European Safety Systems Ltd.
Impress House, Mansell Road, Acton, London W3 7QH
www.e2s.com
Tel: +44 (0)208 743 8880
Document No. D210-00-031-IS
Issue 5
12-09-2022
Sheet 5 of 6
11. AC Wiring
N L
- 2
3 S
to
p
1
23
Fig. 4 AC Terminals
12. DC Wiring
+ -
2
3
S
to
p
1
23
S2
S3
Stop +ve
-v
e
Fig. 6 DC Terminals
12.1 Stop Terminal
The user can remotely activate and deactivate the BExH120D
Hootronic DC sounder by switching a connection from the
“Stop” terminal to the –ve or +ve supply lines, depending on
which switching mode is being used +ve or –ve (see above)
whilst the unit is powered. To achieve the “tail off” sound at
switch off the unit must remain powered.
12.2 Stage Switching Polarity (DC Units Only)
The BExH120D DC sounders have the facility to use ve
or –ve switching to change the tone to the second and third
stages. Negative switching is the default setting. For –ve
switching connect the two headers on the pcb to the left-hand
(marked –ve) and centre pins. For +ve switching connect the
headers to the right hand (ve) and the centre pins.
(Refer to Fig. 7)
+
- 2
3
S
to
p
1
23
S2
S3
Stop +v
e
-ve
Stage Headers Set for –ve Switching
Stage Headers Set for +ve Switching
Fig. 7 Stage Switching Polarity
12.3 Line Monitoring
On BExH120D DC units, dc reverse line monitoring can be
used if required. All DC sounders have a blocking diode fitted
in their supply input lines. An end of line monitoring diode or
an end of line monitoring resistor can be connected across the
+ve and –ve terminals. If an end of line resistor is used it must
have a minimum resistance value of 3k3Ω and a minimum
power rating of 0.5 watts or a minimum resistance value of
500Ω and a minimum power rating of 2 watts.
The resistor must be connected directly across the +ve and -
ve terminals as shown in the following drawing. The resistor
leads should be kept as short as possible.
+ -
2 3
S
top
1
23
S2
S3
Stop +v
e
-v
e
Fig. 8 End of Line Resistor Placement
End of Line Resistor
Stage Headers
AC
Terminals
N
L
C/-
S2
S3
Stop
C/-
Sound Headers
+
C/-
S2
S3
Stop
C/-
Stage
Headers
C/-
