Faraday MPC-2000 Smoke Detector Replacement

Discussion of all things related to fire alarms, including alarm systems, fire alarm collections, sirens, sprinklers, fire drills, evacuations, actual fires, building architecture, other kinds of safety drills like tornado and earthquake drills and such, etc.
Post Reply
Registered User
Registered User
Posts: 1
Joined: Tue Nov 06, 2018 6:34 pm

Wed Nov 07, 2018 12:10 pm

Hi everyone, I have an old Faraday Mpc-2000 that had a bad smoke detector that we recently replaced. When we went to order a new one we were told that the original that was installed on the system (System Sensor 2251) was no longer made and had been only supplied to panel manufacturers at the time. The "like for like" replacement, that plugged right into the existing base was a Secutron 2251B. This detector functions correctly but has caused a trouble on the panel reading "MAINT TRBL" and we can't get it to clear. I usually see Maint. troubles on a dirty detector/out of threshold and not sure if there is someway we need to hook up to the panel or go into programming to get it to reset. Is anyone familiar with replacing detectors on the Faraday MPC-2000? Could it be a firmware issue with the new detector?

The smoke detectors are the addressable rotary decade switch style.
One of the technicians says that there was a TST trouble on the nuisance detector that was replaced.
Also I've noticed that the base contacts are off by a few degrees from the new detectors but power, alarm, latching and reset have tested correctly.

Any and help ideas or help would be appreciated. Thanks,

User avatar
Fire Alarm Technician
Fire Alarm Technician
Posts: 167
Joined: Sat Apr 21, 2007 12:02 am
Location: New Mexico

Fri Nov 16, 2018 5:58 pm

Let me say I haven't dealt with this specific panel before, but I do have some general thoughts from working with many systems including those that use these System Sensor addressable detectors.

First to check is if the new detector is actually dirty. There are four tabs on the back that allow you to disassemble the detection chamber. You can then spray it out well with compressed air. It may take up to a day or so for a dirty trouble to clear once you reinstall the device if that was the issue.

Detector dirty thresholds can be a funny thing on many panels. Clean or replacement detectors often won't clear the trouble right away, but it should clear within a day or so. In rare cases the panel gets into some weird state and the trouble will persist longer than a few days. There may be some sort of manual maintenance reset on this panel but this sort of thing is not necessary on most panels.

You can try power cycling the panel. First disconnect one of the battery terminals, then switch the breaker off and back on after a 10 seconds or so. Be aware that if setting the clock requires a password, though, you may not be able to set it back to the correct time.

I am not aware of any addressable protocol differences between the 2251 and 2251B. I believe the 2251B is intentionally designed as a backward compatible drop-in for systems like this one that use System Sensor's CLIP protocol. It may be the case that the Secutron version you have is slightly different though.

If power cycling doesn't help, the replacement detector may be faulty, or the panel may dislike that the Secutron branded detector is different from a generic System Sensor 2251B. In either case you may have to find a supplier for a System Sensor 2251B. I know we have a few on our shelf, but you can almost certainly get one from your local Gamewell-FCI or Notifier distributor.
Post Reply