Edwards LaserSense HSSD-2

Chapter 2: Installation and assembly
LaserSense HSSD-2 Aspirating Smoke Detector Installers Handbook 21
Removing and replacing the front cover
To remove the front cover, unlock it using the key provided (turn counter-
clockwise). The bottom of the front cover may then be lifted away from the
detector chassis until the top of the cover disengages from the retaining rails at
the top of the chassis. The cover may then be removed.
If greater internal access is required, e.g., for software upgrades, it may be
necessary to remove the front panel display. To do this, use an anti-static wrist
strap to prevent possible static damage to the unit’s electronics and proceed as
follows.
To remove the display:
1. Power down the unit.
2. Unfasten the four counter-sunk crosshead screws holding the display to the
display mounting brackets.
3. Lift the display away from the main board.
Note: It is not necessary to remove the remaining four screws.
If the display needs to be completely removed, unplug the display ribbon
connectors from the detector or command module main board, taking note of the
position of the connectors which are as follows:
• For the standard detector, a single ribbon cable connected to the detector’s
front panel display connector.
• For the command module Detector, a twin ribbon cable, one ribbon
connected to the detector’s front panel” display connector and marked
“DISPLAY DET,” and one connected to the command module board’s
Commander Display connector and marked “COMMAND CM.”
• For the Stand-Alone command module, a twin ribbon cable, one ribbon
connected to the detector display connector and marked “COMMAND DET,”
and one connected to the Commander Display connector and marked
“COMMAND CM.”
When the display needs to be completely removed, disengage the ribbon
connectors from the main detector or command module board and NOT from the
display board.
Refitting of the display is the reverse of the above. Ensure that the connectors
are refitted as described above. To refit the front cover, hook the recessed lip at
the top of the front cover behind the two retaining guard rails at the top of the
chassis as shown in Figure 13 on page 22.