I have been using an Enerwave ceiling mounted motion sensor in my system for four months now, and I have been mostly pleased with its performance. I like best that it looks like a smoke detector and blends in. I also like that it runs on a pair of inexpensive AA batteries.
The battery life of my sensors has become increasingly important to me. Each new sensor in the system means new batteries to maintain. Battery life for this sensor is especially important because you need a ladder to get to it. I think eventially you could get to a point where the nuisance of swapping batteries outweighs the benefits gained from automating.
The Enerwave PIR’s user manual claims that it will check the battery level every day and report the battery level by broadcasting a BATTERY_REPORT. Also, when the batteries get down to 1 percent, a value of 0xFF will be sent. I think it would be nice to be able to gather a sensor’s battery data over time and plot it and perhaps be able to predict when the batteries will need replacing. With the Enerwave I’m still running on the original pair of batteries, which is good, but I haven’t received a battery report from the PIR since the day it was first installed.
I have found with a few of my other Z-Wave sensors that they only send a battery report when the battery level drops drastically below the nominal voltage, and for at least one of my sensors that seems to happen when there is barely enough power remaining to send the battery report. Since I hadn’t received a battery report from the Enerwave PIR, I decided to check them manually. The batteries that are currently installed measured 1.62 VDC when they were new, and when I checked them with a Voltmeter today, they were at 1.49 VDC. That’s still close 100 percent of nominal, and it might explain why I hadn’t received a report. While I had the PIR in my hands I woke it up and sent a BATTERY_GET command to it. It reported 100 percent. We’ll have to see if the PIR sends a battery report when the battery level drops a bit more.
Parameters and Settings
The Enerwave PIR only has one configuration parameter: parameter zero (0) is the number of minutes to wait after a motion event before sending a BASIC_SET OFF message. I’ve got mine set to 3 minutes. I also have the wakeup interval set to 14400 seconds. Hopefully these settings will help prolong battery life.
The Enerwave PIR has a “test mode,” which is a green LED that flashes whenever motion is detected. The LED flashes seem to be real-time responses to motion that are independent of the interval at which Z-Wave BASIC_SET commands are sent. The flashing LED may be helpful when searching for a mounting location or when adjusting the sensitivity of the PIR. The term “test mode” suggests to me that there is a way to disable the LED, but I have been unable to identify any parameter setting or switch that does so. I think that in a high-traffic area a constantly flashing LED might result in decreased battery life.
The PIR came with a square of double-stick mounting tape and also a pair of plastic sheetrock anchors, but I didn’t think either of those mounting methods would hold up to the twisting and untwisting of the PIR from its base when changing batteries. I used a stud-finder and ran sheetrock screws through the PIR’s base all the way into a truss.
If I had a complaint, it would be that the Enerwave PIR is too sensitive. Sensitivity can supposedly be set using a pair of DIP switches on the back of the unit:
Even with the switches set to 25 percent sensitivity, I still cannot drag a bucket of lukewarm water (my pet simulator) past the PIR slowly enough that it won’t set it off. Fortunately I have no pets, and even with it set at 100 percent sensitivity, I haven’t had any false alarms during the four months the PIR has been in service. The PIR is so sensitive however, that the motion alarm will trip when I come home from work and open the front door. That’s 25 feet away and at the extreme edge of the PIR’s claimed sensing perimeter. I’ve been having to use a minimote to disarm the alarm system before I enter the house. I should probably program a delay into the system to give me a chance to get to the indoor keypad before the alarm goes off.
Network inclusion is straightforward and is performed by clicking the little black button on the back of the unit. Tapping this button four of five times wakes the unit up. Tapping the button repeatedly, as I have become accustomed to doing with a couple of other brands of sensors, works to keep the unit awake during network optimization, “healing,” re-discovery, and other such lengthy handshaking procedures.
The Enerwave Ceiling Mounted Z-Wave Motion Sensor seems to have good battery life, and it’s not as conspicuous as most of the wall-mounted PIRs that are available. The user manual claims that battery status is reported on a daily basis, but I have found that isn’t actually the case. This sensor, like a few other battery-powered Z-Wave sensors in my system is somewhat lacking in its ability to accurately detect and report battery level. The “test mode” flashing LED was helpful when selecting a mounting location, but even with sensitivity set to the lowest level, the LED would still flash in response to the slightest motion of a pet-sized heat source. On the other hand, the sensing perimeter and distance seemed to be even greater than what is claimed in the user’s manual. Enerwave was hinting at the 2015 CES that they had a multi-sensor version of their ceiling mount PIR in the works, but I haven’t heard any news about that lately. In the meantime, I’m happy with this one.