On 1/20/2015 2:12 PM, whit3rd wrote:
On Monday, January 19, 2015 at 8:10:24 PM UTC-8, DoN. Nichols wrote:
On 2015-01-19, Cydrome Leader wrote:
Neon John wrote:
On Fri, 16 Jan 2015 17:59:45 +0000 (UTC), Cydrome Leader
wrote:

There should be a A, B and C legs, but how is this order determined by
testing?

Here's how to build a very simple one:

http://webspace.webring.com/people/gl/lemagicien/elecpage/3phase/3phase.html

That 'schematic' shows lamps, but the thing WILL blow up if you put a simple neon
lamp in those positions: you need to use neon lamps plus current-limit resistors,
and the circuit works because of the high strike voltage and lower sustain voltage
of the neon lamps (can't do this with LEDs!).
It looks like the first lamp to fire causes the capacitor offset voltage to shift,
so the second lamp is dimmer. It isn't polarity-sensitive, the lamps will flash
twice per cycle.

The doc lists incandescent - 220v lamps. Baring them, put two 120v
lamps in series and it should work just the same. Light is spread over
four bulbs...

Martin

On 1/20/2015 7:57 PM, whit3rd wrote:
On Tuesday, January 20, 2015 at 1:46:26 PM UTC-8, Bob Engelhardt wrote:
On 1/20/2015 3:12 PM, whit3rd wrote:

That 'schematic' shows lamps, but the thing WILL blow up if you put a simple neon
lamp in those positions: ...

Actually, that circuit is for INCANDESCENT lamps.

Yep, I missed that. It relies on lamp resistance value as well as incandescence,
which is an odd combination. Hot lamps are much higher resistance than cold ones.
I'd guess a neon-plus-resistor would allow more voltage range, and you could keep
a single capacitor value

The issue with neon in this example is voltage drop. Xc of the
capacitor is vs the resistance of the lamp.

A neon is a switch. It is a voltage regulator. It fires at a defined
voltage and turns off at another. One can't see a dim one unless you
limit the current and keep the voltage constant. An FET would have to
be used....

Use lamps. Not neon glow tubes.

Martin