Eaton i-on series Engineering Manual page 41

i-on Range
For each keypad, the Z2 terminals are the for the tamper contacts, and the Z1 terminals
are for the alarm contacts.
Allocating Zones Between Expander and Keypads
It is possible that there may be no zones available to assign to a keypad. This can happen
in two ways:
When the control unit has expanders allocated to all the available zones on the bus.
When the control unit has an expander already allocated to the zones at the top of its
zone numbering range.
For example, if an i-on50EX is fitted with four EXP-W10 expanders, then the expanders
use all the zones available on the control unit, and there will be no zones available to
allocate to any KEY-KPZ01 keypads on the bus (see a) in Figure 9). This applies even if
some of the expanders have unused zones.
As another example, if an i-on30EX has two 10-zone expanders, or an EXP-R30, then
there will be no zones free to allocate to any KEY-KPZ01 that is subsequently fitted to the
system.
Note that the control unit allocates zones in groups of 10. If a KEY-KPZ01 takes up two
zones within a block of 10, then the control unit will not allocate that block of zones to an
expander (see b) in Figure 9).
i-on50EX Zone Numbers:
If an expander happens to take up zones at the top of the numbering range, then the
control unit cannot allocate KEY-KPZ01 zones to zone numbers below the expander (see
c) in Figure 9).
Figure 9. Keypad Zone Numbering Example
The System Bus
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