any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?
--
Vass

Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

Can't see any problem as long as it can cope with the DC amps.

"Vass" wrote in message
. uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should be
fine on 12V.

All switches have different ratings for AC and DC switching.
In general you need to look at the maximum current it will switch to see if
it will break that current without welding itself. The current will be
significantly lower for DC switching.

"dennis@home" wrote in message
...


"Vass" wrote in message
. uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should be
fine on 12V.

All switches have different ratings for AC and DC switching.
In general you need to look at the maximum current it will switch to see
if it will break that current without welding itself. The current will be
significantly lower for DC switching.


cool, ta
--
V

On Mon, 20 Jul 2009 11:21:18 +0100, "Vass" wrote:

any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

It all depends on the motor.

The switch is rated at 6A AC (3A AC on inductive loads) On DC that
rating will probably be less than 1 Amp. The switch capability
depends upon its current handling capability and the current breaking
capacity of the switch. It is the second which is much lower at AC
than DC.

A pneumatic switch may also have a relatively slow switching action,
this will derate it more on DC.

Motors are inductive loads and generate high current sparks at switch
off.. You can protect the switch to some extent by fitting a snubber
across it - 0,1mfd and a 47R resistor in series.

In article ,
Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

How much current does the motor take? Motors are inductive devices which
produce back EMF when switched off and likely to cause arcing on an AC
switch - unless very small.

--
*Suicidal twin kills sister by mistake.

Dave Plowman London SW
To e-mail, change noise into sound.

Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

Three possible reasons.

1/. Current is excessive for the contacts. Motors on 12v take big
startup currents and generate nasty flyback voltages when the current is
cut..

2/. Contacts are not designed to suppress a DC arc. AC tends to kill
the arc a bit quicker, as there are periods of 'no voltage'

3/. Its a solid state switch designed for AC only..;-)

"The Natural Philosopher" wrote in message
...
Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

Three possible reasons.

1/. Current is excessive for the contacts. Motors on 12v take big startup
currents and generate nasty flyback voltages when the current is cut..

2/. Contacts are not designed to suppress a DC arc. AC tends to kill the
arc a bit quicker, as there are periods of 'no voltage'

3/. Its a solid state switch designed for AC only..;-)

any other ideas then, I need people to casually switch on as they walk by
and it run for a short while
--
Vass

On Mon, 20 Jul 2009 16:38:47 +0100, "Vass" wrote:


any other ideas then, I need people to casually switch on as they walk by
and it run for a short while

The switch you are looking at isn't electronic so it will work happily
on 12V. Whether the contacts will survive depends on the motor rating
- if you can let us know what it is you can get a more precise answer.
If not you can always use the switch to switch a relay and the relay
to control the motor.

In message , "dennis@home"
writes


"Vass" wrote in message
.uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should
be fine on 12V.

Did you mean rated voltage there, braniac ?

With high current low voltage applications on mains switched, you can
get a build up on the contacts which, over time, increases the contact
resistance.

You can also get switch burn due to the back emf stored in the motor
windings on switch off


--
geoff

In article ,
Vass wrote:

"The Natural Philosopher" wrote in message
...
Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

Three possible reasons.

1/. Current is excessive for the contacts. Motors on 12v take big
startup currents and generate nasty flyback voltages when the current
is cut..

2/. Contacts are not designed to suppress a DC arc. AC tends to kill
the arc a bit quicker, as there are periods of 'no voltage'

3/. Its a solid state switch designed for AC only..;-)

any other ideas then, I need people to casually switch on as they walk
by and it run for a short while

Use the switch to operate a relay with 12 volt coil. A car 30 amp one
would be ideal - the coil on those draws about 0.1 amp. They're about a
fiver in Halfords - or pennies from a breaker.

--
*Remember not to forget that which you do not need to know.*

Dave Plowman London SW
To e-mail, change noise into sound.

"geoff" wrote in message
...
In message , "dennis@home"
writes


"Vass" wrote in message
t.uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should be
fine on 12V.

