At our firehouse we have a siren that is set off by tones from the county. An old plectron tone decoder is used and has what I would assume to be relay outputs on the back. I am trying to understand this setup. Not trying to attempt any work on it, just wondering how it all works. I understand the plectron receives the tones and is tripped internally to the terminals on the back. From there, its wired into a large custom box on the wall (approx 12"x24"). In there, there is a timer that when setup used to disable the siren at 10 pm if I remember right. There are also what several people have told me are 'tumblers'. Neither they nor I know what these do, but that is the name I know them by. There is a copy of the hand drawn schematic in the box, as one of the members who is an electrician designed this years ago. As a side note, this setup also triggers 3 bay doors to open up when the tones are hit. Anyone want to venture a guess and try to explain this to me?
Thanks, Ryan
Trying to understand a two tone activated siren
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In this application typically there will be two control outputs from the Plectron. A momentary output that will be connected to the door opener control & a continuous (until reset) output for the station siren.
The continuous output of the Plectron controls a relay that controls the tumbler. The tumbler typically is a motor with a cam on it that switches the siren on & off. As the motor turns the cam closes and opens a switch that supplies power to the siren through a high current relay. That way the siren rises and falls in a pattern.
The ones like this that we have at our volunteer contract stations self reset after two minutes.
Plectron went out of business quite some time ago. There are almost no parts available anywhere for these units. Apparently they were very well made; the ones around here have been in continuous service for more than 30 years with almost no failures.
When yours finally breaks you can replace it with a Minitor V with amplified charger for pennies on the dollar of the original cost of that unit.
The continuous output of the Plectron controls a relay that controls the tumbler. The tumbler typically is a motor with a cam on it that switches the siren on & off. As the motor turns the cam closes and opens a switch that supplies power to the siren through a high current relay. That way the siren rises and falls in a pattern.
The ones like this that we have at our volunteer contract stations self reset after two minutes.
Plectron went out of business quite some time ago. There are almost no parts available anywhere for these units. Apparently they were very well made; the ones around here have been in continuous service for more than 30 years with almost no failures.
When yours finally breaks you can replace it with a Minitor V with amplified charger for pennies on the dollar of the original cost of that unit.
Wyrd bið ful ãræd, Fate is inexorable...
I agree that the Plectron's were well built. Ours has at least 20 or more years on it. I'm not sure how ours is setup for the timing, but the siren will go through two revolutions and then shut off. With the doors, is that output just run to a relay that triggers the same line that the open button on the wall operates? Now for kicks, how hard would it be to wire the lighting on the apparatus floor to come on with this? Just curious. Thanks for the excellent explanation.
Ryan
Ryan
Yes, the door opener works pretty much as you thought.
As far as lighting for the apparatus floor, you could use a latching relay on the same output.
What would be even better, and we use these at our stations, is a motion detector mounted on the ceiling. At night, if no one is out in the bays the lights are off. As soon as there is some motion, the lights come on. One advantage is that if we are out at night the bays will be dark and someone driving by with ill intent can't really tell if we are gone. The motion of the door coming up is enough to turn them back on when we come back.
Either way, hire a licensed electrician to do the work. That way it can't be said that you burned the fire station down.
Robert
As far as lighting for the apparatus floor, you could use a latching relay on the same output.
What would be even better, and we use these at our stations, is a motion detector mounted on the ceiling. At night, if no one is out in the bays the lights are off. As soon as there is some motion, the lights come on. One advantage is that if we are out at night the bays will be dark and someone driving by with ill intent can't really tell if we are gone. The motion of the door coming up is enough to turn them back on when we come back.
Either way, hire a licensed electrician to do the work. That way it can't be said that you burned the fire station down.
Robert
Wyrd bið ful ãræd, Fate is inexorable...
We have a similar setup at our station. Plectron, installed sometime in the 70's, still in operation w/ no issues. Siren is, massive and runs off 3 phase current.
Our only issue is when we are at the station (all volunteer) and we get a call, the siren is so loud (mounted between 2 telephone poles 30' high outback of the building) that you can not hear the dispatch traffic. This often results in someone cutting the main breaker off to the siren and then forgetting to turn it back on before leaving.
