ID2000 Series Installation & Commissioning Manual
ID2000 System Design Guide
Use AT LEAST TWO
sounder circuits to
guard against failure.
Starting the Loop
The following rules give a simplified way to ensure that a
system design will operate correctly. This guide uses worst
case figures and simplifies many of the calculations to
ensure that a design which adheres to this guide will work
when installed correctly. The Loop and Battery Calculator
Support Tool software package will give more accurate
results. As this guide uses worst case figures it is possible
a working system may appear unsuitable if checked using
this guide even though it is perfectly adequate.
It is recommended that at least two separate sounder circuits
are used, to ensure that some sounders do sound if one
circuit is lost.
To ensure loop isolators will close at power up no more
than 25 Start Units (SU's) may be connected between
standard isolators, or 20 Start Units between FET isolators.
Each device has an SU count:
Beam Detector LPB700
Loop Sounders (see next page)
The loop length can be significantly affected by the
distibution of the load around the loop. The calculations for
this are complex and not considered in this guide. The worst
case loop length is given for a completely unbalanced
system. In most cases the actual achievable loop length
can be significantly longer than this (up to 800% longer
depending on the installation) but cannot be guaranteed
using only this simplified guide. If longer lengths are required
then the Loop Length and Battery Calculator Support Tool
should be used to check suitability.
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997-433-000-5, Issue 5