Read this with interest,I have a situation where I have a part install (previous sparky)and have been asked to finish it off.Taking some advice from a Fire systems supplier representative he said that i could either join using a crimped connection or a ceramic connection.He said no to the wago route.Must be in a galz box though.He also suggested that the use of 4 core FP200 was not a good idea as it seems I have a sounder radial circuit and a zone radial circuit sharing the same cable.He suggested 2 core cable FP200 for all zones,seperate cable for sounders.Shame really as it means installing another high long run of cable,but no compromises.
Reference crimp connectors - advice please would you use the decent aluminium ones and then heat shrink over or those butt pre insulated ones which i am not a fan off.Although dealing with 1.5 wire what else is there ?
Thanks,hopefully the thread is still active !!!!
Hi Roger
Not sure who your rep was - Wagos ARE considered permanent, if used in a fire rated galv junction box. They are new, and not specifically mentioned in the standards, but the key point is that they exceed the connection method offered by connector block, and match the termination provided by crimping, as they are considered permanent, albeit they can be released with the use of tools.
I'd be happy to challenge your rep on this point, as Wago connectors ARE acceptable per BS7671, which is the standard we also use for wiring in fire alarms - it is called in by BS5839. They are, as it happens, also fire rated when installed in a fire retardant enclosure.
Traditionally, yes, we use crimps, or ceramic connectors - Wagos are just faster and work equally well for FP200 or Pyro.
We don't recommend use of 4 core cable for the simple reason that sounders and detection need to be kept separate - and that is the very same reason I often speak out against so called "twin wire" systems" in principle. The whole point of a fire system is maintaining integrity as far as practical.
In PRACTICE, however, it is sometimes desirable to use one run of four core FP in place of two runs of 2 core - and providing it doesn't also carry an End of Line device on the four core section, then any fault monitoring should not be affected. It comes down to a matter of judgment as to how using the 4 core will affect the overall integrity of the installation. The preference is for separate two core runs for each detection circuit, with sounder circuits run segregated - i.e. along a different route as far as possible, but practice, as we all know, is often different.
Regards crimps - the object is simply to make a joint with the lowest possible resistance - high quality aluminium will give that, as will pre-insulated ones, done properly - again, it is a matter of choice - we use both, though my preference, like you, is uninsulated with rated heat shrink. I would still be inclined to re-investigate the Wago route however, as I can find no reason not to use them within a Galv box.
Yes, if you can see a thread, it is still active
