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Zone Expander Cards
Up to sixteen zone expander cards may be fitted to the GardTec
872
. If required one of
these expander cards may be plugged directly onto the the main PCB, the other
expander cards then being wired to the plug-on card as shown in Fig. 30.
Four cores
are required for interconnection of the zone expanders. If Output Expanders are
to be used on the same leg as zone expanders an extra core will be required.
The expanders are wired in two groups EXP1 to EXP8 use SAD1 and EXP9 to EXP16
use SAD2
Fig. 30a GardTec
872
Expander Card Wiring 'Daisy Chain' Format for EXP1 to EXP8
Group 1
872
872
To Other
Expander1 (Plugged on)
Expander2
Expander3
Expanders
12V
12V
12V
0V
0V
0V
SAD1
SAD 1
SAD1
SCLK
SCLK
SCLK
If you intend to use Expanders 9 to 16 or any Output expanders also wire SAD2
terminals.
Fig. 30b GardTec
872
Expander Card Wiring 'Daisy Chain' Format for EXP9 to EXP16
From Group1
872
872
To Other
Expander
Expander9
Expander10
Expanders
12V
12V
12V
0V
0V
0V
SAD 2
SAD 1
SAD 1
SCLK
SCLK
SCLK
The expander cards may also be wired back to the onboard expander card in 'Star'
format (each expander card wired back individually).
Alternatively all the zone expander cards may be wired to the main PCB via an
optional zone expander cable Part No. 01-094.. When using the zone expander cable
the following colours should be used (see Figs 31a, 31b).
If Output expanders or
Group 2
Expanders are used
SAD2
terminals should be used
on the first group. If the expanders are remote from the main PCB a second expander
cable will be required to plug onto PCB
EXP2
socket. The
SAD2
connection on this
second cable is the yellow core.
GardTec
872
Wiring Connections
872.qxd 05/11/2003 15:01 Page 39
