I've had a Yale YRL226XW2 Z-Wave Lock for a couple of years and until the last few months, it consumed a set of (4) AA batteries every 3-4 months or so - maybe longer. They are now being consumed to approximately 20% in about 3 weeks. Nothing has changed related to the lock as far as I know. Is the best course of action at this point to remove it from the Z-Wave mesh and then set it back up again?
It's in use by:
[Amazon Echo Skill]
[Batteries To Watch - Tile2 ] (Dashboard)
[Battery Inactivity - Tile7 ] (Dashboard)
[BatteryMonitor]
[Control Page ] (Dashboard)
[Device Monitor]
[Garage Door Auto-Lock ] (webCoRE Piston)
[Garage Door Auto-Lock Override ] (webCoRE Piston)
Can you please paste a copy of your lock app to review? I had the same issue and it was refreshing the lock too often, tweaked that (can share my app if you like) and battery life is holding well now. thanks jj
I'm using Lock Code Manager (LCM). I am unaware of a refresh adjustment setting. However, as I mentioned, I've been using LCM for a few years and this issue is more recent.
I wrote this app, the trigger is periodic set at every 5 minutes, or when the door contact changes states. I tried LCM and got better results myself with this app managing the lock. Battery life is about 6 months for 4 AA's. jj
LCM doesn't poll the locks, so it has no effect on battery life.
When LCM is opened it only reads the lockCodes from the Hubitat database for each lock.
Thanks Mike. I kinda thought that was the case. I guess unlinking and relinking the lock is the next step. If that doesn’t help, I’ll have to look for new modules to put in the lock, or just replace the lock. It’s a z-wave lever lock that just started eating batteries.
It's unfortunate that yale no longer produces the zigbee modules, I have 10 yale locks lever and deadbolts, the newer z-wave locks eat batteries unfortunately, I maybe get 6 months out of them whereas the zigbee units that get far more use last a year or more.
You say that the battery life drops to 20% in about 3 weeks, but my experience with almost all battery devices is that the "battery condition" values are unreliable. For example my Weiser lock still shows 100% after 4 months. I only change the battery when I hear the motor slow down. I have tried other drivers which seem to give more accurate battery stats, but I lost other features that were more important. I'm currently using a Schlage driver for example.
So my question is, have you actually left the batteries in the lock to confirm they are really dying sooner than normal, and that you don't simply have a battery reporting issue?
Have you recently changed something in your Z-Wave network? Perhaps removed or replaced a device that was acting as a repeater for your lock.
Some other things to consider outside of Hubitat.......
Is the bolt still sliding easily? If the latch plate is out of alignment, resulting in a resistance to motion, then battery load will be increased. With my Weiser lock I can rotate the knob with light pressure from the tip of my baby finger. This is true when the door is both open and closed.
Did you change your brand of battery? I only use Energizer Lithium batteries, which not only have the longest lifespan, they also maintain their full voltage during winter conditions here in Canada. Are you having any temperature extremes recently?
Are you using alkaline or lithium AA batteries? I only use alkaline because the battery reported level was always really low on lithium batteries because they discharge differently.
I use AA lithium batteries because the voltage per cell (VPC) is higher than the alkaline varieties. Approximately 1.7v vs 1.5v.
This should cause high levels to be reported, and not low as you described. Perhaps the high initial voltage is why my lock reports 100% for such long periods.
Another advantage of lithiunm batteries, is that the output voltage doesn't drop with colder ambient temperature. The voltage drop with alkalines became apparent with motor slowdowns during cold winter days. Even though the electronics are inside the house, the lock is substantially colder than the interior room temperature.
I just looked and most things I read seem to suggest you are right. I may have been merging two incompatible situations in my head..
I do sound for a lot of live events, and the whole lithium vs alkaline thing becomes a problem on our wireless microphone packs. You have to tell it which kind of batteries you use (Alkaline, Lithium, or Nmh) because each battery type discharges differently and it screws with the battery meter. I was always wondering why the lithium batteries which are supposed to last longer usually drop below 50% within 30 minutes while the alkaline batteries took 2-3 hours to get to 50%. Well it turns out that (at least according to Shure Microphones) while the capacity and initial voltage of the lithium batteries IS higher at full charge, under load the voltage actually drops faster on the lithium batteries than the alkaline, causing the battery meter to report inaccurate (lower) levels, unless you properly set the battery type. Turns out I was tossing out perfectly good lithium batteries all the time thinking they were just dying too fast.