I have been interested in installing some type of relay setup that is tied into the light switch for the dayroom/office/work area that disables the siren when it the room lights are on. This way, as long as someone is there (99% of the time if someone is there the lights are on) the siren would not blow, but as soon as someone would leave, the lights are cut off and the siren is back in service. Installing a timer is not acceptable in our situation because many times during the daylight hours there is no one there due to us being totally volunteer.
Anyone done anything similar to this before?
Wes
Our only issue is when we are at the station (all volunteer) and we get a call, the siren is so loud (mounted between 2 telephone poles 30' high outback of the building) that you can not hear the dispatch traffic. This often results in someone cutting the main breaker off to the siren and then forgetting to turn it back on before leaving.
I have been interested in installing some type of relay setup that is tied into the light switch for the dayroom/office/work area that disables the siren when it the room lights are on. This way, as long as someone is there (99% of the time if someone is there the lights are on) the siren would not blow, but as soon as someone would leave, the lights are cut off and the siren is back in service. Installing a timer is not acceptable in our situation because many times during the daylight hours there is no one there due to us being totally volunteer.
Anyone done anything similar to this before?
Wes
Wes Hutchens
911 Telecommunicator/2-Way Sales & Service
911 Telecommunicator/2-Way Sales & Service
Wes, With your setup, does the siren sound with the pager tone? Or is it toned out before the pagers on its own tone? With ours, the siren has its own tone, that is the setup for the entire county. When we get a call, the county comm center tones the pagers, gives the dispatch, and then hits the siren tones after all of the dispatch info is given. In this setup, no dispatch information is missed.
-Ryan
-Ryan
Get an electrician to put a "delay on" relay into the setup. It can be set anywhere from tenths of a second to hours to delay the start of the siren. I'd set it for 30 or 45 seconds, plenty of time to hear the message before the siren starts.
Jay Goldmark, EMT
Ex-Captain, Woodmere Vol. Fire Dept.
Fire District Communications Supv.
KC2ZHI Amateur Radio Operator
Licensed Master Electrician
Owner, Top Class Electric, LLC.
Woodmere, Long Island, NY
"Enjoy Life, it's not a dress rehearsal !!!"
************************************************************
Ex-Captain, Woodmere Vol. Fire Dept.
Fire District Communications Supv.
KC2ZHI Amateur Radio Operator
Licensed Master Electrician
Owner, Top Class Electric, LLC.
Woodmere, Long Island, NY
"Enjoy Life, it's not a dress rehearsal !!!"
************************************************************
Ours is set up with a seperate set of tones from the pagers. Asking our Communications to encode the siren tones seperate after the dispatch would be like an act of congress. That will not happen.
Jay, your idea is not bad though, I'll look into it further....
thanks for the tip.
Wes
Jay, your idea is not bad though, I'll look into it further....
thanks for the tip.
Wes
Wes Hutchens
911 Telecommunicator/2-Way Sales & Service
911 Telecommunicator/2-Way Sales & Service
Wes,
Did you ever get your siren working the way you wanted?
I install controllers that take the momentary contact and start the siren. You can stop it with a push button, or start it with another button. The time of day the siren operates can be set as well. Automatically turn off siren after a set number of cycles.
Also give outputs to open doors and turn on lights too.
It can be set short cycle siren and keep doors locked during the test page time (ie test page is saturday at 12 noon, unit will single cycle siren and not unlock doors if a page is recieved at 12 noon +/- 5 minutes)
I think this is what you are wanting.
Bruce
Did you ever get your siren working the way you wanted?
I install controllers that take the momentary contact and start the siren. You can stop it with a push button, or start it with another button. The time of day the siren operates can be set as well. Automatically turn off siren after a set number of cycles.
Also give outputs to open doors and turn on lights too.
It can be set short cycle siren and keep doors locked during the test page time (ie test page is saturday at 12 noon, unit will single cycle siren and not unlock doors if a page is recieved at 12 noon +/- 5 minutes)
I think this is what you are wanting.
Bruce