24
INM4500-2
Mar 2009
6.2.4 MTL4523L - Solenoid Alarm driver
Line powered with line fault detection, IIC
With the MTL4523 interface, an on/off device in a hazardous area can be controlled by a voltage
signal in the safe area. It is suitable for driving loads such as solenoids. Line fault detection (LFD),
which operates irrespective of the output state, is signalled by a safe-area solid-state switch which
energises if a fi eld line is open or short-circuited. Earth fault detection can be provided by connecting
an MTL4220 earth leakage detector to terminal 3.
Note
: Signal plug HAZ1-3 is required for access to the earth leakage detector function.
Hazardous area
Safe area
1 2 3 4 5 6
7 8 9 10 1112
13 14
LFD
+
Solenoid,
alarm or
other IS device
To MTL earth leakage detector
+
Vs
Vs+
2035V dc
Terminal
Function
1
Output
–ve
2
Output
+ve
3
To earth leakage detector*
7
Line fault ve
8
Line fault signal –ve
10
Supply
+ve
11
Supply
–ve
Figure 6.12
LED indicators
for MTL45523L
PWR
STS
LFD
MTL4523L
