Currnet sensing
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Posts: 46,084
Hello stampers..···
Does anyone out there have a simple solution for sensing currnet from an AC motor?.
The motor is 240 volts ac and draws approx 5 Amps under load. I wish to simply run the active supply wire through a hand wound coil or similar and achieve a clean 5v - 0v signal at a stamp pin, with no physical contact with the mains power.
The circuit will be useful for automatically checking wether or not a bore pump has lost its prime (lower current draw at motor).
Any help would be appreciated.
Regards, Chris
Does anyone out there have a simple solution for sensing currnet from an AC motor?.
The motor is 240 volts ac and draws approx 5 Amps under load. I wish to simply run the active supply wire through a hand wound coil or similar and achieve a clean 5v - 0v signal at a stamp pin, with no physical contact with the mains power.
The circuit will be useful for automatically checking wether or not a bore pump has lost its prime (lower current draw at motor).
Any help would be appreciated.
Regards, Chris
Comments
if I still have a schematic.
Original Message
Does anyone out there have a simple solution for sensing currnet from an AC
motor?.
The motor is 240 volts ac and draws approx 5 Amps under load. I wish to
simply run the active supply wire through a hand wound coil or similar and
achieve a clean 5v - 0v signal at a stamp pin, with no physical contact with
the mains power.
Chris
Original Message
From: Rodent <daweasel@s...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, March 05, 2001 12:05 PM
Subject: Re: [noparse][[/noparse]basicstamps] Currnet sensing
> We built a device like this where I used to work. I'm check Tuesday to see
> if I still have a schematic.
>
>
Original Message
>
> Does anyone out there have a simple solution for sensing currnet from an
AC
> motor?.
> The motor is 240 volts ac and draws approx 5 Amps under load. I wish to
> simply run the active supply wire through a hand wound coil or similar and
> achieve a clean 5v - 0v signal at a stamp pin, with no physical contact
with
> the mains power.
>
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
mA output is linear to line current.
Any electrical store will have something. Jameco offers cheap units,
and if you are just playing around wrap a few hundred loops of
uninsulated, varnished transformer wire around a straw (electric
drill works well) to make your own. Just pass one lead through the
center. Be careful, the ends of the wire will carry current. Use a
resistor to limit the current and have fun scaling the output.
Dave
--- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> We built a device like this where I used to work. I'm check Tuesday
to see
> if I still have a schematic.
>
>
Original Message
>
> Does anyone out there have a simple solution for sensing currnet
from an AC
> motor?.
> The motor is 240 volts ac and draws approx 5 Amps under load. I
wish to
> simply run the active supply wire through a hand wound coil or
similar and
> achieve a clean 5v - 0v signal at a stamp pin, with no physical
contact with
> the mains power.
[noparse][[/noparse]basicstamps] Currnet sensing:
>Hello stampers..
>Does anyone out there have a simple solution for sensing currnet
>from an AC motor?.
>The motor is 240 volts ac and draws approx 5 Amps under load. I wish
>to simply run the active supply wire through a hand wound coil or
>similar and achieve a clean 5v - 0v signal at a stamp pin, with no
>physical contact with the mains power.
>The circuit will be useful for automatically checking wether or not
>a bore pump has lost its prime (lower current draw at motor).
>Any help would be appreciated.
>
I have wondered if this could be done with a simple reed switch. Wrap
JUST enough of the ac wire around the switch to make it close. If the
current drops ENOUGH when the motor starts freewheeling, the switch
should open.
Piece 'o cake for the stamp to monitor the switch.
Let us know if you try this (either it works or if it doesn't)
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Chuck Britton Education is what is left when
britton@n... you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 286-3366 x224 Albert Einstein, 1936
you might look at PumpSaver units from
http://www.symcominc.com
sense overcurrent, undercurrent, dead head, suck out
frequent cycling... there are other units available
also - such as motormind. None cheap :-(
I live on a rural pump system :-)
Consider sensing _pressure_ for loss of prime... simple.
>>
Date: Mon, 5 Mar 2001 11:45:14 +0800
From: "Chris Anderson" <fes@g...>
The circuit will be useful for automatically checking wether or
not a bore pump has lost its prime (lower current draw at motor).
Any help would be appreciated.
<<
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Monitor all the electrical parameters and even motor temperature.
I checked Jameco, their Current transformers sell for less than $1.00
for the small units, and less than $20 for the larger ones.
Dave
--- In basicstamps@y..., s premena <premzee@j...> wrote:
> For more ideas on sophisticated pump pump sesning
> you might look at PumpSaver units from
>
> http://www.symcominc.com
>
> sense overcurrent, undercurrent, dead head, suck out
> frequent cycling... there are other units available
> also - such as motormind. None cheap :-(
> I live on a rural pump system :-)
>
> Consider sensing _pressure_ for loss of prime... simple.
>
> >>
> Date: Mon, 5 Mar 2001 11:45:14 +0800
> From: "Chris Anderson" <fes@g...>
>
> The circuit will be useful for automatically checking wether or
> not a bore pump has lost its prime (lower current draw at motor).
> Any help would be appreciated.
> <<
>
> ________________________________________________________________
> GET INTERNET ACCESS FROM JUNO!
> Juno offers FREE or PREMIUM Internet access for less!
> Join Juno today! For your FREE software, visit:
> http://dl.www.juno.com/get/tagj.