System Sensor COSMOD4W

i4 Interface Module

Average rating:

(based upon one review)

The System Sensor COSMOD4W is the required interface module for use with the COSMO-4W Smoke and CO Detector. Up to 12 of the COSMO-4W devices can be connected with the COSMOD4W. The module features helpful LED status lights. Purchase the COSMOD4W i4 Interface Module from Alarm Grid.
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The System Sensor COSMOD4W i4 Interface Module is used for connecting up to 12 COSMO-4W Combination Smoke and CO Detector Sensors and using them on just two hardwired zones. The module is required to use the COSMO-4W devices properly. All COSMO-4W Sensors connect directly with the module.

In addition to the COSMOD4W i4 Interface Module, the COSMO-4W Sensors also require the use of a power relay and end-of-line power supervision. The two zones used with the sensors are for fire detection and CO detection respectively. All COSMO-4W Sensors used in the network will enroll on these zones. The module also provides helpful LED lights that display the current status of the COSMO-4W Sensors.

Brand: System Sensor

Very Difficult to Use
Submitted on 01/22/2020 Alarm Grid

The System Sensor COSMOD4W is the required i4 interface module for use with System Sensor COSMO-4W Hardwired Combination Smoke and CO Detectors. The COSMO-4W is a rather unique 4-wire life-safety sensor option that isn't set up like a traditional 4-wire device for a security system. You need to use this COSMOD4W module with a COSMO-4W device. But that isn't enough, as you must also set up a reset relay and a CO trigger relay for the set up to work properly. And to top it all off, the System Sensor COSMOD4W is very difficult and tedious to set up. As such, we do not recommend using it. Most users will find that using traditional 2-wire smoke detectors on a designated reset zone and 4-wire carbon monoxide sensors at a regular hardwired zone is a preferable option. Simply put, we do not like the System Sensor COSMOD4W, and we only rate it at 2 Stars.

There are some positive aspects about the System Sensor COSMOD4W. The COSMO devices are the only hardwired combination smoke and CO sensors that we know about. The fact that these devices combine both a smoke detector and a CO detector into one hardwired sensor is a pretty novel concept that does deserve some praise. And we also like the fact that this interface module offers one-go-all-go functionality for all of the connected COSMO Sensors. This can be important for ensuring that all building occupants are alerted to the fire or carbon monoxide alarm.

But we must really stress that the downsides to the System Sensor COSMOD4W are really serious. DIY users will find that the module is extremely difficult to set up and really not worth the trouble. And the fact that a reset relay and a CO trigger relay must both be added only compounds this issue. Whenever a user asks about the System Sensor COSMOD4W, we will instead recommend that they use 2-wire smoke detectors and 4-wire CO detectors on separate zones, because that set up is significantly easier to achieve. Overall, we cannot recommend this device due to its serious downsides. It only gets a 2 Star rating from Alarm Grid.

Good: Combination Wired Smoke & CO Sensor, One-Go-All-Go

Bad: Difficult to Install, Needs Reset Relay & CO Trigger Relay

Bottom Line: 2 Stars

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