Archive for April, 2015|Monthly archive page

Silencing the DOTL

Monday, April 6th, 2015

Door Open To Long (DOTL) sounders are used at a door to warn when the door has been left open longer than a pre-set time. They are also sometimes used in large retail stores with secure fire exits to alert staff if a customer opens the door.

The problem is that in the event of a fire alarm the DOTL alarms will automatically sound when the fire trip drops the lock power or the doors are left open. This can be confusing for evacuees and they may hesitate to use that exit. In a false alarm the DOTL sounders are downright annoying and inconvenient.

The solution is to fire trip the DOTL sounders. When designing your power distribution you should wire the DOTL sounder power from a fire tripped output of the PP8FR. They will continue to work as normal until the FIP is activated. Using this method will not affect alarms being generated in the in security software.

PP8FR DOTL Connection


This requirement is now being built into many designs and specifications.

Product end of life notice: PP4F

Saturday, April 4th, 2015

The PP4F will no longer be stocked by our wholesalers.

The PP4F was a four way direct expansion module for the PP8FR. With the addition of the much more cost effective and smaller PP10HD to the Jack Fuse range we see little reason to continue the PP4F.

Data and install notes will still be available for some time on the main Jack Fuse website and will be moved to a permanent legacy data page at a later date.