On Sat, 16 Apr 2011 22:50:29 +0100, T i m wrote:

Hi all,

I would like to use a uniselector (got) to step to its next position
upon connection to a mains supply (through 'X' circuitry). This will
probably be at one_per_day time intervals.

Ideally said circuitry would consume as little energy itself as
possible.

What I'm actually trying to do is 'cycle' an intelligent low current
(.5A) but quite expensive charger to a range of smallish 12V lead acid
batteries. Once each battery is actually charged (probably elsewhere)
it will be kept topped up by said project applying said charger once
every Y days (where Y could be 25 as I think it's a 25 way selector).

I could use (make) a 240 ac to 50V DC PSU (assuming the uniselector
was designed to run at that) and then create a suitably long one shot
pulse on power-up (charge cap?). I could probably even just use one
mains digital time switch, energising the uniselector 'step' cct for
one minute, again via a suitable charge cap (so the coil isn't left
energised for longer than needed)?

Ideally though both the charger and the stepper sides would be power
cycled at the same time (to ensure the charger was reset). Or the
charger de-powered when the selector is pulsed (so the selector isn't
actually switching the charge current).

Ideas welcome please. ;-)

Cheers, T i m


Sounds like a great application for a stepping relay. Typical specs: 10,
20, 25, 40, 50, and up to 100 steps; 2 to 10 poles; 250 V, 2 A.

Next; trying to find one.

New ones can be had, but are spendy:
http://www.surplussales.com/switches/SWLedex-1.html