How to handle a latching valve/relay - mosfet ?
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--- In basicstamps@yahoogroups.com, "Jonathan Peakall"
<jpeakall@m...> wrote:
> Hi All,
>
> What is the best way to use a latching valve or relay? The polarity
to the
> relay/valve must be reversed to open/close the valve.
>
> Jonathan
>
> www.madlabs.info
if you are looking for a low power consumption - high power device,
look at something like a MOSFET. the mechanical coil stuff will use
more power and that is the benefit of a latching relay.
The latching relay will change state with a pulse and remain in the
current state, but I think that if you need the power to operate the
solenoid, you will have more then enough to power a MOSFET in
addition to the solenoid.
IF you are talking a piloted air(gas) valve that opens the pressure
and pressure then holds the valve open, that would eleminate the need
for an electircal power source
Dave
<jpeakall@m...> wrote:
> Hi All,
>
> What is the best way to use a latching valve or relay? The polarity
to the
> relay/valve must be reversed to open/close the valve.
>
> Jonathan
>
> www.madlabs.info
if you are looking for a low power consumption - high power device,
look at something like a MOSFET. the mechanical coil stuff will use
more power and that is the benefit of a latching relay.
The latching relay will change state with a pulse and remain in the
current state, but I think that if you need the power to operate the
solenoid, you will have more then enough to power a MOSFET in
addition to the solenoid.
IF you are talking a piloted air(gas) valve that opens the pressure
and pressure then holds the valve open, that would eleminate the need
for an electircal power source
Dave
Comments
Omron has some low power DPDT relays. The switch portion can handle 0.5
amp at 125 volt AC or 1 amp at 30 volts DC.
Non-latching (G6H-2) can be actuated with 5 volts and 28 milliamps.
Latching single coil (G6HU-2) can be actuated with 5 volts 20 milliamps.
Latching dual coil (G6HK-2) can be actuated with 5 volts 50 milliamps.
Digi-Key has some of the non latching in stock $4 a piece, Digi-Key#:
Z740-ND. They don't appear to have any of the low power single-coil
latching types in stock (Digi-Key#: G6HU-2-DC5-ND). But they do have some
dual coil latching types (Digi-Key#: Z965-ND) $4.85 a piece.
28 milliamps is just under the limit for a Stamp pin and 50 is much more,
but thats what transistors are for right?
I think they are sealed relays. I can't find it in the spec sheet, but I
have some G6H-2 and they look sealed to me. Of course you should get
confirmation from Omron before using them in a hazardous environment.
Chuck Chargin Jr.
At 03:36 AM 6/26/2003 +0000, you wrote:
>--- In basicstamps@yahoogroups.com, "Jonathan Peakall"
><jpeakall@m...> wrote:
> > Hi All,
> >
> > What is the best way to use a latching valve or relay? The polarity
>to the
> > relay/valve must be reversed to open/close the valve.
> >
> > Jonathan
> >
> > www.madlabs.info
>
>
>if you are looking for a low power consumption - high power device,
>look at something like a MOSFET. the mechanical coil stuff will use
>more power and that is the benefit of a latching relay.
>
>The latching relay will change state with a pulse and remain in the
>current state, but I think that if you need the power to operate the
>solenoid, you will have more then enough to power a MOSFET in
>addition to the solenoid.
>
>IF you are talking a piloted air(gas) valve that opens the pressure
>and pressure then holds the valve open, that would eleminate the need
>for an electircal power source
>
>Dave
>
>
>
>
>
>
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