Specifications

Section-5 Maintenance
November 11, 2013
5‐10
Copyright©2013,HarrisBroadcast
WARNING:Disconnectprimarypowerpriortoservicing. 888‐2628‐300
Note
PS board fuse is 8A 250V fast blow.
STEP 1 TurnoffPAmodulebreaker.
Warning
MODULE MAY BE HOT. ALLOW THE MODULE TO COOL BEFORE REMOVAL.
STEP 2 Allowthemoduletocoolfor30seconds.
STEP 3 UnscrewretainingscrewsandremovePAmodule.
STEP 4 RemovePAmodulecover.
STEP 5 Removefour(4)PSholddownscrews(Phillipsscrews).
STEP 6 RemovesupplywirefromWAGOblock.
STEP 7 Removeboardfromconnectorandcleanupheattransfercompound.
STEP 8 Installanewheattransferpad(411‐0126‐000).
STEP 9 InstallnewPS.
STEP 10 InstallPSholddownscrews.
STEP 11 ReconnectsupplywiretoWAGO.
STEP 12 ReplacePAmodulecover.
STEP 13 ReplacePAmoduleinrack.Tightenmoduleholddownscrews.
STEP 14 TurnonPAmodulebreaker.
STEP 15 PresstransmitterOnbuttontoactivateallmodulesthatareturnedoff.
STEP 16 Endofprocedure.
5.7.2 AC/DCConverter(PS)BoardOutputVoltage
TheoutputofthePSboard(alsoreferredtoastheAC/DCconverterboard)changesdependingontransmitter
modulationtype.TooperateproperlytheoutputofthePSboardmustbeinitiallyadjustedto48V.Thisadjustmentis
madeinthefactoryoneachboardpriortoinstallationintoa
moduleorshipmentasareplacementpart.Theoutput
voltagecanalsobesetinthefieldifamoduletestsystemisavailable.TheoptionalPAmoduletestsystempart
numberis971‐0040‐080.
5.7.2.1 SettingAC/DCConverterVoltage
STEP 1 FollowthePSboardreplacementstepsoutlinedinSection5.7.1onpage5‐9stopping
atstep10.
STEP 2 Placethemoduleinthemoduletestfixture.
STEP 3 RemoveJP1
STEP 4 ActivatethemoduleandsetVoutto48VusingthetrimpotshowninFigure5‐6on
page5‐9.
STEP 5 ReplaceJP1.
STEP 6 Completesteps10‐13inSection5.7.1onpage5‐9. 
STEP 7 Endofprocedure.
TheTCUsendsaVtrimvoltagetothePSboards.TheVtrimvoltagevariesdependingonthetransmittermodulation
selection.ThePSoutputvariesdependingontheVtrimsignalreceivedfromtheTCU.TheVtrimlevelsaregiven
below.
VtrimLevels:
• 5.755V‐‐‐‐44V
• 4.122V‐‐‐46V
• 2.490V‐‐‐‐48V
• 0.875V‐‐‐‐50V