Now, where the situation may be different with smart locks is that they only periodically tax the battery, for very short periods of time. The wireless microphones are always pulling a continuous heavy load on the battery (new batteries last about 6 hours til dead). Maybe it's wrong thinking, but it was from this experience that I've avoided using lithium AA batteries in anything designed for standard alkaline AA batteries. My Nest Protect is the only device I have that takes AA batteries and specifically calls for lithium cells on the device itself.
Keep in mind that there are various types of lithium batteries. In this thread we are focusing on the AA size, which are Lithium/Iron Disulfide.
If you want more details regarding the Lithium AA vs Alkaline AA batteries, this PDF from Energizer has plenty. LINK
In particular, the chart in figure #12, shows that Lithium cells can last 4 times longer than Alkaline cells, under the same 1 watt load. Figure #6 shows they last slightly double the time under lighter loads of 250 mW
I think you linked the wrong document. This doesn't have any of the information you referenced.
I specifically mentioned AA batteries on purpose, so that we would all be on the same page.
However, I feel like you misunderstand me. I'm not saying that lithium batteries don't last longer than alkaline batteries. I'm saying I have extensive experience with at least one usage scenario where lithium batteries, while still lasting longer than alkaline counterparts, display a lower than actual value on the devices battery meter leading to uncertainty of remaining capacity.
I thought we were talking about battery meter readings here in this thread. The only reason I ever brought up lithium batteries in the first place was because of the battery meter discrepancy that I know of from something else entirely I run into at work.
Yes, we have drifted a little off topic. The thread is actually about shortened battery life on a lock.
In my original post I suggested that possibly the batteries weren't really dying, but perhaps the device driver was giving erroneous information.
I continued to suggest other methods to increase battery life, including the use of Lithium batteries.
When you described your experience with Lithium battery life, I thought I would share some data which confirms that Lithium cells last considerably longer than Alkaline cells.
Apologies to the OP for getting "slightly" off topic.
Z-wave locks have to use battery power for two things:
To communicate with the hub.
To lock and unlock the door.
To reduce the power needed for communication, place a good Z-wave repeater near the lock such that the lock does not need to waste power. Because they are secure devices, they have to send a lot of data back and forth to the hub. If the lock only has to communicate with the repeater located nearby, it will take a lot less power. The repeater might need high power to communicate with the hub, but because it is plugged into the wall socket, you will never notice it.
To reduce the power needed for mechanical movement, be sure to lubricate the lock periodically, especially the bolt mechanism.
I have a Schlage Z-wave lock. I replace the alkaline batteries about every 6-9 months.
Sorry for my lack of responses for the last few days. I was out of town and just returned a few hours ago. Let me try to catch up a bit,
I used to get 6 months out of the batteries with this same z-Wave lock (before they got to 20-25%). Now it's 3-4 weeks. So apples to apples - i.e., getting to 25% used to take about 6 months. Now it takes only 3-4 weeks.
I use Alkaline batteries. I'm using (4) AA Duracell Coppertops and have for years.
Nothing in my Z-Wave network has changed recently
The distance from the lock to the hub is about 12-15 feet. There are six Z-wave repeaters in the direct path Lock to the hub. Of course, the lock has decided to use a different repeater, but it is using one.
It's a lever lock and the mechanism moves without restriction. That hasn't changed over the life if the lock.
There haven't been any temperature changes at the lock. It's inside the garage on a door leading into the house.
Now that I'm home again, I'll re-link the lock and see what happens.
I have now excluded and then re-included my Z-Wave lock. We'll see if this helps with the battery consumption. I honestly don't have a lot of hope that it will, but we'll find out.
It's early after excluding/including my lock 2 days ago, but the rapid battery decline seems to have stopped. In fact, it was down to 69% (since 21 August) but is now at 73%. I'm hopeful that the excluding/including may have solved the issue but, if true, I'm not sure why.
