Detecting 110 AC
Archiver
Posts: 46,084
I have a little project where I need to count the number of times a
liquid level sensor activates. The sensor shuts off a 110 solinoid,
so all I need to do is check for voltage and increment a counter.
Whats a simple way to sense the voltage that would provide isolation?
I was thinking I could just wrap a wire around the hot and check it
for voltage - inductive type thing.
Any other simple methods folks use?
liquid level sensor activates. The sensor shuts off a 110 solinoid,
so all I need to do is check for voltage and increment a counter.
Whats a simple way to sense the voltage that would provide isolation?
I was thinking I could just wrap a wire around the hot and check it
for voltage - inductive type thing.
Any other simple methods folks use?
Comments
>I have a little project where I need to count the number of times a
>liquid level sensor activates. The sensor shuts off a 110 solinoid,
>so all I need to do is check for voltage and increment a counter.
>
>Whats a simple way to sense the voltage that would provide isolation?
>I was thinking I could just wrap a wire around the hot and check it
>for voltage - inductive type thing.
>
>Any other simple methods folks use?
How about a small relay activated in parallel with the solenoid coil. A
set of contacts could switch either a logic high or logic low, your choice,
to a Stamp pin. This also gives you isolation from 110 VAC as well as the
inductive spike from the solenoid. The relay coil must have a suitable
duty cycle.
Jim H
--- "ghidera2000 <ghidera2000@y...>"
<ghidera2000@y...> wrote:
> I have a little project where I need to count the
> number of times a
> liquid level sensor activates. The sensor shuts off
> a 110 solinoid,
> so all I need to do is check for voltage and
> increment a counter.
>
> Whats a simple way to sense the voltage that would
> provide isolation?
> I was thinking I could just wrap a wire around the
> hot and check it
> for voltage - inductive type thing.
>
> Any other simple methods folks use?
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed.
> Text in the Subject and Body of the message will be
> ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com
like 80 cents and easy to rig up.
Original Message
From: <ghidera2000@y...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, December 19, 2002 10:34 AM
Subject: [noparse][[/noparse]basicstamps] Detecting 110 AC
> I have a little project where I need to count the number of times a
> liquid level sensor activates. The sensor shuts off a 110 solinoid,
> so all I need to do is check for voltage and increment a counter.
>
> Whats a simple way to sense the voltage that would provide isolation?
> I was thinking I could just wrap a wire around the hot and check it
> for voltage - inductive type thing.
>
> Any other simple methods folks use?
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>
> i used a hall effect sensor for similar purposes - they're only
something
> like 80 cents and easy to rig up.
Actually, now that I devote a couple braincells to this - I realized
my "inductive thingy" would give me an AC signal. I've not used hall
effect sensors before, would those not also give an AC signal?
I guess I could use a diode to limit the current to one direction and
a cap to keep the voltage up during the negative part of the cycle...
The opto sensor is pretty cool but not available locally and quite
pricey. Bookmarked it for later reference though, I have a half
formed idea for another project that this would probably be
worthwhile for. This current gizmo is just for temporary use, I'll be
cannabalizing it in March when we shut down the ice rink. Just want
to see if the ammonia high level limit ever actually triggers and, if
so, how many times.
about detecting current leakage on AC lines using this sensor. When I look
around though, most of the sensors are rated for pretty low voltage, though
I guess you could just slap a circuit to convert to a lower voltage DC
parallel to the AC just for purposes of sensing - transformer, bridge
rectifier, and capacitor are about $8 total at any radio shack. I'm kind of
new to this stuff, but that's similar to the way I've used these sensors.
ian
Original Message
From: <ghidera2000@y...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, December 19, 2002 4:17 PM
Subject: [noparse][[/noparse]basicstamps] Re: Detecting 110 AC
> --- In basicstamps@yahoogroups.com, "ian" <ian@n...> wrote:
> > i used a hall effect sensor for similar purposes - they're only
> something
> > like 80 cents and easy to rig up.
>
> Actually, now that I devote a couple braincells to this - I realized
> my "inductive thingy" would give me an AC signal. I've not used hall
> effect sensors before, would those not also give an AC signal?
>
> I guess I could use a diode to limit the current to one direction and
> a cap to keep the voltage up during the negative part of the cycle...
>
> The opto sensor is pretty cool but not available locally and quite
> pricey. Bookmarked it for later reference though, I have a half
> formed idea for another project that this would probably be
> worthwhile for. This current gizmo is just for temporary use, I'll be
> cannabalizing it in March when we shut down the ice rink. Just want
> to see if the ammonia high level limit ever actually triggers and, if
> so, how many times.
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>
Opto22 G4IACxx is pretty spiffy but more expensive than a relay.
I bought a Aromat HA1-AC115V and a 12K 1-watt resistor Minimum
operating current is 8ma so with the 12K I should get around 9-10 ma
max. I'll hook it up in parallel with the solinoid and then run a 5 v
signal line from the contacts to the stamp (pulled high). I'll do a
simple loop, checking the pin for voltage. If I detect voltage, set
a "counted" variable (dont increment if its set) and increment the
counter. When there is no power detected I'll set "counted" to zero.
Picked up two 7 segment displays and a couple 74LS47Ns, see how you
go about displaying the count on them. Should be simple enough (Yay
DIG command!).
Thanks the the suggestions everyone!
--- In basicstamps@yahoogroups.com, Jim Higgins <HigginsJ@s...> wrote:
> How about a small relay activated in parallel with the solenoid
coil. A
> set of contacts could switch either a logic high or logic low, your
choice,
> to a Stamp pin. This also gives you isolation from 110 VAC as well
as the
> inductive spike from the solenoid. The relay coil must have a
suitable
> duty cycle.
>
>
> Jim H