Did you mean rated voltage there, braniac ?

I meant what I said.


With high current low voltage applications on mains switched,

Did you mean mains switches there, braniac?

Hint.. don't start nit picking when your English is so poor.

Vass wrote:

"The Natural Philosopher" wrote in message
...
Vass wrote:
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a motor?

Three possible reasons.

1/. Current is excessive for the contacts. Motors on 12v take big
startup currents and generate nasty flyback voltages when the current
is cut..

2/. Contacts are not designed to suppress a DC arc. AC tends to kill
the arc a bit quicker, as there are periods of 'no voltage'

3/. Its a solid state switch designed for AC only..;-)

any other ideas then, I need people to casually switch on as they walk
by and it run for a short while

Don't get me wrong, it may work. It may not work for long. It may not
work at all.

What you concoct to do this depends on your skills and what stuff you
have to hand.

Id probably do something with a CMOS chip, a resistor and a capacitor
and a power transistor.

"The Natural Philosopher" wrote in message
...

Don't get me wrong, it may work. It may not work for long. It may not work
at all.

What you concoct to do this depends on your skills and what stuff you have
to hand.

skills? 50-50
stuff - zero


Id probably do something with a CMOS chip, a resistor and a capacitor and
a power transistor.

Whoosh!

Will try the push button, its only got to work for 3 weeks.
--
Vass

In article ,
Vass wrote:
Will try the push button, its only got to work for 3 weeks.

If you gave details of the motor it might be possible to make an educated
guess.

--
*I don't work here. I'm a consultant

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Vass wrote:
Will try the push button, its only got to work for 3 weeks.

If you gave details of the motor it might be possible to make an educated
guess.

I would guess that its the wheel chair motor he is attaching to his
turntable.

It shouldn't take much power as its low geared and lightly loaded from what
has been posted in the other thread.
Probably 1-4 amps.

"dennis@home" wrote in message
...


"Dave Plowman (News)" wrote in message
...
In article ,
Vass wrote:
Will try the push button, its only got to work for 3 weeks.

If you gave details of the motor it might be possible to make an educated
guess.

I would guess that its the wheel chair motor he is attaching to his
turntable.

It shouldn't take much power as its low geared and lightly loaded from
what has been posted in the other thread.
Probably 1-4 amps.
absolutley no writing on the motor or gearbox, so I have no idea
sorry should have said
--
Vass

"dennis@home" wrote in message
...


"geoff" wrote in message
...
In message , "dennis@home"
writes


"Vass" wrote in message
et.uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should be
fine on 12V.

Did you mean rated voltage there, braniac ?

I meant what I said.


With high current low voltage applications on mains switched,

Did you mean mains switches there, braniac?

Hint.. don't start nit picking when your English is so poor.

To be fair, your post was ambiguous, I assume you meant
"The RATED voltage OF THE SWITCH needs to be higher than the supply so a
240V switch should be
fine on 12V."?

"Toby" wrote in message
...
"dennis@home" wrote in message
...


"geoff" wrote in message
...
In message , "dennis@home"
writes


"Vass" wrote in message
news:zMGdnT33l4qD2PnXnZ2dnUVZ8jOdnZ2d@eclipse. net.uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should
be fine on 12V.

Did you mean rated voltage there, braniac ?

I meant what I said.


With high current low voltage applications on mains switched,

Did you mean mains switches there, braniac?

Hint.. don't start nit picking when your English is so poor.

To be fair, your post was ambiguous, I assume you meant
"The RATED voltage OF THE SWITCH needs to be higher than the supply so a
240V switch should be
fine on 12V."?


It wouldn't have made much sense in another random context.

However geoff is a pita that just likes to try and score points even though
he isn't very good at it.
As you can see he understood what I posted but feels the need to try and
make out he knows more.
I don't know why he does this but its his problem to work on.
I don't expect him to take the hint either as its too subtle and he won't
understand it.

