Raytech TraceTek TTDM-128, User Manual

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Location The current location — or electrical center — of the leak (or
cause of a Service alarm). If the SIM status is Normal, the
Location entry is blank.
Sense Cur This current (measured in µA) indicates the condition of the
sensing cable. If a leak is detected in the channel, this rises to
270 µA or more (depending on the type of TTSIM). In a clean,
leak-free sensing circuit, the current should be 5 µA or less. If
the current rises above 20 µA, service is recommended, as it
may indicate the presence of contamination.
Serv Alert >= This setting controls Service Required Alarms. If Sense Cur is
greater than this value, the TTDM signals a Service Alarm.
Sense Res This is the resistance measured between the sensing wires.
For a clean, leak-free sensing circuit, this resistance is in the
MΩ range (more than 1000 kΩ). If liquid is detected, it will
drop to less than 100 kΩ, sometimes to less than 5 kΩ or
even lower. If the value is changing, it may indicate an event
in progress.
Leak Alarm <= This setting controls Leak Alarms. If Sense Res drops below
the threshold level, the TTDM signals a Leak Alarm.
R-G Res,
Y-B Res These are the resistances of the Red-Green and Yellow-Black
loops in the TraceTek sensing circuit. If these values are
significantly different from each other, the TTDM will signal a
Loop Imbalance alarm, indicating damage to a sensing cable
or connector.
SI Version This indicates the software version operating in the SIM
microprocessor.
SI Comm This indicates the success rate (in percent) for
communications between the TTDM-128 and the SIM channel
selected. A value below 90% may indicate a faulty connection
or damaged RS-485 cable.
Add Regions/Relays This entry accesses a submenu that lets the user divide a
length of sensing cable into as many as 10 smaller sections.
Dividing a length of cable into regions can help the user
identify the location of an alarm condition. See Setting Up
Regions, page 26.