Door sensor battery life

Ok so about 23 days ago I did the sensor hack where do took the magnetic Reed sensor off and added wires in its place. Hooked those wires to a non lighted basic door bell switch and created a routine in Alexa so that it would alarm where the button is pushed. Ok so here it is 22 days later and I am awoken at midnight to my Echo sounding off the door bell sound like someone is pushing the button over and over. So I turn off the routine and look at the wyze app and realize the battery is almost dead. So why would this kill the battery in less than a month. Is it because it is constantly open? Do to the Reed switch being gone and the wires not connected unless the button is pushed? I was raining really hard that night but the door is at least 5 feet under the porch.

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Just conjecturing here but it looks like you have some fairly heavy gage wire there for a low power battery to push current thru. Could be that every time you used the button it put more drain on the battery than was planned on in the sensor and caused it to drain faster, even though it has enough power to operate initially. I’m not an EE guy but this seems feasible.
How much did you use it?

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You may want to consider a ‘push to make and push to break’ switch. As I understand the contact sensor’s read switch, a signal pulse occurs when the state of the reeds in the red switch changes. When the reeds are open or closed no current flows. Only upon change of the reeds does a pulse occur.
Good luck.

I am using a push to make switch, It is a normal doorbell switch. It only allows current to flow when the button is pushed. As for the amount of use, I think the button has only been pushed approximately 20 times in that 22 days. Now it should also be noted that at midnight when I woke up to this, my wife checked the wyze cam v2 that is on our front porch and the video feed would not pull up and then said it was disconnected. The cam is in one of the plastic casings from Amazon. As for the gauge of wire, idk know much about that. I just found some spare wire.

would check the air gap in switch. maybe the moisture made the contact.

if you have the in side doorbell still. maybe add a relay to trigger the sensor

Hello pavilion5
When the contact sensor’s magnet is brought in contact with its sending unit the LED flashes once and stays off as long at the magnet maintains contact. When the magnet is taken away from the sending unit (sufficiently far) the LED flashes once and stay off as long as the magnet stays sufficiently far enough away. The doorbell switch needs to make and keep contact or break contact and stay open. That continuous contact or continuous open is what the magnet’s changed proximity provides. A simple one-way (single-pole) switch will mimic the behavior of the magnet. My hunch is that the connecting wire should be 24 to 28 AWG.

When I was preparing to modify a contact sensor by removing its reed switch and soldering two wire leads where it used to connect to the circuit board, I did a test. Before removing the reed switch, I shorted out the reed with a little piece of wire and held the short in place, the LED flashed once and remained off. When I removed the short the LED flashed once and remained off. This is what the magnet does. when it is close it shorts the reed switch and when far enough away it does not short the reed switch. An easier way to do this test is to remove the adhesive on the sending unit’s door and insert a small diameter jumper wire through the two holes in the case door that line up with the soldered ends of the reed switch (probably for production line testing).

I think if you can find a doorbell switch with the action of a very small one-way (single-pole) type, your battery drain problems will go away or at least be significantly less.
Victor Maletic.

Yea I fully understand how it works, I just mean I don’t know the math on wire gauge off the top of my head. As for the moisture making the doorbell switch make the contact, that is probably what happened. The gap on the contacts, for the switch is less than a 1/4". Also my wire gauge is probably too big.

is telephone and thermostat wire

Yea that’s what I’m gonna do is take it back apart and put one of those gauge wires. Should I go with a solid core wire or strand wire?

Solid is use where the thing not going to move. Strand wire is like a extension cord.

sorry, but I have to ask how do you know that the battery was at optimal power supplying conditions when you purchased it?

Given how these batteries are such a commodity today, it’s hard for me to tell at the time of purchase which ones are good for the long-haul. For me it’s a super SWAG!

It is a China battery so it no telling. cr1632
If I need a long life

Yea it could have been a crappy battery out the package, I’ll never know. Upgrading the battery to that CR124A is a good idea. I’ll probably end up doing that as well. What kind of switch could I get to avoid the moisture bridging the contacts of the switch? I really only want this setup to last until Wyze makes a video doorbell.

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I think doorbell switch come with black paper backing. I would just use tape to cover up the back.

The battery cr124 is used in the z wave stuff. I would go to one for a garage door sensor where I can mount the battery.

Sounds good thanks kroq83

wyze sensor

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Yea that’s the video I used to do it originally.

Good to know, thanks.

I ment to say stranded wire.

From what I recall from my old GE days decreasing the aggregate diameters of the conductors in an electrical cable of a given length resulted in an increased resistance. It’s probably a curve rather than a straight line. But larger cross ares = lower resistance = lower losses.