Thanks for your reply, Rob. I wish I could attach images here, but despite the option for 'attachments,' it won't let me attach.

The pendulum mechanisms are the cheap plastic type, from China, not the older style mechanical ones.

Not sure if this link works, but it may show the type I'm dealing with, and trying to slow down:

http://www.ebay.com/itm/New-Takane-Pendulum-Clock-Kit-Quartz-Clock-Movement-130A-w-hanger-w-hands-USA-/181076717808

Many thanks, Richard

reply »

robgd3

#74363

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor? | 11 August, 2015

I'm no clock expert, but, even that unit you linked appears to have the period set by the weight on the pendulum. That unit notes that the pendulum is adjustable....though, I'm not sure how/what is adjustable...I would expect it to be the weight.

If the one you're working with has the weight adjustable...I'd try moving it up/down the shaft of the pendulum, and seeing if that affects the period. If it doesn't, then I'd give the capacitor change a try.

cheers, ..rob

reply »

Richard

#74365

Advice for a newbie, please: Can an existing PSB be adapted to slow it down? Maybe add a resistor? | 11 August, 2015

Thanks, Rob... when it says on that eBay mechanism that it's "adjustable," it's the length... it's scored in increments, to snap off at the required length.

So no help with this issue, unfortunately.

reply »