On Tue, 21 Jul 2009 09:09:06 +0100, "dennis@home"
wrote:


It shouldn't take much power as its low geared and lightly loaded from what
has been posted in the other thread.
Probably 1-4 amps.

Wheelchair motors loaded can draw 20 -40 amps, they are usually rated
at 250W continuous and 500W peak. Although they won't draw anything
like this in the application contemplated they also have horrible
switching spikes. If it is a wheelchair motor I'd be inclined to put
a relay on the switch (a very simple job) and switch the motor on the
relay contacts.

If you salvage (or buy) a "standard" Bosch type car relay the
contacts will be numbered.

Connect relay contact 86 to bty negative.
Connect one terminal of the pneumatic switch to bty positive.
Connect the other terminal of the pneumatic switch to relay contact 85
Connect relay contact 87 to battery positive.

Connect the motor negative to battery negative.
Connect motor positive to relay contact 30.

These relays all use standard Lucar blade connectors.

"Peter Parry" wrote in message
...
On Tue, 21 Jul 2009 09:09:06 +0100, "dennis@home"
wrote:


It shouldn't take much power as its low geared and lightly loaded from
what
has been posted in the other thread.
Probably 1-4 amps.

Wheelchair motors loaded can draw 20 -40 amps, they are usually rated
at 250W continuous and 500W peak. Although they won't draw anything
like this in the application contemplated they also have horrible
switching spikes.

ooerrr, do I run the risk of electrocuting Joe Public?
--
Vass

Vass wrote:
Wheelchair motors loaded can draw 20 -40 amps, they are usually rated
at 250W continuous and 500W peak. Although they won't draw anything
like this in the application contemplated they also have horrible
switching spikes.

ooerrr, do I run the risk of electrocuting Joe Public?

No.

OK, long answer: 12v continuous isn't anywhere near enough to even feel
- unless Joe is keen on chewing the wires - and any back EMF switching
spikes won't have enough power to give you more than a tingle. Won't
even hurt.

Andy

In message , "dennis@home"
writes


"Toby" wrote in message
...
"dennis@home" wrote in message
...


"geoff" wrote in message
...
In message , "dennis@home"
writes


"Vass" wrote in message
news:zMGdnT33l4qD2PnXnZ2dnUVZ8jOdnZ2d@eclipse .net.uk...
any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch
should be fine on 12V.

Did you mean rated voltage there, braniac ?

I meant what I said.


With high current low voltage applications on mains switched,

Did you mean mains switches there, braniac?

Hint.. don't start nit picking when your English is so poor.

To be fair, your post was ambiguous, I assume you meant
"The RATED voltage OF THE SWITCH needs to be higher than the supply
so a 240V switch should be
fine on 12V."?


It wouldn't have made much sense in another random context.

However geoff is a pita that just likes to try and score points even
though he isn't very good at it.
As you can see he understood what I posted but feels the need to try
and make out he knows more.
I don't know why he does this but its his problem to work on.
I don't expect him to take the hint either as its too subtle and he
won't understand it.


Dennis, dennis, dennis - you're just a ****

--
geoff

"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor drivers and
you fall into both categories.

On Tue, 21 Jul 2009 16:52:38 +0100, "Vass" wrote:


ooerrr, do I run the risk of electrocuting Joe Public?

No - but you do need to take care that the drive shaft is reasonably
protected, a wheelchair motor (if that is what you are using) has a
lot of torque and is more than powerful enough to ingest small
children who get clothes entangled in it.

In message , "dennis@home"
writes


"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor drivers
and you fall into both categories.

I'm not upset, neither am I stupid, or a poor driver

You're just a ****

--
geoff

In message , geoff
writes
In message , "dennis@home"
writes


"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor
drivers and you fall into both categories.

I'm not upset, neither am I stupid, or a poor driver

You're just a ****


At least a ****'s useful
--
Kenny

Vass wrote:

"Peter Parry" wrote in message
...
On Tue, 21 Jul 2009 09:09:06 +0100, "dennis@home"
wrote:


It shouldn't take much power as its low geared and lightly loaded
from what
has been posted in the other thread.
Probably 1-4 amps.

