Automist
®
Fixed Wall Head Handbook v1.2.3
Plumis Ltd Copyright © 2017. All Rights Reserved.
Page 19 of 41
S MA RT SC AN
®
A) Preparing the site
Important!
Connecting the system to the mains requires a competent electrician with 17th Edition
Electrical Qualifications. The Automist circuit should be clearly labelled (a sticker is provided for this
purpose). Automist requires an independent 230V a.c. / 50Hz electrical supply, not shared with other
unrelated devices. Components of the fire detection and alarm system may use this circuit, which must
remain powered in the event of a fire. Power to Automist must be provided via an unswitched fused
connection unit (FCU). Automist should be supplied using FP200 cable or better, ideally inside conduit or
protected 50mm deep within a wall, and with no RCD or RCBO protection. RCD or RCBO protection may be
required, however, by applicable electrical installation regulations, in which case the circuit design must be
such that the operation of any other RCD, RCBO or safety device does not affect the operation of Automist.
Typically, on a split-load board, Automist should be connected to the non-protected side of the board.
Where there are no spare ways in the existing consumer unit, or there are no available non-RCD protected
ways in the existing consumer unit, the electrician may wish to use a Henley Block to provide new tails to a
second distribution board (typically a 2- or 4-way unit).
The Automist unit presents a part-inductive load and therefore only t
ype “C”
breakers are suitable. Because
Automist is often used for life safety applications, installers should add a suitable safety margin to the MCB
ratings. The circuit su
pplying a single Automist unit would commonly be protected by a type ‘C10’ or ‘C16’,
for example, or ‘C20’ / ‘C32’ for two Automist units.
This should be on a C-type breaker, on an RCBO or a
RCD protected circuit. The RCD circuit should protect only the Automist system and not be incorporated
with any other circuit in the property. If the consumer unit is located in the protected area it should be
protected by an electrical cover tested to BS476 Part 22 (1987) and EN1364-1 (1999). If the electrical
installation is required to follow BS 8458 DPC, the stipulations of that standard should be adopted; in
particular it requires the use of fuses rather than MCBs and requires a “separately fused connection taken
after the meter and from the supply side of the dome
stic or residential fuse box”.
13 amp fused unswitched connection
unit located close to the Automist pump’s
location
FP 200 fire resistant cable
Separate
circuit
