Honeywell Searchline Excel Technical Handbook page 90

MAN0530 Issue 10 - 11/09
2104M0506
APPENDIX A - HANDHELD INTERROGATOR
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The approach to mechanical alignment depends on the type of alignment telescope and mounting
initially used to set up the Excel gas detector, also see Chapter 3.
bayonet-style trident-type telescope assembly
If this type of alignment telescope was used with a Trident-type Excel gas detector, there is no
need to further optimise the alignment using the SHC1 Handheld Interrogator.
When the SIG and TGT bar graphs are displayed on the SHC1 screen, SIG will always be
greater than TGT and installation can proceed to the next stage by pressing Enter and following
step 12.
latch-style telescope assembly
If this type of alignment telescope was used with a Trident-type Excel gas detector, there is no
need to further optimise the alignment using the SHC1 Handheld Interrogator.
If this type of alignment telescope was used with a non-Trident Excel it may be necessary to
further optimise the alignment in the following way in order to achieve best performance.
(a) After the SIG and TGT bar graphs are displayed on the SHC1 screen as previously
described, let the TGT level reach its initial maximum by waiting for approximately
10 seconds.
During this time the tGt level will move up towards the current siG level.
(b) Whilst watching the SIG level closely, make a small mechanical adjustment in either
the horizontal or vertical alignment and note whether the SIG level goes up
or down.
(c) If the SIG level goes up, make another small mechanical adjustment in the same
direction as before.
(d) If the SIG level goes down, change the direction of adjustment.
Maximise the siG level by making small adjustments in only one plane at
a time.
(e) When the SIG level has been maximised in one plane, make small adjustments in
the other plane until SIG has been maximised in this plane.
(f) Repeat steps (b) to (e) until the SIG level has been maximised in both planes.
At this point, siG must be bigger than the initial tGt level and any adjustment either
side of the current alignment must result in a reduction in signal level.
If not, repeat steps (b) to (e) until these requirements have been met.
(g) Lock off the alignment by placing a hex (Allen) key in the pair of grub-screws
which control adjustment in a particular plane and simultaneously rotating them
in opposite directions.
(h) Repeat this for the other pair of grub-screws.
(i) Press Enter and the signal levels are checked.
Provided that the SIG level is greater than the TGT level, the signal check should pass on to
the next stage of installation.
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Searchline Excel