17
8013741/16LH/V1-7/2020-04| SICK
O P E R A T I N G I N S T R U C T I O N S | MCS300P Ex
Subject to change without notice
PRODUCT DESCRIPTION
2
Ex control unit FS840 (for MCS300P Ex category 3G)
Ex control unit FS840 will trigger an alarm signal when the pressurized enclosure is not in
the correct operating state (malfunction).
Ex control unit F840S (for MCS300P Ex category 2G)
Ex control unit FS850S switches the main power supply of the MCS300P Ex and the Ex
interface relays on and off.
●
ON: After the pre-purge phase has ended.
●
OFF: When the pressurized enclosure is not in the correct operating state (malfunction).
The Ex power relay controls the main power supply of the MCS300P Ex (
for MCS300P Ex category 2G”, page 16
).
Ex power relay SR853 (for MCS300P Ex category 2G)
Ex power relay SR853 (optional for MCS300P Ex category 3G) serves to separate the non-
intrinsically safe main power supply of the MCS300P Ex and the Ex interface relay.
Ex interface relay SR852 (for MCS300P Ex category 2G)
Ex interface relay SR852 serves to separate the non-intrinsically safe signal lines (data
lines).
2.3.3
Internal temperature monitor
The MCS300P Ex has 2 monitor devices for both internal temperature controllers.
Depending on the temperature class, there is a maximum temperature of (T
max
) at which
the temperature monitor triggers and switches the heater off.
Tolerances can cause the temperature monitoring to trigger at a temperature slightly lower
than T
max
.
Observe the maximum nominal temperature:
2.3.4
Combustible sample gas
When using an appropriate SICK Ex cell, the MCS300P Ex is capable of measuring
combustible and occasionally ignitable gases (corresponding to Zone 1).
The number of required interface relays depends on the individual application.
▸
Observe the System Documentation provided.
Temperature class
T
max
Maximum nominal
temperature
T4
135 °C (275 °F)
123 °C (253 °F)
T3
150 °C (302 °F)
137 °C (278 °F)