Wheelchair motors loaded can draw 20 -40 amps, they are usually rated
at 250W continuous and 500W peak. Although they won't draw anything
like this in the application contemplated they also have horrible
switching spikes.

ooerrr, do I run the risk of electrocuting Joe Public?

No. You might at the worst give someone a nasty belt though. A stalled
electric motor is a bit like a car ignition coil primary. You can get a
couple of hundred volts spike if you break the circuit.

Andy Champ wrote:
Vass wrote:
Wheelchair motors loaded can draw 20 -40 amps, they are usually rated
at 250W continuous and 500W peak. Although they won't draw anything
like this in the application contemplated they also have horrible
switching spikes.

ooerrr, do I run the risk of electrocuting Joe Public?

No.

OK, long answer: 12v continuous isn't anywhere near enough to even feel
- unless Joe is keen on chewing the wires - and any back EMF switching
spikes won't have enough power to give you more than a tingle. Won't
even hurt.

I beg to differ, having played with a Meccano motor and a train
transformer in my youth. The back emf is several hundred volts. A LOT
more than a tingle.

I jumped across te bedroom and banged my knee.

Ok its not quite in the 'hold that plug while I test the spark on that
2-stroke' league, but its still a jolt to be reckoned with..

Andy

dennis@home wrote:


"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor drivers
and you fall into both categories.

Ah, no, That's YOU dennis.

geoff wrote:
In message , "dennis@home"
writes


"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor
drivers and you fall into both categories.

I'm not upset, neither am I stupid, or a poor driver

You're just a ****

A teflon coated one....


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

"Peter Parry" wrote in message
...
On Tue, 21 Jul 2009 16:52:38 +0100, "Vass" wrote:


ooerrr, do I run the risk of electrocuting Joe Public?

No - but you do need to take care that the drive shaft is reasonably
protected, a wheelchair motor (if that is what you are using) has a
lot of torque and is more than powerful enough to ingest small
children who get clothes entangled in it.


thanks for concern, but button is over the fence, the turntable is not
accessible to anyone but me
--
Vass

In message , The Natural Philosopher
writes
ooerrr, do I run the risk of electrocuting Joe Public?

No. You might at the worst give someone a nasty belt though. A stalled
electric motor is a bit like a car ignition coil primary. You can get a
couple of hundred volts spike if you break the circuit.
But surely the switch will be built in such a way that it's at least
difficult to touch the live parts? As long as the OP takes care to
enclose the wiring and switch terminals I don't think he's got much to
worry about and wouldn't the back emf from an interrupted circuit on a
spinning motor be higher (seems to make sense but I'm wondering)?
--
Clint Sharp

In message , Kenny writes
In message , geoff
writes
In message , "dennis@home"
writes


"geoff" wrote in message
...


Dennis, dennis, dennis - you're just a ****

You are just upset because I hate really stupid people and poor
drivers and you fall into both categories.

I'm not upset, neither am I stupid, or a poor driver

You're just a ****


At least a ****'s useful

Hmm, yes - maybe he was right about my use of English, I need a more
derogatory term, but even a pile of steaming **** is useful as
fertilizer.


--
geoff

On Jul 20, 8:39*am, "dennis@home"
wrote:
"Vass" wrote in message

. uk...

any reason I cannto use this
"COLUMBUS 400 PNEUMATIC TIME DELAY SWITCH"
on a 12volt battery to a moto

The voltage needs to be higher than the supply so a 240V switch should be
fine on 12V.

All switches have different ratings for AC and DC switching.
In general you need to look at the maximum current it will switch to see if
it will break that current without welding itself. The current will be
significantly lower for DC switching.

Ahem! Do you mean to say "The current 'rating' of the switch will be
lower if used to switch off/on DC amps. Especially so since the DC
amps are via a motor with inductive windings".