Capital Business Park
Cardiff, CF3 2PZ
groupscs.co.uk
Smoke Control System
EV-HMI7B User Manual
SW Version: 1C
SCS-OM-03-V1_06-2022
Page | 7 of 14
EV-HE077 Override Switches
Optional switches connected to the EV-301 interface panels provide local override control and maintenance
operation of the smoke ventilator with visual and audible indication. It has a secured hinged door with a
common key lock to prevent tampering and a frangible break-glass element for emergency use.
Red Button:
OPEN (BOOST) -
Override open command and firefighting boost button.
Black Button:
CLOSE (RESET) -
Override close command and reset button.
Override Switch Indication:
Colour
Status
Description
Red
Alarm
Emergency alarm condition active
Green
Healthy
Interface panel power supply healthy
Yellow
Fault
Fault condition present
A buzzer pulses when the system is in alarm, or a fault condition is present.
3.2.1.
Manual activation
Whilst the system is in standby or normal mode, emergency smoke clearance can be initiated by pressing the
red
OPEN
button.
3.2.2.
Override Close
When in alarm press the black
CLOSE
button momentary between 1 to 3 seconds for an override close
command.
3.2.3.
Override Open
When in alarm press the
OPEN
button momentary between 1 to 3 seconds for an override open command.
All other zone shaft vents need to be closed before an override open command is accepted.
3.2.4.
Reset
Press and hold the
CLOSE
button for more than 5 seconds to perform a system reset.
3.2.5.
Silence Fault
The switch buzzer sounds on a fault and can be silenced if no emergency condition is present.
To mute the buzzer momentary press the override switch CLOSE/RESET for less than a 1 second.
