Installation
MarathonSeriesFA/FR 19
5.4InstallingtheElectronicsHousing
Thedistancebetweentheelectronicshousingandacomputer(viaRS485cable)canbeupto1200m
(4000 feet). This allows ample distance from the harsh environment where the sensing head is
mountedtoacontrolroomorpulpitwherethecomputerislocated.
For reliableperformanceit is recommendedthat thepower supplybe nomorethan
60m(200feet)away!
Following you can see installation examples shown with two representative cable types.A 4‐wire
cableisusedtowirethe24VDCpowersupplyandoneoutputoftheelectronics
housing.Acoated
12‐wirecableisusedtowireallinputsandoutputsoftheelectronicshousing.
Sometimes in cable bothsets of twisted‐pair wireshave drain wires insidetheir insulation. These
drainwiresmustbeassembledandconnectedtotheterminallabeledSHIELD(bare).Alsoconnectthe
earth
groundtotheSHIELD(bare)terminal.Thefollowingfigureshowshowtoconfigurethedrain
wiresofboth4‐and12‐wirecablesbeforeconnectingtothesensorandRS485/RS232converter.
Figure14:ConfiguringtheSensorCable
Thecompletewiringmusthaveonlyonecommonearthgroundpoint!
Cablescanberuntothe electronicsenclosurethroughconduitorfastenedusingtheacompression
fitting.Onceyourunthecableintotheenclosure,attachthecolor‐codedbarewirestotheterminals.
Usethe followingfigure(or
diagramonundersideoflid)asawiringguide.Notethattheterminal
blocksintheelectronicsenclosurecanbe“popped”outforeasywireconnections.
Twist braided shield and two drain wires from
the two twisted pairs together
ttach to SHIELD
in electronics housing
Earth Ground
Earth Ground
12-wire cable
4-wire cable
To electronics housing
To electronics housing
ttach to SHIELD
in electronics housing
e.g.
to power supply,
to RS232/485 converter,
other in
uts/out
uts
e.g.
to power supply,
0/4 – 20 mA current output
