Door Hold Voltage

[GC]

We have these magnetic door holders at work....
ie there is a metal plate on the door, then bolted to the ground is a magnet
which is only energised when power is put on it.

Problem is, the only ones that I can order now are 24 volt door holds but I
only have a 12 volt supply. I can't change the power supply or put on an
extra one is it powers a security panel and a few other doors.

Apparently the original door holds were modified so that 12 volts can be
used.
I've tried hooking 12 volts up to a new one but the magnetisism isn't very
strong.
I haven't been able to get access to one of the supposedly modified ones so
I don't know what they have done....

Hopefully I have explained the situation properly..... my question to the
newsgroup is.... does anyone have any suggestions on how I could modify the
24 volt magnet to a 12 volt one??
All it has is a red and black coming directly out of the sealed magnet part
which goes through a push button switch (normally closed, for taking power
off manually). There is room in the bracket to add some components if need
be...
Perhaps the mod originally was to replace the magnet part of the door
hold..... that would probably be a hard task to try and locate a
replacement.
Any help would be most appreciated...... I can get 12 volt door holds, but
they look totally different and are plastic.... This particular one is
strong metal. part number is something like 830F is that means anything
to anyone.
Thanks!!

 

On Tue, 10 Feb 2004 17:41:01 +1100, "GC" <mobaccREMOVE@tig.com.au>
wrote:

We have these magnetic door holders at work....
ie there is a metal plate on the door, then bolted to the ground is a magnet
which is only energised when power is put on it.

These are the ones you're after:
http://www.trimec.com.au/padde/

http://www.speedintercom.com.au/ sell them to trade in Brisbane, they
might be able to help if you cant find someone local to you.

Problem is, the only ones that I can order now are 24 volt door holds but I
only have a 12 volt supply. I can't change the power supply or put on an
extra one is it powers a security panel and a few other doors.

They're dual-voltage. 12 and 24V operation.

Apparently the original door holds were modified so that 12 volts can be
used.
I've tried hooking 12 volts up to a new one but the magnetisism isn't very
strong.
I haven't been able to get access to one of the supposedly modified ones so
I don't know what they have done....

Hopefully I have explained the situation properly..... my question to the
newsgroup is.... does anyone have any suggestions on how I could modify the
24 volt magnet to a 12 volt one??

Buy a 24V powersuppy whack it adjacent the security panel. Use the old
feed from the security panel to power a 12V relay wired failsafe.
Power the door lock through the relay.

If its on a door, you're also going to have to look at battery back-up
too.

 

[Bob M]

"GC" <mobaccREMOVE@tig.com.au> wrote in message news:<c09ter$o0k$1@lust.ihug.co.nz>...

We have these magnetic door holders at work....
ie there is a metal plate on the door, then bolted to the ground is a magnet
which is only energised when power is put on it.

Problem is, the only ones that I can order now are 24 volt door holds but I
only have a 12 volt supply. I can't change the power supply or put on an
extra one is it powers a security panel and a few other doors.

Apparently the original door holds were modified so that 12 volts can be
used.

Did you verify that they are actually running on 24 volts? They may
have installed a 12 volt relay, controlled by the original system,
that controls a 24 volt supply feeding the magnetic door hold. This is
most likely your cheapest solution.

There are also DC to DC convertors availible. You would need a 12 to
24 volt version. These are not cheap and you would have to verify how
much current the magnetic hold draws to ensure the DC to Dc convertor
can supply the required power.

I've tried hooking 12 volts up to a new one but the magnetisism isn't very
strong.

The magnetic coil has a fixed resistance. 1/2 the voltage = 1/2 the
current = 1/4 the power (voltage X current) would result in
unsatisfactory operation.

I haven't been able to get access to one of the supposedly modified ones so
I don't know what they have done....

It would be worth the effort to get access and to make measurements,
otherwise you are just guessing at what is going on.

You need to do some homework (i.e. field work) if you want to do this
properly.

Cheers from Canada

Bob Morgoch

Hopefully I have explained the situation properly..... my question to the
newsgroup is.... does anyone have any suggestions on how I could modify the
24 volt magnet to a 12 volt one??
All it has is a red and black coming directly out of the sealed magnet part
which goes through a push button switch (normally closed, for taking power
off manually). There is room in the bracket to add some components if need
be...
Perhaps the mod originally was to replace the magnet part of the door
hold..... that would probably be a hard task to try and locate a
replacement.
Any help would be most appreciated...... I can get 12 volt door holds, but
they look totally different and are plastic.... This particular one is
strong metal. part number is something like 830F is that means anything
to anyone.
Thanks!!

