Problem solved! Dad came home and we tested it with a voltage meter. We determined the solenoid was fine. What was the problem? Simply the way I had the device angled when I tested it first. When I turned the device upright the second time with the plunger down, it chimed fine. I just have to keep the device upright when I test it and not sideways like how I had it the first time. Thanks for everyone’s help! I’m so glad it’s not AC!
Can you post a video?
Of course! I planned to show this device in Floor System Test 23 which I will film today. I’ll go hook it into the 4004 now and film it. My YouTube name is msj191961. Stay tuned for it!
WAIT!!! DONT WIRE IT TO YOUR PANEL YET
It does not appear to be diode polarized. If you do not know what that means, here is an explanation.
Diodes are essentially the electrical equivalent of a one way valve.
Diode polarization is used on alarm equipment to control which way the electricity flows. NAC supervision relies on this … when a NAC is normal it dumps 24 volts into the circuit but backwards. Since the signals are diode polarized, they will not sound. When the NAC sounds, the polarity flips around and then the diode allows power into the signal and it can sound.
I have a 712-24 chime as well - a fire alarm version - and it has a diode wired in series with the red wire. Since yours has two black wires that tells me it does not have any sort of diode polarization at all.
What you need to do is go to the store and get yourself a 1N4005 diode and wire it to one of the wires. Diodes have a stripe on one side which tells you which way it flows. Wire the diode so that the striped side is on the solenoid side. This will be your +. You only need one diode. The other wire will become your -. Test it on an external power source first before wiring it to your panel to verify that you did this properly.
I actually had to polarize my 4050-80 when I got it. I did wire it up to panel before reading this, and realized this needed to be polarized after I hooked it up to the batteries and the polarity didn’t matter. I had a spare 1N4001 diode that I slapped onto it, and it worked fine, but should I wait and get a 1N4005 instead?
Thank you for the reminder, though! I didn’t even realize that at first, but I suppose I should start doing checks of every older device I buy.
In addition to NAS’s recommendation to add a polarizing diode I notice something else that could damage your fire alarm panel. There is no coil back EMF suppression in this unit.
What is that you say? When a coil like is in this chime, or a relay coil, or any other magnetic device, when the power is cut to the coil a very large voltage spike can be generated. That is how the ignition coil in a car works to fire the spark plugs. Below is a picture of a little 24 volt DC relay generating a 240 volt spike when the power to the coil is cut off.
[attachment=2]unsupressed-relay-coil.jpg[/attachment]
Fire alarm devices have internal devices to suppress the back EMF from a coil to prevent causing a voltage spike that can cause damage to the electronics in the panel. Below is a picture of an old mechanical chime motor. Notice the little green device soldered across the coil. That is a Metal Oxide Varistor, MOV for short. It does not conduct until the voltage exceeds its rating. Then it conducts all the voltage above that level. This protects the fire alarm panel circuitry.
[attachment=1]FA-chime-mech.jpg[/attachment]
A second diode can be added to your device to suppress the back EMF to protect your panel. Get two diodes and connect them as shown below. The second diode across the coil will suppress the big voltage spike to protect your panel.
[attachment=0]polarized-with-suppression.jpg[/attachment]
Okay, I see. Thanks for letting me know! So, all in all, do I need 2 or 3 diodes? And what kind of diodes should I get? Same ones that NAS mentioned?
As my drawing shows you need 2 diodes. One to polarize the device and the other across the coil for suppression. And it has to be directly across the coil for best results. The 1N4005 NAS suggested is a 600 volt diode. The 1N4004 is a 400 volt diode which will work too. I used hundreds of them over the years in low voltage fire alarm. These are conveniently available in packages of 2 at the National Universal Parts Bank (Radio Shack). At least as long as they stay in business.
A 1N4001 works fine for what NAS is talking about. 1N4005’s will work a lot better for what STR is talking about.
A 1N4001 is good for 50 volts, a 1N4005 is good for 600volts.
Radio Shack still sells parts? Reminds me of the time I walked into the RS asking for a “male Motorola plug” for a car stereo, only to have they guy walk me over to the cell phone accessories rack and point out the Motorola branded stuff.
I believe what Y’all referring to is an induction coil. Kinda like a DC transformer.
Haha lol. Therse not a Radio Shack with in 20 miles of here. :roll:
Yeah, they still sell parts. They are in the drawers in the back corner of the store. That is the only thing I get at RS. However, you are correct, the “help” knows nothing about them. I always go to the web site to find the part number. Walk in with the part number and you might have a chance of finding what you want.
I am most of the way across the country from “Somewhere in Oregon.” So how should I know this? :?
It’s really a shame. I’ve heard many people that are skeptical as to if RadioShack will stay open. I sure hope they do. I’ve got one about a mile from my house that I always go to for fire alarm parts. I’m going to try to take a walk over there today to get those diodes and also some resistors since I broke my last NAC resistor yesterday on the chime.
RadioShack is convenient, but that is where they get you with their overpriced parts. You’re paying for the convenience of being able to walk in and get your parts right then. I always order my electronics parts from Tayda Electronics (http://www.taydaelectronics.com/). Great prices and quality, and they ship from the US. I would highly recommend them to all of you.
That is true. Maybe I’ll check that out. I actually just now found out that the store I was just talking about recently closed it’s doors. For anyone who’s curios, it will probably take me a few days to make this test. I’m probably going to have to get a diode soldered across the coil, since I don’t see any other way to get it on there.
What? That doesn’t make sense…
I prefer Mouser. NICEST people to deal with. Jameco wouldn;t help me at ALL. :roll:
Brandon, your signature is a bit of an eyesore…
I go to Ratshack only because it’s quick. No one who works there (at least the one near where I live) knows anything about electronics, only about phones and tablets and stuff. I can’t rely on them for any help. I asked one of them if they had DPDT relays and they looked at me as if I had lobsters crawling out of my ears.
Alright, everyone. While in Rockford yesterday, we ran to a RadioShack and I picked up a pack of 1N4005 diodes (and some extra resistors, haha). I added one to the chime tonight along with the polarization diode and hooked it back up to the 4004 and it performed flawlessly. I noticed while testing it that a problem that I had before adding the EMF diode was gone. Before adding that diode, the indicators on my 4004 were spazzing out and displaying all kinds of weird characters, but now that’s fixed, so I’m guessing the diode works.
Thank you, everyone (especially Retired STR-SG) for helping me get this chime going. Now that I’m sure it’s ready to go, I will make a test video with it tomorrow. You can go to my YouTube channel, msj191961, to check it out. Happy New Year to everyone!
P.S. If possible, I’d love to see a video of your 712 in the future, Andrew!