User manual

4
PUBLIC ACCESS LEVEL 1
4 LOOP DEVICES
This process simply queries the loop for all devices and uses their existing address. No change to the
devices take place and is thus suitable for working on an already commissioned loop.
4.1.1 Retrieve existing devices
Simply and quickly retrieves devices currently known to the loop tester hardware. No querying
of the loop is performed. This does require that hardware have learnt the contents of the loop
since being power up.
4.1.2 Standard search
A standard search polls each address in turn until no device is found. This is fine if you are sure
the loop is complete and all devices are addressable. If you believe otherwise, see sections
4.1.3 and 4.1.4.
4.1.3 Search defined range
Like a standard search, but this will search all addresses in turn up to a define point entered by
the user. This will allow the hardware to detect all connected devices, even if earlier devices are
missing or otherwise un-addressable.
4.1.4 Search range of selected loop
Functionally identical to “Search defined range” except the range is defined according to the
currently selected loop data. See section 7 “Loop databases” for details on loading and using
loop data.
4.1 Pre-addressed
Before devices on the loop can be interfaced with, they need to be addressed and learned by the
loop tester. If the loop being tested is already commissioned, using the existing device addresses is
advisable under normal circumstances. Once the loop devices have been learnt by either of the
processes below, the features for querying the loop devices will be enabled and the view will
automatically switch to the “Devices” pane.