 

[GC]

Putting in another power supply plus all the rest is out of the question. It
would require changing both door hold magnet, battery backup.
The only place that I can really make changes is at the door, I don't want
to touch the security panels at all.
Ideally I want to be able to modify the 24volt door holds that I can get, or
I'm going to have to get a shonky 12volt plastic one.. There might be other
metal ones.... but I really would prefer to use the SAME that installed at
the moment...
I don't think either of those companies will have them... Speed Intercom
is "Sprint" and Sprint don't have them.
And its not a PADDE lock.



<David Sauer> wrote in message
news:757h20hadj2bs5vllv2fcou85a1s951ilq@4ax.com...

On Tue, 10 Feb 2004 17:41:01 +1100, "GC" <mobaccREMOVE@tig.com.au
wrote:

We have these magnetic door holders at work....
ie there is a metal plate on the door, then bolted to the ground is a
magnet
which is only energised when power is put on it.

These are the ones you're after:
http://www.trimec.com.au/padde/

http://www.speedintercom.com.au/ sell them to trade in Brisbane, they
might be able to help if you cant find someone local to you.

Problem is, the only ones that I can order now are 24 volt door holds but
I
only have a 12 volt supply. I can't change the power supply or put on an
extra one is it powers a security panel and a few other doors.

They're dual-voltage. 12 and 24V operation.

Apparently the original door holds were modified so that 12 volts can be
used.
I've tried hooking 12 volts up to a new one but the magnetisism isn't
very
strong.
I haven't been able to get access to one of the supposedly modified ones
so
I don't know what they have done....

Hopefully I have explained the situation properly..... my question to
the
newsgroup is.... does anyone have any suggestions on how I could modify
the
24 volt magnet to a 12 volt one??

Buy a 24V powersuppy whack it adjacent the security panel. Use the old
feed from the security panel to power a 12V relay wired failsafe.
Power the door lock through the relay.

If its on a door, you're also going to have to look at battery back-up
too.

 

[GC]

Thanks for your help!
I know how the system works as I was involved with commisioning etc when it
was installed... but I had nothing to do with ordering the parts.... the
people who did have long gone
I should probably not be so lazy and see what I can find in the field.
Thanks for your help/suggestions.

"Bob M" <bmorgoch@sympatico.ca> wrote in message
news:512df638.0402100545.23b64ba3@posting.google.com...

"GC" <mobaccREMOVE@tig.com.au> wrote in message
news:<c09ter$o0k$1@lust.ihug.co.nz>...
We have these magnetic door holders at work....
ie there is a metal plate on the door, then bolted to the ground is a
magnet
which is only energised when power is put on it.

Problem is, the only ones that I can order now are 24 volt door holds
but I
only have a 12 volt supply. I can't change the power supply or put on
an
extra one is it powers a security panel and a few other doors.

Apparently the original door holds were modified so that 12 volts can be
used.

Did you verify that they are actually running on 24 volts? They may
have installed a 12 volt relay, controlled by the original system,
that controls a 24 volt supply feeding the magnetic door hold. This is
most likely your cheapest solution.

There are also DC to DC convertors availible. You would need a 12 to
24 volt version. These are not cheap and you would have to verify how
much current the magnetic hold draws to ensure the DC to Dc convertor
can supply the required power.

I've tried hooking 12 volts up to a new one but the magnetisism isn't
very
strong.

The magnetic coil has a fixed resistance. 1/2 the voltage = 1/2 the
current = 1/4 the power (voltage X current) would result in
unsatisfactory operation.

I haven't been able to get access to one of the supposedly modified ones
so
I don't know what they have done....

It would be worth the effort to get access and to make measurements,
otherwise you are just guessing at what is going on.

You need to do some homework (i.e. field work) if you want to do this
properly.

Cheers from Canada

Bob Morgoch


Hopefully I have explained the situation properly..... my question to
the
newsgroup is.... does anyone have any suggestions on how I could modify
the
24 volt magnet to a 12 volt one??
All it has is a red and black coming directly out of the sealed magnet
part
which goes through a push button switch (normally closed, for taking
power
off manually). There is room in the bracket to add some components if
need
be...
Perhaps the mod originally was to replace the magnet part of the door
hold..... that would probably be a hard task to try and locate a
replacement.
Any help would be most appreciated...... I can get 12 volt door holds,
but
they look totally different and are plastic.... This particular one is
strong metal. part number is something like 830F is that means
anything
to anyone.
Thanks!!