Spur (Chain) Configuration - Siemens SPC4000 Installation & Configuration Manual

7.1.1

Spur (Chain) Configuration

Siemens Building Technologies
Fire Safety & Security Products
The Spur, or open loop, cabling method offers a high level of fault tolerance and
may be more convenient on certain installations. In the case of a cable fault or
break, all Expanders and detectors up to the fault continues to be supervised.
On the SPC, only a single port supports a group of Expanders. The last Expander
in an open loop configuration is not wired back to the controller and can be
identified by the fast LED flashing light (one flash every 0.2 seconds approx) when
in Full Engineer programming.
Numbering for the Expanders commences at the Expander nearest to the
Controller and ends with the Expander connected farthest from the SPC Controller.
Eg. if six Expanders are connected in an open loop configuration, then the nearest
Expander on the X-BUS connection is Expander 1, the second nearest Expander is
2, etc. ending with the Expander wired farthest from the SPC Controller, which is
Expander 6.
Within the open loop wiring configuration all Expanders/Keypads are fitted with a
jumper, as default, allowing termination on the device.
1 Controller
2 Expander Three
3 Expander Two
4 Expander One
Fig. 5 Spur (Chain) Configuration
Wiring the System
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09.2008