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... or a circuit to accomplish the same thing.
Situation: Switching on 110VAC, need to turn on a 5VDC source for NO MORE
than 1 sec about 50ms after the AC power is flowing.
Any inexpensive solutions?
Thanks,
-nef
Forgive my lack of knowledge.. I know what each of the components functionsPut the relay in series with a capacitor and resistor, driven through
a diode? Also a small cap across the relay to give 50mS?
then you should not. It could be very dangerous for you. We areStepan Novotill <snovotill@hotmail.com> wrote in
news:e9idlv4cd9bgq70gmhekhu7vh3nd0un2ef@4ax.com:
Put the relay in series with a capacitor and resistor, driven through
a diode? Also a small cap across the relay to give 50mS?
Forgive my lack of knowledge.. I know what each of the components functions
are, but sizing etc I'll be lost on. Any chance of an ASCII schematic? ;-)
Thanks!
-nef
I don't mean to be harsh, but if you are not able to put that together
OK, here is the ASCII schematic, but only to look at:I don't mean to be harsh, but if you are not able to put that together
then you should not. It could be very dangerous for you. We are
talking about lethal DC voltages from half-wave rectified AC.
Why not start with some safer projects using batteries.
Please accept my apologies.
No, it won't close again at power-off.What am i thinking?On Sat, 13 Sep 2003 05:31:12 GMT, Stepan Novotill
snovotill@hotmail.com> wrote:
I don't mean to be harsh, but if you are not able to put that together
then you should not. It could be very dangerous for you. We are
talking about lethal DC voltages from half-wave rectified AC.
Why not start with some safer projects using batteries.
Please accept my apologies.
OK, here is the ASCII schematic, but only to look at:
Line--R-+-Cbig-+-|>|---+---||||||---+---Line
| | | |
+-100K-+ +---Csmall_--+
Note: relay may close again upon power-off
It is a crappy circuit but may be good enough.
The cap and resistor values depend on your relay.
I'd use a 5 watt resistor for R and a photoflash cap for Cbig
Relay is 220VAC or 120VAC.
The diode is 1n4007. The circuit needs time to bleed off capacitor
charges between invocations.
MUCH safer to do this in low voltage DC. DC is easier to design but
much more complicated circuit.
Oh yes, and the caps may EXPLODE if you put them in backwards.On Sat, 13 Sep 2003 05:48:43 GMT, Stepan Novotill
snovotill@hotmail.com> wrote:
On Sat, 13 Sep 2003 05:31:12 GMT, Stepan Novotill
snovotill@hotmail.com> wrote:
I don't mean to be harsh, but if you are not able to put that together
then you should not. It could be very dangerous for you. We are
talking about lethal DC voltages from half-wave rectified AC.
Why not start with some safer projects using batteries.
Please accept my apologies.
OK, here is the ASCII schematic, but only to look at:
Line--R-+-Cbig-+-|>|---+---||||||---+---Line
| | | |
+-100K-+ +---Csmall_--+
Note: relay may close again upon power-off
It is a crappy circuit but may be good enough.
The cap and resistor values depend on your relay.
I'd use a 5 watt resistor for R and a photoflash cap for Cbig
Relay is 220VAC or 120VAC.
The diode is 1n4007. The circuit needs time to bleed off capacitor
charges between invocations.
MUCH safer to do this in low voltage DC. DC is easier to design but
much more complicated circuit.
No, it won't close again at power-off.What am i thinking?
No need to apologize, but I think putting in three phase circuits andOn Fri, 12 Sep 2003 23:48:13 GMT, nefarious
sfdkjshfskjhflkhj@erkjdfkjhlkhsdkfjhsfj.com> wrote:
I don't mean to be harsh, but if you are not able to put that together
then you should not. It could be very dangerous for you. We are
talking about lethal DC voltages from half-wave rectified AC.
Why not start with some safer projects using batteries.
Please accept my apologies.